Ive got one customer who like most is above all else in terms of extremity and the absolute limits of car audio. He has a PowerBass amp which he said is custom built not like th emainstream ones. I am working on getting a picture of this amp to post here, but have some 'upgrade' what-ifs and questions.
Supposedly this amp will run ~5000w at ~1ohm. The customer will be pushing 6x 15" subs with this amp for what I believe is for a 200A competition. He is asking me if there is any way to help monitor/maintain or even upgrade this amp for this type of use. First I told him was; any modifications throws warantee right out the window; which he was OK with that. Any experiments done would be for the satisfaction of the hobby for the both of us.
My thing about this amp and this type of competition focuses around voltage drop. Any voltage drop and amperage will rise; causing his 200A limit to blow and lose the competition. Voltage drop, most easily measured at the amp's power terminals is easy to monitor via a metered cap, and beefed up with batteries and whatnot. The owner wants to get ~2x ~14-16v batteries and alternator for what he is trying to do; which I believe is a good starting point and best way to move forward, but I have a different idea in mind for him and his amp...
My starting suggestion would be for him to monitor voltage drop not only at power terminals, but also the internal voltage at the rails with the idea behind voltage drop monitoring being done internally to the amplifier. With batteries and voltage staying high and constant into the amplifier, the next thing to monitor could definately be the power supply of the amplifier in the form of rail-voltage performance. From there, other options to keep things in tip-top condition and performance minded could be explored.
Has anyone tried doing anything like this?
Supposedly this amp will run ~5000w at ~1ohm. The customer will be pushing 6x 15" subs with this amp for what I believe is for a 200A competition. He is asking me if there is any way to help monitor/maintain or even upgrade this amp for this type of use. First I told him was; any modifications throws warantee right out the window; which he was OK with that. Any experiments done would be for the satisfaction of the hobby for the both of us.
My thing about this amp and this type of competition focuses around voltage drop. Any voltage drop and amperage will rise; causing his 200A limit to blow and lose the competition. Voltage drop, most easily measured at the amp's power terminals is easy to monitor via a metered cap, and beefed up with batteries and whatnot. The owner wants to get ~2x ~14-16v batteries and alternator for what he is trying to do; which I believe is a good starting point and best way to move forward, but I have a different idea in mind for him and his amp...
My starting suggestion would be for him to monitor voltage drop not only at power terminals, but also the internal voltage at the rails with the idea behind voltage drop monitoring being done internally to the amplifier. With batteries and voltage staying high and constant into the amplifier, the next thing to monitor could definately be the power supply of the amplifier in the form of rail-voltage performance. From there, other options to keep things in tip-top condition and performance minded could be explored.
Has anyone tried doing anything like this?
I'm assuming this is the amp? powerbass XTA 5000! (gut pics)
If so is it a db drag rule that he can't go above 200a?
If so is it a db drag rule that he can't go above 200a?
Its actually a Powerbass XTA 4000 which the owner says may already be modified.
New Powerbass xta-4000d power tests.
I was also way-way off with his fuse rating and spl class. He is not using 200A; he is using a 350A fuse but can use a second 350A. After talking with him more, he just goes to novice DB competitions and car shows at the moment so he actually does not do any DB dragging. He has a ~250A alternator and a single 14.4v battery (looking to get a second battery). I just thought I'd try doing some voodoo magic inside the amp if given the chance.
New Powerbass xta-4000d power tests.
I was also way-way off with his fuse rating and spl class. He is not using 200A; he is using a 350A fuse but can use a second 350A. After talking with him more, he just goes to novice DB competitions and car shows at the moment so he actually does not do any DB dragging. He has a ~250A alternator and a single 14.4v battery (looking to get a second battery). I just thought I'd try doing some voodoo magic inside the amp if given the chance.
Well the amp draw limit part is easy to get around...and it was done almost 20 years ago now. The trick is doing it so no one knows what your doing, and doing it correctly so all the extra horsepower does not take out the final stage of the monster amp.
This is akin to playing with dynamite Dr Zeus. If you do it wrong the amp won't survive very long at all, most probably less then one song play. But you don't have to worry about thermal roll-back this way lol.. right ?
The owner you speak of is thinking Max power and not max common sense and most probably lacks any formal education in electronics engineering and amplifier design. Think of a car amp like you would the rubber band in a rubber band toy. You wind it up and it goes, You wind it too tight and bang no more rubber band, and no more go either...
Re-designing and engineering a commercial product is top dollar work requiring that level of commitment and effort and is full of pitfalls and unexpected disasters to those lacking formal education in electronics design.
Remember everyone wants more then his money is worth...Always have, and always will. And unless he has bottomless pit pockets for wasted gear then your most likely going to have a short relationship with this client.
As for DB Drag people well I used to run a V-8 Vega 35 years ago, and it took every last free dime I had to support that thing. This is why I stopped dragging myself long ago. It akin to the picture i once saw of a Fancy dressed man in a tux walking down the wharf to his boat and just throwing bucket loads of money onto its deck as it fell out of his pockets... "If you want to do it, this is what its gonna cost. Can you handle that much financial dedication ? lol...
It can be done, is he ready to pay the price for what he asks. Oh and wait a minute while I warranty my Nascar ride I blew last week trying to do 225 going left all day long...lol.lol.lol...
Well this idea has been covered a million times on termpro and other well known db drag sites. He'd be better off buying some T4000.1bd amps used and have Rockford modify them for 18v input. I had four of these and when I was going to compete I called Rockford and they said they can modify them for 18v operation no problem for about 125 per amp. Then he can get a added alternator with a voltage regulator for 12v - 18v operation (Keep in mind this would only charge 18v batteries) then get a bank of 18v batteries for the rear separate from the rest of the car's electrical.
Sucks they limit the current usage but won't limit voltage, lol imagine that. All it takes is money to get around it so the guys with the most money have the first obvious advantage.
First people used electrical and box and tuning design knowledge to win. Then came the cheater amps and people with more money gained an advantage. Now they change the rules to allow wealthier competitors another advantage. Sad trend
First people used electrical and box and tuning design knowledge to win. Then came the cheater amps and people with more money gained an advantage. Now they change the rules to allow wealthier competitors another advantage. Sad trend
Power bass
Simple the claims of power are not possible.
There are 4 pcs of 49x19 toroids running at about 50KHz. Each is capable of 1,300w at 50KHz. This info is available from the MagInc site.
So theoretically 5200w is available assuming all circuits are 100% efficient which of course they are not. The class D output stage has massive saturation issues when driving 1 ohm.
The power supplies are also not 100% efficient.
I repaired one of these some months ago and at 14.4v battery it delivered just under 3,000w at 1 ohm
Steve Mantz
Zed Audio
Simple the claims of power are not possible.
There are 4 pcs of 49x19 toroids running at about 50KHz. Each is capable of 1,300w at 50KHz. This info is available from the MagInc site.
So theoretically 5200w is available assuming all circuits are 100% efficient which of course they are not. The class D output stage has massive saturation issues when driving 1 ohm.
The power supplies are also not 100% efficient.
I repaired one of these some months ago and at 14.4v battery it delivered just under 3,000w at 1 ohm
Steve Mantz
Zed Audio
Great input Steve! I love hearing from guys like you and Perry. Nothing beats hearing from the designers themselves. I never realized the toroids were running that kind of power at 50khz. The companies rate the amps at 5k but what hz are they testing it at? Is there a industry standard?
This would be a nice concept but there have always been people who could buy the top end $ "cheater" amps that were labeled "50w into four ohms" and four feet long. :lol: That was the way wealthy people got around the rules back then, now that current limiting rules exist it irks me that they won't limit the alternator voltage as well. They know damn well the wealthiest are going to use that to their advantage and still don't modify that rule? This is CAR audio competition, not airplane audio competition. How many people do you know that drive cars that operate higher than 14v on a daily basis. Heck, we could just run an extension cord to the car and use 110vac for the entire audio system in the car, then you wouldn't have to worry about the amperage limit. :lol:
When you go by power "class" and actually give everyone the chance to showcase their design skills vs pocketbook capabilities its a little more level is all I'm saying. I know you can't get around some advantages but a current limit without voltage limit is ludicrous. They should just label it the "people who can afford to run higher than 14v class" because they know that is what will happen for the winners. People who adhere to the 200 amp limit (for example) will pretty much lose in spl comps unless someone with a deeper pocketbook slips up and has a crappy design/setup with their 18-20v system. I'm not saying "stopping all forms of competition" makes any sense and I wish you wouldn't imply that's what I was inferring. I'm just saying the rule makers should have to adhere to some rules as well.
@ppi, cheater amps have no place any more because there are no watt classes. SQ is still using the classes but the power itself has nothing to do with winning. SQ is all about following every rule in the code book of iasca and or db drag. The classes are done by woofer area and other criteria such as bass race which has to do with precision and longevity. The only competition that power has any play in is spl and spl classes are divided by woofer area and then by vehicle modding like extreme where you can have 6" lexan windows and cement floors.
I'm not referring to SQ competition regulations, only the one (amperage) regulation the OP was mentioning.
SQ to me is the only real realm of audio competition nowadays in my opinion.
SPL competition (in my opinion)is a joke and you could probably build a neodymium magnetized 4" thick solid 45" inch piston with no surround, connected to a 50" chamber with four non-functional wheels and a steering wheel inside with the mic mounted to it, and drive it with a 40hz sine wave from an uber high power AC inverter and call it a "test tone" with the stuff people consider music lately. :lol:
Well, since my first post was referring to the OP's subject and then went into the realm of people using 16v+ alternators I'm not really arguing using cheater amps. I was just using them as examples from the past. The point I was trying to make is you can't have a relatively level "playing field" when some people have access to more expensive modifications (such as the apparently unregulated alternator voltage) some competitors utilize. If that is okay by rules then wouldn't it be okay for someone to run 1megawatt 120vac generator right next to their car and connect them with some nice thick cables, allowing them to run massive high voltage high end home amplifiers in their car with relatively low current? :lol: I mean, the guys are running modified high voltage alternators in their car that don't get used in streetable car so where does it end, why not?
I'm not complaining for myself, I haven't been involved in audio competitions since the late 90's but it just seems like a simple tweek could be done to keep people from abusing rules, especially if you're going to set some arbitrary amperage limit. If you're going to create "rules", make them to apply to everyone involved.
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