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2024 Rules
Midwest Street Division (MSD)
No Mods Walls Speakers Power Max Voltage Music/Tone Time Average/Peak
MSD 1
B-Pillar Forward Yes 1-12, 2-10’s, or 3-8’s Unlimited 15.5 Music 30 seconds Peak
MSD 2
B-Pillar Forward Yes 1-15, 2-12’s, 3-10’s, or 4-8’s Unlimited 15.5 Music 30 seconds
Peak
MSD 3
B-Pillar Forward Yes 1-24, 1-21, 1-18, 2-15’s, 4-12’s, 6-10’s, or 9-8’s
Unlimited 15.5 Music 30 seconds
Peak
MSD 4
B-Pillar Forward Yes Unlimited Unlimited 15.5 Music 30 seconds
Peak
Basic Division
No Mods Walls Speakers Power Max Voltage Music/Tone Time Average/Peak
Basic 1
Passenger Compartment No 1-15, 2-12’s, 3-10’s, 4-8’s, or 7-6.5’s
1,000 watts 15.5 Any 30 seconds
Peak
Basic 2
Passenger Compartment No 1-24, 1-21, 1-18, 2-15’s, 4-12’s, 6-10’s, 9-8’s,
or 14-6.5’s 2,000 watts 15.5 Any 30 seconds
Peak
Basic 3
Passenger Compartment No Unlimited 4,000 watts 15.5 Any 30 seconds
Peak
Basic 4
Passenger Compartment No Unlimited 8,000 watts 15.5 Any 30 seconds
Peak
Basic Trunk
Passenger Compartment No Unlimited 4,000 watts 15.5 Any 30 seconds
Peak
Advanced Division
No Mods Walls Speakers Power Max Voltage Music/Tone Time Average/Peak
Advanced Trunk B-Pillar Forward No Unlimited Unlimited 18.0 Any
30 seconds
Peak
Advanced No-Wall
Above window line / B-Pillar Forward No Unlimited Unlimited 18.0 Any
30 seconds
Peak
Advanced 1
B-Pillar Forward Yes 1-24, 2-21’s, 2-18’s, 4-15’s, 6-12’s, 9-10’s, 14-8’s, 21-6.5’s
4,000 watts 18.0 Any 30 seconds
Peak
Advanced 2
B-Pillar Forward Yes 2-24’s, 3-21’s, 4-18’s, 6-15’s, 9-12’s, 13-10’s, 21-8’s, 31-6.5’s
8,000 watts 18.0 Any 30 seconds
Peak
Advanced 3
B-Pillar Forward Yes Unlimited Unlimited 18.0 Any 30 seconds
Peak
Xtreme Division
No Mods Walls Speakers Power Max Voltage Music/Tone Time Average/Peak
Xtreme 1
Passenger Compartment No 1-15, 2-12’s, 3-10’s, 4-8’s, or 7-6.5’s
Unlimited 15.5 Music 30 seconds
Average
Xtreme 2
Passenger Compartment No Unlimited Unlimited 15.5 Music 30 seconds
Average
Xtreme 3
B-Pillar Forward Yes 1-24, 2-21’s, 2-18’s, 4-15’s, 6-12’s, 9-10’s, 14-8’s, 21-6.5’s
Unlimited 18.0 Music 30 seconds
Average
Xtreme 4
B-Pillar Forward Yes Unlimited Unlimited 18.0 Music 30 seconds
Average
Kaos Division
No Mods Walls Speakers Power Max Voltage Music/Tone Time Average/Peak
Kaos 1
Passenger Compartment No 1-15, 2-12’s, 3-10’s, 4-8’s, or 7-6.5’s
Unlimited 15.5 Music 90 seconds
Average
Kaos 2
Passenger Compartment No Unlimited Unlimited 15.5 Music 90 seconds
Average
Kaos 3
B-Pillar Forward Yes 1-24, 2-21’s, 2-18’s, 4-15’s, 6-12’s, 9-10’s, 14-8’s, 21-6.5’s
Unlimited 18.0 Music 90 seconds
Average
Kaos 4
B-Pillar Forward Yes Unlimited Unlimited 18.0 Music 90 seconds
Average
Mayhem Division
Mods Walls Speakers Power Max Voltage Music/Tone Time Average/Peak
Mayhem Max
Required Yes Unlimited Unlimited 18.0 Any 30 seconds Peak
Mayhem Hertz
Required Yes Unlimited Unlimited 18.0 Music 30 seconds
Average
2024 Competition Season
Section 1 – General Rules
1-1 Competitors may use any audio format they choose to achieve their highest Sound Pressure Level (SPL). This includes test tones, sine sweeps, MP3’s, commercially available CD’s, burned CD’s, and thumb drives. Competitors in Basic, Advanced, and Mayhem Max may choose to “burp” their system for a few seconds or play all out for the full 30 seconds. Competitors in Mayhem Hertz, Kaos and/or Xtreme classes must play music.
1-2 When music is required to be played, no test tones, sine sweeps, or music with a single continuous tone will be allowed. The song must have a visible variation in frequency or amplitude on the TermLab metering screen. In some cases, a 2/3 vote by judges will be required to determine legitimate music.
1-3 Music played through mids/highs must be audible outside the vehicle during the run. (Intent: audible music must be coming from within or outside the vehicle).
1-4 Competitors are required to not use any audible music with foul language, profanity, or lewd & suggestive lyrics at any time or place during the event. If an issue arises, a competitor may be required to play a different song, not compete, or may be removed from the event.
1-5 There is an 80 Hz limit in all peak SPL classes.
1-6 The competitor may have their vehicle running during their run as long as the following requirements are met:
• The emergency brake must be set and function correctly
• The wheels are chocked or blocked
• A maximum approximate engine idle speed is not to exceed 2000 RPM. Over-revving is not permitted. Competitors who over-rev their engines (based upon judges discretion during qualifying) may be asked to re-qualify. Over-revving during elimination rounds may result in a loss.
• The use of accelerator/idle adjustments is permitted. Accelerator props must not exceed 1”x1” square.
• Competitors that choose to idle up their vehicle MUST have a tachometer installed.
• Vehicle does not violate emissions rule (see 4-10).
1-7 Only the registered competitor(s) may operate the sound system. The operator may choose to stand outside and/or sit inside the vehicle during competition. Anyone choosing to sit in the vehicle during the run must be of legal age to operate a motor vehicle. If you are under the legal age to operate a motor vehicle, your legal guardian or designee may sit in the vehicle while you operate the stereo from outside the vehicle. Those sitting in the vehicle must sit on the driver’s side. Competitors sitting in the vehicle may not sit in such a way as to manipulate their SPL score. Typically, this is the center cross line of the vehicle.
1-7a If using an external radio box, the box cannot cross into the passenger seat area any time during the run and must remain in the driver seat area or outside the vehicle. This is up to the discretion of the head judge.
1-8 Competitors may choose to open their doors, windows, and other openings of the vehicle during the metering process, however, doors and other openings are not to be slammed during this time. Exception: 9-24
1-9 Once the SPL metering process begins, competitors will have a specified time limit to achieve their highest SPL. Any audio adjustments can be made to the sound system before, during, and/or after that time. Additional runs may be allowed if time permits.
1-10 When safety is an issue, it shall be up to the judge’s discretion to append or modify a rule on a case-by-case basis.
Section 2 – Judging Format
2-1 The judging of the event will be easy – provided competitors are aware of the rules and prepare their vehicle accordingly. We encourage all competitors to fully read these rules to completely understand their intent.
2-2 When qualifying for the event, the competitor will open their vehicle for the official to place the proper measurement equipment inside their vehicle. This includes:
• SPL Sensor to measure the Sound Pressure Level
• Termlab Probe Meter will be installed to measure wattage (power class verification ONLY)
• Judge may verify installation of equipment
2-3 The judging equipment may not be touched by the competitor after it is placed in the vehicle.
2-4 After the run, the judge will determine: (1) if competing in a music class if music being played is allowed, (2) Termlab verification of power.
2-5 If there is equipment failure after the first qualifying attempt, competitors will have a predetermined time to fix or replace damaged equipment before they run again.
2-6 The competitor, if they choose, can qualify a second time to re-establish their class or to improve their score (additional attempts may vary from event to event, and may be subject to a rerun fee.). If the competitor’s wattage class does not change – then that competitor will automatically be in that designated class. If the competitor’s score improves – then the higher of the two scores will be kept, unless the result is a class change. Then that competitor can choose to have the newly established score/wattage nullified. The time in which a competitor may take their rerun will be at the discretion of the head judge.
2-7 Once all competitors have qualified for their class, the top 4 competitors (sometimes 8 depending on size of event) in each class will compete for 1st, 2nd, and 3rd place. First place qualifier goes against eighth place qualifier and second place qualifier goes against seventh place qualifier, etc. The winners will advance to the next round (semi finals) where another bracket will take place. The person with the higher incoming score (quarter finals win) that loses in semifinals will get 3rd place. We do not track or count losing scores. The winners of the semi-final rounds will advance to the final round to compete for 1st place.
2-8 Eliminations are single elimination format. Competitors will not be allowed to rerun during this time. Situations may arise where a rerun might be allowed due to failure in metering equipment, or other unforeseen situations that the competitor or team are not responsible for. This is at the discretion of the head judge.
2-9 If there is a judging equipment failure in a competitor’s vehicle, that vehicle/competitor may need to rerun in order to get a legit score. If the failure happens after a score is posted, then the judge may or may not require the competitor to run again. If a rerun is required, the competitor in the opposite lane may choose to keep their original score and not run again OR delete their score and rerun to obtain a new score.
2-10 When, in the case of a broken or cracked windshield – the sensor may be attached to the window via any means possible in order to hold in place to ensure a safe and accurate reading.
2-11 In the event there is a tie in an elimination round, both competitors will re-run.
2-12 If during an elimination round both competitors exceed their class’s power limit, then both competitors will rerun until one competitor has an official score.
2-13 If there is a dispute regarding the competitors own score or power, it must be made immediately aware to the judging staff after the run. Once the competitor leaves the judging lanes, he or she acknowledges their run was accurate and complete. If the judging staff deliberates and makes a decision contrary to the outcome of the run, then both competitors will be notified of the outcome.
2-14 Competitors & teams in the lanes must remain with the vehicle being judged during the judging process (before, during, & after) until after scores & wattages are verified by judges. During set up and tear down, competitors, teams, and family members are asked to step away until all equipment is removed from the vehicle. If a judge feels that a competitor or team has violated this rule, then disciplinary actions may take place. One or both vehicles rerun, scores dismissed, person/competitor removed from judging lanes.
2-15 To compete in a clamped power class – the equipment must meet the requirements of rule 8-3.
Section 3 – Vehicle Interior Requirements
3-1 No obstructions or modifications can affect the placement of the sensor and/or manipulate the SPL reading. This includes any items (seats or other obstacles) within 12” of any part of the sensor. In case of dash pods, sensor placement will be 12” to the left of the pod.
3-2 Standard sensor position will be at the “legal” position – 12 inches from the passenger A pillar (horizontally) and 4 inches off of the dash (vertically) unless otherwise noted by class division.
3-3 All window and door/hatch openings need to function normally unless otherwise noted by class division. They must be able to open and shut and also roll up and down. Silicone used on windows (to prevent water leaks) needs to be proven that the modification doesn’t affect the SPL score. Sun/Moon roofs/vents may not be removed – but they do not need to function, and will be treated as if they don’t exist. Exceptions to these rules are listed in Section 6. No taping or sealing of window openings.
3-4 The vehicle must have front seats. If the OEM seats came with headrests and/or armrests, then those items must remain in place. Seats, seat brackets, or other seating mounts may not be modified unless noted otherwise. Front seats may be folded and adjusted for competition, but may not be removed from the vehicle.
3-5 Rear seats, if intended, may be folded during competition. Rear head rests may be removed if this is part of the normal operation of folding the seats and at the competitor’s discretion, removed from the vehicle. Modifications allowing the rear seat to partially stay open must be made in the cargo area and must not prevent the normal opening and closing of the rear seat.
3-6 Rear seat backs in trunk vehicles may be folded. Solid non/folding trunk vehicles may unbolt / latch their rear seat back portion only. The unbolted seat back must remain in the vehicle on top of the bottom seat as if folded.
3-7 Second row seating in vans and SUV’s must remain in the OEM location. If designed to do so, they can be folded but not removed. Third row seating may be folded or removed from the vehicle.
3-8 If the vehicle is an extended-cab or king-cab pickup truck, you do not need to be able to fold the rear (side or forward facing) seats as normal operation. Seats may not be removed from the vehicle, but may be folded up during competition.
3-9 Interior panels/carpet, including those in the trunk, hatch, or cargo area, must remain in OEM position unless custom trim panels are used.
Notice – The spare tire, cover, and tools may be removed.
3-10 Interior mods are limited by the class the competitor is in.
Notice – Examples of interior mods (but not limited to):
• Replacing/Modifying the OEM windshield/side windows
• Replacing/Modifying the OEM dash and components
• Replacing/Modifying the OEM seats
• Replacing/Modifying the OEM door panels
• Replacing/Modifying the OEM headliner
• Replacing/Modifying the OEM floor
• Replacing/Modifying the OEM carpeting
• Replacing/Modifying any OEM interior panels
Notice – Seat Limitations
• Seats not allowed: Go-Cart seats, arcade game seats, dune buggy seats, etc. They are not considered OEM equivalent
• Aftermarket seats, or those from another vehicle are allowed – provided they approximate both form, size, and function of the original OEM seat
• Seats must remain in the forward facing position
• Seats must be fully bolted and secured in their original OEM location.
• Replacement seats must be bolted in the rear most OEM bolt hole location
• Custom seat brackets are at the sole discretion of the head judge
• Modifying seats in order to fold or slide forward past their original OEM specification is prohibited.
• If the vehicle came with floor pedestals (to raise the seat), then those are required to stay in place when replacing seats
3-11 Door panels must not be glued, overly screwed, or siliconed on. In other words, they can not be sealed to the door and must be easily removed in similar mode/fashion and ease of OEM panels if required.
3-12 Custom interior panels must be covered or painted. Modifications are allowed – provided they accommodate accessories, sound, video system, or for cosmetic reasons; as long as they are constructed and utilized from the original OEM panel. Custom cargo/hatch trim panels must be covered or painted. Modifications are allowed provided they replicate original panels and are designed to be visible. Audio speaker installation is prohibited in the headliner. Custom passenger door panels must not be taller than the OEM panel.
Notice – Competitors are strongly encouraged to have their installations neat in appearance, especially at National Finals. Recommended finish materials are: paint, carpet, Formica, Plexi, stainless steel, aluminum, and vinyl. Competitors taking the time to do so will be rewarded by having photos of their vehicles posted on the official website www.midwestspl.com and other forms of media used by Midwestspl.
3-13 Custom dashes must resemble the original dash in size, form, and function. Structural reinforcement is allowed only to those areas where aftermarket accessories, sound, or video systems are installed. Custom dash caps are permitted.
3-14 Custom center consoles are allowed as long as they are not designed to manipulate the interior of the vehicle to increase the competitor’s score. This will be at the discretion of the head judge.
Section 4 – Vehicle Requirements
4-1 Each vehicle must be capable of being registered, and licensed/tagged to drive on public roadways.
4-2 The vehicle must be capable of driving into the judging lanes.
Notice – If the vehicle breaks down at the show or on the way to the show, or if foul weather does not permit the driving or unloading of a vehicle, then the vehicle may enter the judging lanes by any means possible. This is at the sole discretion of the head judge.
4-3 Modifications to the body of the vehicle are not allowed if the modification will increase the vehicle’s interior volume. This includes, but is not limited to: cutting of the floor, wheel wells, and other areas that will change the interior volume of the vehicle. Air ride suspension modifications are allowed.
4-4 The judge must be able to see inside of the vehicle during the metering process to observe the metering equipment. This includes sides or the front window. If the window tint is considered too dark, the competitor may be asked to remove film in order to compete. Vehicles are not allowed to be covered at an event. Vehicles and systems must remain viewable to all competitors and spectators at National Finals. Vehicles may be shut or locked when not supervised.
4-5 People are allowed to hold or sit on the vehicle while being metered – provided no other rules are broken. The competitor takes responsibility for all parties involved.
Vehicles are allowed (1) 2” wide strap in Advanced and Mayhem divisions. Competitors will also be allowed (1) 12” long 2×4 per side of vehicle to brace at top of the door frame (under the strap), so long as the following requirements are met:
• Strap may not pass under the vehicle.
• A kill switch must be accessible outside the vehicle.
• No one may sit in, on, or push on the vehicle.
Sand bags, or heavy objects may not be used to externally brace the vehicle. Exception: Mayhem Division.
4-6 OEM or equivalent door and hatch seals must be in place. They may not be added to or modified, unless specified by a particular division.
4-7 Doors and windows may not be sealed (taped or siliconed shut) during the run unless otherwise noted. For safety reasons, if a competitor is known to break windshields, the competitor may tape their windshield prior to their run with the permission of the head judge to prevent breakage of glass or flying glass particles. We allow for one layer of transparent film and 2 layers of packing tape on side windows and windshield.
Exception – no more than 6″ of accumulated tape width per door is allowed to hold a side window from falling down during the run (not seal).
4-8 A competitor may switch vehicles at any point during the season.
4-9 National competitors may not share the same vehicle at the same event. However, they may create a “team name “ and run under that name. Only 1 vehicle per division may be assigned to a particular individual competitor and/or team per show.
Example: Competitor “A” may not share their vehicle with Competitor “B” at the same event. Also, Competitor A may not allow Team C to use their vehicle as a “team vehicle”. However, one competitor may use 1 vehicle in one division and another vehicle in a different division.
4-10 At indoor events – vehicles that produce an abundance of exhaust fumes, oil leaks, gas leaks, etc., (based upon unanimous vote of the judging staff), will either be required to compete without the engine running, or in worst case – prohibited from competing.
Section 5 – Equipment Requirements
5-1 The audio equipment must be designed for use in a 12-Volt automotive environment and available for purchase through a legitimate auto sound business.
5-2 Use of wireless remote controls, IR repeaters, bass knobs, and/or podiums are allowed in all classes.
5-3 The subwoofer(s) must be powered by the audio amplifier(s) in the vehicle.
5-4 The maximum voltage of the vehicle’s electrical system can not be higher than 15.5 volts in any national class during the entire run. Exception: Advanced and Mayhem Division (18 volt limit).
In most cases, this measurement will be taken at or near the amplifier. In some situations, due to install or other unforeseen issues, the measurement can be taken elsewhere. This is at the judge’s discretion.
Notice – battery/capacitors limitations & safety
• Aftermarket batteries are allowed.
• Capacitors are allowed
• Additional batteries may be mounted in a cargo area and/or under the hood. No battery boxes, trays or racks underneath the vehicle permitted. (Exception Mayhem Division)
• Vehicles with batteries installed, wired, and assembled in an unsafe manner, according to the judge, will not be permitted to compete.
• All 12V terminal connections will be required to be protected by durable, non-conductive material. I.E.: Wood, plastic, rubber. The use of multi-input adapters on amplifiers, i.e. dual inputs, must have the positive input protected by heatshrink or electrical tape.
• Competitors with lithium batteries installed MUST have a ABC Fire extinguisher in the lanes during run.
5-5 The use of aftermarket alternators and external voltage regulators are allowed – provided no other rules are violated. There is no limit on the number of alternators used.
5-6 External generators, battery chargers, and other charging devices (excluding primary vehicle’s alternators) may not be used in the judging lanes or while the vehicle is being metered.
5-7 Passive radiators are allowed – provided they are commercially available. They are not considered woofers and will not be counted as such.
5-8 Subwoofers installed in an isobaric configuration will be counted by cone area individually, (not as 1 woofer)
Section 6 – Installation Requirements
6-1 Nothing in the sound system may interfere with the normal daily use and/or operation of the vehicle. This includes equipment on the floor or seat and seating position of passengers. See specific divisions for details.
6-2 Amplifiers mounted in the passenger compartment must meet the following guidelines:
• Amplifiers may be installed under front or rear seats as long as the installation doesn’t interfere with normal operation of the seat
• Amplifiers may not be installed where the seat folds/lays directly on top of the amp.
• Amplifiers must be securely fastened and protected from unintentional damage or abuse.
6-3 No aftermarket sub amps and/or batteries may be mounted in the center console or center console area. However, mid/high amplifiers are allowed as long as no other rules are violated.
6-4 Additional batteries may not extend forward past the B-pillar in the passenger compartment – unless the space behind the seat is no longer considered “passenger” area. I.E.: walled vehicle. Extended cab trucks with seats folded for competition – this area is no longer considered “passenger” compartment.
6-5 Subwoofer(s) and subwoofer enclosures are required to be located behind the edge of the driver’s door to the edge of the passenger door, referred to as B-Pillar and/or door jamb.
Notice – The following test may be performed – “B” pillar test: A string is passed through both doors and ran up and down the door jamb. No part of the subwoofer enclosure or anything attached to the enclosure may interfere with this test. OEM trim panels attached to the enclosure are not counted.
Notice – Non-Wall Pickup Trucks :
• Single cab pickup trucks (not extended-cab or king-cab, and only those with 2 doors) with the subwoofer enclosure behind the front seats – the subwoofer enclosure can not be in front of the “B” pillar by more than 3” at any point.
• All other pickups (extended-cabs, king-cabs, or those with 3 or more seats, etc.) – the “B” pillar test is required.
• In the Basic Division, all equipment must reside within the cab of the vehicle except for batteries.
• In the Basic Division, full size trucks with forward facing rear seats – the enclosure shall be under, behind, or in front of the rear seat, but not on top of. Rear seats may be folded during competition but must be in its OEM location and not removed.
• In the Advanced No Wall Division, pickups are allowed to remove or modify any part of their back seats to incorporate the sound system. Enclosure, amps, and batteries may reside in the bed of the vehicle as long as the equipment doesn’t extend above the side bed rails.
Notice – Walled Pickup Trucks:
• In the Advanced Divisions, all equipment can be in the bed of the truck, provided a commercially available bed cover or camper shell is used.
6-6 Competitors are encouraged to mount/secure subwoofer enclosures and other equipment for safety.
6-7 The cargo area in vans and SUVs is defined as behind the second row seating. If the vehicle does not have second row seating in place, then that vehicle can not compete in the basic division unless otherwise noted.
6-8 In the Basic Division, two seat vehicles, such as CRX’s, EXP’s, RX7’s or Corvette’s – all equipment (excluding source unit, EQ, processors and battery under hood) must be behind the B-pillar and can’t be sitting behind the front seats on the floor. Equipment location is subject per division.
6-9 The following are definitions regarding box height per division:
Basic Division
Notice – Box Height: In the Basic Division, Midwestspl defines a speaker wall as any subwoofer enclosure and / or baffle board that meets one or more of the following conditions:
• Any subwoofer enclosure that is taller than the top of the rear seat back (not including head rests) or taller than the bottom of the rear side windows – whichever is lower.
• Anything that is attached to or sitting on the subwoofer enclosure – including, but not limited to, speakers, surrounds, amplifiers, processors etc., is considered to be a part of the subwoofer enclosure and will count towards the “wall” test.
• Any aftermarket audio components installed to increase the competitors SPL score, that is installed in non-OEM locations will be counted towards the wall test. Components installed for mids/highs purposes will be permitted upon judge’s discretion.
• If the vehicle is a two seat vehicle such as a CRX, EXP, RX7 or Corvette (excluding pickup trucks), then the maximum height of the enclosure shall be 16” measured at its tallest point from the bottom of the floor. Floor build-ups in relation to box height will be at the sole discretion of the head judge.
• Vehicles such as standard cab, extended cab, and king cab pickups – the maximum box height will be at the bottom of the rear window.
Advanced No Wall
Notice – Box Height: In the Advanced No Wall Division, many of the following rules and drawings are from the DBDRAG.
Midwestspl defines a speaker wall as any subwoofer enclosure and / or baffle board that meets one or more of the following conditions:
• Enclosures that are greater than 30 inches in height.
• Enclosures that encroach upon “Normal Use” requirements for the passenger compartment.
• Any installation which results in a vertical clearance between the top of the enclosure and the headliner of 13 inches or less. (This clearance requirement also applies to any equipment which may be mounted to the enclosure.)
Wall Test: The judge shall use a mic jig (or other appropriate measuring device) to verify a vertical clearance of 13 inches exists between the highest point on top of the enclosure (and any equipment attached to the enclosure) and the headliner directly above that point. (Please refer to Figure 15-1 through 5, 8 & 9 on pg. 14). The judge will select the highest point on the enclosure that is most advantageous to the competitor. This will normally be in the center of the vehicle.
The judge will then verify (if necessary) the height of the enclosure to ensure that it is less than 30 inches in height.
Wall Test Hatchback Examples:
Case 1 – The subwoofer enclosure is located ENTIRELY underneath the rear hatch OR the highest point on the enclosure is located underneath the hatch. In this example the judge will measure from the highest point on the enclosure (including amps, accessories, woofer surrounds, etc.) to the horizontal plane defined by a point located at the top center of the hatch opening. (Please refer to pg. 14 Figure 15-6, 15-7a, and 15-7b.)
Case 2 – The subwoofer enclosure is NOT located entirely underneath the rear hatch. In addition, the highest point on the enclosure is located directly beneath the headliner. In this case the standard wall test technique will be used. (From the highest point on the enclosure to the headliner.) Figures 15-6, 15-7a, and 15-7b on pg. 14 do NOT apply in this case.
6-10 Trunk vehicles may port through the rear deck utilizing existing openings only. Modifying or cutting the rear deck or OEM package tray cover is prohibited. The only allowed modification is the unbolting and laying forward of the back of the rear seat only in non-folding vehicles and/or removing rear speakers.
6-11 Competitors may install additional equipment in the spare tire well. This includes – but is not limited to: amps, batteries, wiring, speakers, and enclosures. This area must also be available for inspection.
6-12 There is no limit on the amount of sound damping. All sound damping must be installed in such a manner that the OEM door panel/panels and headliner must attach normally using the factory OEM tabs/screws. Rear deck lid or other places in the cargo area where there is not an OEM cover may be used. Sound damping must be used in accordance with the manufacturer’s recommendation. No sound damping shall be visible or placed on top of interior panels. Commercially available sound damping products such as roll on mat, spray, or expanding foam are considered approved materials. Home made sound damping materials are not allowed.
6-13 The use of tape, vinyl, or other adhesive tapes is not permitted within view of the passenger compartment or cargo area to hold panels in place, to seal gaps between panels, or to cover vents.
6-14 The use of, but not limited to, glue, silicone and/or additional screws is not permitted to attach OEM panels in place.
6-15 Competitors are required to secure all batteries and capacitors safely and securely.
6-16 Competitors may not share the same equipment unless one competitor is out of the competition.
6-17 All subwoofer speaker wires must be capable of being inspected from the sub amp to the enclosure. In the power divisions, competitors are also required to have all (+) positive speaker wires going to the enclosure(s) ran in such a way that they can all be clamped at one time.
6-18 In the power divisions, competitors are required to use only a single speaker wire (conductor) per output terminal on the amplifier. (When output distribution terminals are used, a maximum number of speaker terminals is 2). Speaker wire distribution blocks or connections may be used if the metering equipment can be placed between them and the amplifier.
6-19 Regarding Advanced 3, Kaos 4, Xtreme 4, and Mayhem – any material may be used for a roof build down – provided a string test can be performed from the opening of the driver and passenger door openings (excluding OEM headliner).
6-20 The use of (1) “ striper pole” interior brace may be used in Advanced 3, Kaos 4, and Xtreme 4 – provided the diameter does not exceed 3 inches.
Section 7 – Classification
7-1 Competitors are classified by the components of their sound system and modifications to the vehicle.
7-2 Subwoofers mounted behind the “B” pillar in the competitor’s vehicle will be counted to determine what class they can compete in. Subwoofers mounted in an OEM center console will not be counted.
7-3 In some classes, a power rating along with the sizes of subwoofers is used. The higher of the two ratings will determine a competitor’s class.
Example: Competitor “A” has 2-12” speakers and 2,000 watts. The entry level class allows for 2-12’s and 1,000 watts therefore the competitor would be moved up into the class that allows for 2,000 watts. However, competitors may choose to turn down their 2,000 watt amp to produce 1,000 watts of power during their run and remain in the entry level class.
Example: Competitor “B” has 1,000 watts and 4-12’s; this competitor would be in a larger class because of the number and size of subwoofers.
7-4 Each competitor may compete in only 1 class per division at a regular season event – as long as their particular audio system installation and vehicle regulations meet each class’s requirements. Exception: Mayhem division, the competitor can run both classes in the Mayhem division. See rule 11-3 regarding National FINALS participation.
Section 8 – Max Wattage
8-1 Some classes require a max wattage measurement to be taken. This is how max wattage is derived:
• Termlab Probe Meter voltage leads are placed on the speaker leads coming out of the amplifier.
• Termlab Probe Meter ammeter/current meter is “clamped” around the (+) speaker lead coming out of the amplifier to speaker lead(s). Competitors are asked to have these wires accessible.
• During the run, Termlab measures the wattage used to achieve the highest SPL (Sound Pressure Level).
• In the event of equipment failure, or other unforeseen circumstances, other power metering equipment may be used (I.E.: Flukes)
8-2 Competitors are encouraged to run the proper size speaker wire (or larger) and have it accessible to placement of the judging equipment. If wires are unable to be “pierced” or the judge feels they can not get a proper measurement, then the competitor must either run a non-power class or make changes if time permits.
8-3 In some cases, an amplifier’s power output may not be able to be recorded correctly due to unforeseen circumstances in the design of the amplifier and/or installation. When an issue arises, Midwestspl reserves the right to either not allow this particular amplifier or installation in its power class, or use additional measurement equipment and means to determine power. This will be judged on a case-by-case basis. Competitors are encouraged to use only amplifiers in which their power can be properly measured at an event.
Section 9 – Instructions per Division
Midwest Street Division
MSD – Classes are for beginner and entry level competitors only. Manufacturers, retailers, and professionals are prohibited from participating in these classes. This includes – but is not limited to: Anyone that has competed at any World/National FINALS, anyone that is a current member of another sound-off organization, or someone that has higher skills or knowledge than others in their class. Moving someone out of these classes is at the sole direction of the event promoter or judge. Local level rules and classes may vary from event to event. These are typically offered at most Midwestspl Events. All MSD competitors are required to play music (no tones or sweeps).
Typical classes offered (vary depending on the needs of the host):
• MSD 1 – Up to 1-12, 2-10’s, or 3-8’s (peak score)
• MSD 2 – Up to 1-15, 2-12’s, 3-10’s or 4-8’s (peak score)
• MSD 3 – Up to 1-18, 2-15’s, or 4-12’s (peak score)
• MSD 4 – Unlimited speakers (peak score)
The rules for the MSD are suggested rules, and can vary from show to show depending on the specific needs of the retailer/show promoter. The following rules are typical of what you will see:
• Doors and windows may be open
• Engine RPM limit 2000
• Parking brake must be set
• Walls are permitted
• Vehicles must have 2 front seats
Basic Division
Classes:
• Basic 1 – up to 1-15, 2-12’s, 3-10’s, 4-8’s, or 7-6.5’s, up to
1,000 watts (max clamped)
• Basic 2 – up to 1-24, 1-21, 1-18, 2-15’s, 4-12’s or 6-10’s, 9-8’s, 14-6.5’s up to 2,000 watts (max clamped)
• Basic 3 – unlimited speakers, up to 4,000 watts (max clamped)
• Basic 4 – unlimited speakers, up to 8,000 watts (max clamped)
• Basic Trunk – unlimited speakers, up to 4,000 watts (max clamped)
9-1 CRX’s, or any vehicle not originally designed for the US domestic market, are not allowed in Basic 1 or 2.
Midwestspl defines a vehicle not originally designed for the US domestic market as a vehicle not originally offered for widespread sale as new by an OEM (Original Equipment Manufacturer) in the United States. This includes, but is not limited to, Fiat Panda, Seat Marbella, and Seat Terra. Proof of OEM sale availability may be required upon inspection of vehicles in question.
9-1a Only solid trunk vehicles (not SUV or hatch) will be allowed to compete in Basic Trunk, they will not be permitted in any other class under the Basic Division. Solid trunk vehicles may continue to participate in the Xtreme and Kaos divisions.
9-2 Structural modifications to the passenger or cargo compartment are not permitted.
9-3 Custom installations and/or custom panels are permitted provided no other rules are violated.
9-4 Subwoofers and enclosures must be in the “cargo” area.
9-5 Subwoofers and enclosures may not sit on top of a folded rear or 2nd row seat.
9-6 Seats and seat backs must be fully functional when the enclosure is in its competition position. If the vehicle is an extended-cab or king-cab pickup truck, you do not need to be able to fold the rear (side or forward facing) seats as normal operation.
9-7 Enclosures may be “built” into the trunk of the vehicle. However, the construction may not be permanent, and the competitor must easily be able to return the vehicle to its original/OEM condition. Competitors may be asked to provide proof that the installation meets these guidelines.
9-8 Speaker walls are not permitted.
9-9 Any audio equipment used to produce SPL must be below the window line, (referred to as the wall test).
Exception: If the two seat vehicle has less than 24” of maximum B-pillar to back depth in the cargo area, then that vehicle may use all of the cargo area for the subwoofer enclosure and equipment installation, provided no other rules are broken.
9-10 Commercial vehicles, those with no rear 2nd or 3rd row seating, and/or have floor cuts, such as a handicap van or an ambulance, are not allowed.
9-11 Sensor placement in the legal position.
Advanced No Wall Division
Classes:
• Advanced No Wall – unlimited speakers / power
9-12 Structural modifications to the passenger compartment are not permitted in front of the “B” pillar. Interior modifications are allowed – provided the modification is behind the “B” pillar and under the “wall test”.
9-13 All windows and openings need to function normally in front of the “B” pillar and above the widow line.
9-14 Cut-throughs in pickups are permitted.
9-15 Speaker walls are not permitted.
9-16 Commercial vehicles that have floor cuts, such as a handicap van or an ambulance, are not allowed.
9-17 Two seat vehicles, such as a CRX, EXP, RX7, or Corvette, may have all equipment up to the B-pillar.
9-18 Sensor placement in the legal position.
Advanced Division
Classes:
• Advanced Trunk – unlimited speakers / unlimited power
• Advanced 1 – up to 1-24, 2-21’s, 2-18’s, 4-15’s, 6-12’s, 9-10’s, 14-8’s, 21-6.5’s, and up to 4,000 watts (max clamped)
• Advanced 2 -up to 2-24’s, 3-21’s, 4-18’s, 6-15’s, 9-12’s, 13-10’s, 21-8’s, 31-6.5’s, and up to 8,000 watts (max clamped)
• Advanced 3 – unlimited speakers / unlimited power
9-19 Structural modifications to the passenger compartment are not permitted in front of “B” pillar. Exception: Advanced 3, Kaos 4, Xtreme 4. See 6-20 for more info.
9-20 All windows and openings need to function normally in front of the “B” pillar (excluding sunroofs).
9-21 Speaker walls are permitted – but not required.
9-22 Two seat vehicles, such as a CRX, EXP, RX7, or Corvette, may have all equipment up to the B-pillar.
9-22a In Advanced Trunk, all equipment must be in trunk.
9-23 Sensor placement in the legal position.
Xtreme Division
Xtreme 1 & 2 use Basic rules, Xtreme 3 & 4 use Advanced rules for the following:
Classes:
• Xtreme 1 – up to 1-15, 2-12’s, 3-10’s, 4-8’s, or 7-6.5’s / unlimited power
• Xtreme 2 – unlimited speakers / unlimited power
• Xtreme 3 – up to 1-24, 2-21’s, 2-18’s, 4-15’s, 6-12’s, 9-10’s, 14-8’s, or 21-6.5’s / unlimited power
• Xtreme 4 – unlimited speakers / unlimited power
9-24 All passenger side doors must remain shut, but driver side door(s) can be open during the run. All windows can remain open, including the hatch or trunk.
9-25 Scores will be averaged for 30 seconds during the run.
9-26 Xtreme Division will measure the audio system’s SPL 12 inches from the opening of the front passenger’s door window, centered left to right of the window opening, level with the opening (window seal) outside of the vehicle.
9-27 Competitors/spectators may not crowd around or “cup” the sensor during the metering process. The distance away is up to the head judge. No more than 2 people are allowed “between the bumpers”, including the operator. No part of their upper body may come within 3′ of the mic stand. Competitors and teams are allowed to sit on top of the vehicle as long as no other rules are violated.
Kaos Division
Kaos 1 & 2 uses Basic Rules, Kaos 3 & 4 uses Advanced rules – except for the following:
Classes:
• Kaos 1 – Up to 1-15, 2-12’s, 3-10’s, 4-8’s, or 7-6.5’s / unlimited power
• Kaos 2 – unlimited speakers / unlimited power
• Kaos 3 – up to 1-24, 2-21’s, 2-18’s, 4-15’s, 6-12’s, 9-10’s, 14-8’s, or 21-6.5’s / unlimited power
• Kaos 4 – unlimited speakers / unlimited power
9-28 Scores will be averaged for 90 seconds during the run.
9-29 The SPL sensor will be placed inside the vehicle on the center of the windshield – (centered horizontally and vertically).
Mayhem Division
Mayhem Division will adhere to the general Midwestspl rules, except for the following changes:
Classes:
• Mayhem Max – unlimited speakers / unlimited power
• Mayhem Hertz – unlimited speakers / unlimited power
9-30 Interior modifications are REQUIRED. Modifications are allowed anywhere in the vehicle. Anything goes (floor cuts, battery boxes, double windshields, roof build downs, stripper poles, seat removal, wood floor, bolt doors shut, etc.) ONLY THOSE vehicles which have interior modifications that prohibit them from competing in any other Midwestpl class may participate in Mayhem.
9-31 The maximum voltage of the vehicle’s electrical system can not be higher than 18.0 volts during the entire run.
9-32 Sensor placement in the legal position.
9-33 Mayhem Hertz is a 30 second music average score from the legal mic position.
DEMOlition Division
DEMOlition Classes are for the competitor who wants to really show off to the crowd and generate excitement! These competitors do not accumulate points toward National Finals, and are non-metered (demo only) classes – based on a voting system with a cash payout and an entry fee of $25 each.
Classes:
• Pain Generator – B-pillar class
• Party Wagon – C-pillar class
• Face Melter – Stunt walls
Competitors may choose to enter a max of two classes, Face Melter plus Pain Generator or Party Wagon. Competitors earn points by collecting votes, which are purchased from the show promoter. Each vote costs one dollar. Contestants may vote for themselves, and there are no limits to the number of votes an individual may cast.
All votes are tallied by show officials. Total votes per class are tallied and monetary payouts are based on the total as follows”
• 1st 40%
• 2nd 10%
Demolition classes start at the beginning of the show. At National Finals, it will be held at the end of the event before trophies.
Additional Classes
At some events, these additional classes may also be offered. These classes are for fun and do not accumulate points toward National Finals.
• Loud N Low – This format requires the competitor to play 4 tones (20hz, 25hz, 30hz, & 35hz). The scores from these tones will be averaged together to achieve a final score. Sensor placement is in the center of the windshield, measured vertically and horizontally. Advanced Division rules apply.
• Top Dog – This format uses track 19 on the Midwestspl USB. The track highlights frequencies between 30-50hz. Competitors must play this track for at least 30 seconds while the computer takes an average score. Sensor placement is in the center of the windshield, measured vertically and horizontally. Advanced Division rules apply.
Section 10 – Other Information
10-1 All rules will be enforced based upon their intent, and the ruling of the head judge is final.
10-2 At times there may be certain rules or guidelines that are not printed in this rule book. There also may be times that certain rules need amended, modified, changed, reworded, or added to in an effort to keep within the spirit or intent of Midwestspl.
10-3 In some cases a competitor meeting will take place prior to the event. It is your responsibility to know the information discussed at this meeting. Meetings will be announced prior to the event date.
10-4 A competitor caught tampering with the judging equipment will be disqualified and removed from the event without refund.
10-5 A competitor caught deliberately cheating will be banned from competing at all Midwestspl events.
10-6 Groups or “teams” are encouraged to wear matching shirts or clothing in order to have a more professional appearance at events.
Section 11 – National Finals
11-1 Midwestspl National Invitational information can be found online at www.midwestspl.com, or you can contact our offices for further information.
11-2 Invitations to the Midwestspl National Finals will be awarded as follows:
• Competitors must earn the requested total number of points. For this season the total is 100.
• Competitors must earn 50 points to qualify in the class they wish to compete in at National Finals.
• Competitors must attend a minimum of 4 events during the season no matter how many points they earn to be eligible to attend National Finals.
• Competitors must be a member of Midwestspl to compete at National Finals.
• Example: A competitor can have 60 points in Basic 1 and 40 points in Xtreme 2 to equal 100 points. They would be able to participate in Basic 1 at National Finals. A competitor can have 60 points in Advanced 3 and 60 points in Xtreme 3 to equal 120 points. They would be able to participate in Advanced 3 and Xtreme 3 at National Finals.
11-3 Participation at National Finals:
• You may only compete in either 1 Basic class or 1 Advanced class at National Finals and/or:
• You may only compete in 1 Xtreme class
• You may only compete in 1 Kaos class
• You may compete in both Mayhem classes
11-4 Competitors must use their own vehicle or the vehicle they competed with the most during the year at National Finals.
11-5 The vehicle must carry valid insurance.
11-6 Photos of all vehicles, participants and attendees at National FINALS may be taken and posted on the main site www.midwestspl.com and on various other websites and used for marketing purposes.
Section 12 – Inspections & Protest
12-1 Vehicle inspections will take place at National Finals prior to qualifying. The registered competitor must be with their vehicle during this process. If an issue arises where judges need to address installation legality, only the registered competitor (not team or friends) may be involved in a private discussion. Team vehicles will designate one person to be the spokesperson.
12-2 Midwestspl and it’s judges reserve the right to audit a competitor’s vehicle. During an audit the competitor will be asked to show the vehicle and its audio sound system. If the competitor does not allow the judge to verify their vehicle then the competitor’s score shall be eliminated and the competitor disqualified from the event and no refund given.
12-3 Audits may include, but not be limited to, the following inspections:
• The vehicle’s electrical system
• The vehicle’s sound system
• The subwoofer enclosure
• The interior panels
• Competitor’s media
12-4 Competitors may protest another competitor at National Finals:
• Competitors may ONLY protest by filling out a protest form.
• You may only protest someone else in your class.
• Protest forms must be filled out completely.
• You must provide your name (or competitor number), the name of the competitor being protested, the rule in which they are in violation of, the action you would like to see taken, and the time.
• Judges will review each protest form as they are submitted and take action.
• After brackets are made, protest forms may ONLY be turned in as long as the violation has occurred AFTER the competitor has qualified. (I.E.: The competitor qualified legally, made changes and now is illegal).
Section 13 – State & National Records
13-1 State Records may be set at any event. The competitor’s highest qualifying or winning score of the event will be counted. Scores will be posted on the official website www.midwestspl.com. Certificates will be handed out at National Finals to those who have the current record at the end of the season. State Records will be reset at the start of the new season.
13-2 National Records may only be set at Progressive Events. The competitor’s qualifying or highest winning score of the event will be counted. Scores will be posted on the official website www.midwestspl.com. Plaques will be handed out at National Finals to those who have the current record at the end of the season. National Records WILL NOT be reset at the end of the season.
Section 14 – Points
14-1 Points will be awarded to competitors at an officially sanctioned Midwestspl event as follows:
• First Place: 20 Points
• Second Place: 15 Points
• Third Place: 12 Points
• Fourth through Eighth: 10 points
• Ninth & Below: 5 points
14-2 Progressive Event points value will reflect the total number of unique competitors:
• 1-19 unique competitors = 1X
• 20-29 unique competitors = 2X
• 30-39 unique competitors = 3X
• etc.
14-3 Individual Memberships
• Memberships must be purchased no later than Sept 30th.
• Points are tracked by the competitor’s name.
• A person may only purchase one membership for themself.
• You may NOT use a “team” name as your membership name.
• You do not need to be a member to accumulate points.
14-4 Team Memberships
• Must be a Team Member prior to accruing points at any event.
• All names of authorized operators of the team vehicle must be on the Team Membership card.
• Team Memberships are $55 per season (for 2 people). Each additional competitor will add $10.
• Team Memberships must be setup/bought by July 31st, (60 days prior to season cut off).
• Team Membership cards must be present upon registration at each event.
• Team Membership cards must specify a team vehicle.
• A $20 fee will apply to change team vehicle or change/add names on Team Membership Card.
14-5 Competitors may earn additional points by participating in multiple divisions at each event.
14-6 Points are non-transferable between competitors.
14-7 If Midwestspl feels that a particular event results are in error, Midwestspl has the right to modify that event results and competitors points accordingly.
Section 15 – Points Cup
This years Points Cup is sponsored by
Incriminator Audio (www.incriminatoraudio.com). The Points Cup is a race to see who can have the most points at the end of the season. After the conclusion of the season at Midwestspl National FINALS, the winner will be presented with the Incriminator Audio Points Cup for their achievement.
How to win: Attend as many shows as possible and enter as many classes as allowed.
Competitors points will only come from:
• (1) Basic or (1) Advanced class
• (1) Xtreme
• (1) Kaos
• (2) Mayhem
Incriminator Audio Points Cup points will be awarded as follows:
• 1st – 5 points
• 2nd – 3 points
• 3rd – 1 point
We will take the highest points from either Basic or Advanced class, but not both. Max points awarded from each show shall be 15 points.
Points Multiplier (Progressive Events) will not count towards the Points Cup.
“Midwestspl strives to offer a fun welcoming atmosphere while providing top-tier car audio competition.”
Andrew & Ashley McCullough
Owner – Midwestspl
www.midwestspl.com
- Davione Butler
2023 Incriminator Audio Points Cup Champion
2024 Competition Season - GP Car Audio
Title Sponsor for
2024 MidwestSPL Finals - Directronix
Ring Sponsor for
2024 MidwestSPL Finals - Incriminator Audio
Trophy Sponsor for
2024 MidwestSPL Finals - Assassin Wear
Badge/Lanyard Sponsor for
2024 MidwestSPL Finals - Team Savage Sounds
Progressive Event Sponsor for
2024 MidwestSPL Finals