Need advice on fried amps on truaudio pht-sub15

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Plexlove

Audiophyte
Ok, so here is the deal...I purchased 2 of these truaudio pht-sub15 powered woofers from a guy a few hours away for $300 each....I spent days researching and even wrote the company but its hopeless finding any info really except that they are about 9 years old, can only be bought from an authorized dealer, 1000 watt Rms amp, and cost $2600 when released.
So I bought these knowing there was an issue with the amps but the guy swore he never pulled them or did anything except unplug them.
So I figured it would be a possible easy fix ....well...met the guy and loaded them up and got home and began my tear down.
For starters, these are some of the beefiest active subs Ive ever seen...the sub itself is way better built than expected, weighs around 25lbs, the cabinet is built as good as can be...internal bracing, double 3/4mdf, weighs around 60lbs im guessing....and the amp...dear god I was not expecting to see what I saw...
I began leaning it out to disconnect wires and want ready for the weight...the amp weighs 20lbs easy...HUGE toroidal transformer!
So before I even could get a look at it I knew it was bad, burnt metal smell something awful!
Got her out and the board was absolutely black! Completely fried to the point there was a hole in the board were one of the wire harnesses connected.
So cleaned it all up and took pics...and started trying to see if I could find a replacement board or something...no luck.
So....I figured id get advice from people who know about this stuff.
I can work on the basic stuff, replace bad caps, and stuff like that but im not knowledgeable enough yet to know how I should proceed.
I would really like to get these amps fixed (both fried exactly the same) but I think they are beyond repair...but the transformers are good, I tested them and they are just fine so that's a plus.
Not like I would know what to do with them but figured I could sell them and that would help recoup the cost of new amps or repairs.
Apparently they sell for about $350 each so at least that's a positive.
So I guess what im wanting to know is if there is a way to locate the original manufacturer of an amp? Or a way to get one repaired that is this bad?
If not, any recommendations on an amp that could power them?
I don't have tons of money to throw down atm so trying to figure something semi cheap out Lol
The sub is 6ohm, I have them hooked up to a 1000 watt Rms car amp ran parallel so the amps pushing them at 3ohms ...so roughly seeing around 300 to 400 Watts each when cranked...and honestly im blown away...completely!
They are night and day different from my 2 jbl pb12's.
For starters, they are clean and tight...no boomyness, no distortion, all the bass moves fluidly through the frequencies and they go a lot lower...down to 18hz I believe.
With the power im giving them now they are working a little over half way id say by looking...I don't really care to go near the full 1k...but would like to get 800 or so. Right now they are too much even at low wattage.
So any advice would be great on what I should do.
I also have a jamo THX dD6 sub as well with a faulty amp but it doesn't have anything visually wrong with it so any advice on someone or somewhere that does cheap repairs?
And lastly, any idea what I should do with the transformers? They are keen ocean 0-115+0-115 input, output 50-0-50 10a, 14-0-14 1a, 0-15 2a, 130 deg c. Thermal protection, says its 1000 Watts on it too...not 1000va...Watts.
I don't know enough about them to begin working on something...I read about a lot of people building their own pus, or amps with these as a basis...but read a couple forums where people said this size was more than any home amp will ever need.
 

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shadyJ

Speaker of the House
Staff member
I think those amps are shot. Unless they were struck by lightning, it may be that the problem stemmed from a design flaw, in which case fixing it would only be a short term solution until it occurred again. I would get an outboard amplifier and use it to power these subs. Use the plate amp only to fill in the cut out. Install some binding posts in the cabinet to connect to an exterior amp.
 
KenM10759

KenM10759

Audioholic Samurai
I've replaced the plate amps on a couple of subs with ones from Parts-Express.com and very happy. For one without DSP you can be under $200 for it. I think the DSP-equipped amps are worth the extra expense to get the total control, but that's me.
 
highfigh

highfigh

Seriously, I have no life.
It's rare that a board would have holes in it just from the components failing unless they were able to burn for a long time. That was a catastrophic failure and that kind of thing often comes from a lightning strike but I would assume the transformer would have gone away, too. I'm not confident that the parts will be available- they're not in business to sell parts and that model has probably been discontinued.

You could use a MiniDSP and separate amp- it would probably be less expensive than finding the same model of amp that's in this.
 
Pogre

Pogre

Audioholic Slumlord
I think those amps are shot. Unless they were struck by lightning, it may be that the problem stemmed from a design flaw, in which case fixing it would only be a short term solution until it occurred again. I would get an outboard amplifier and use it to power these subs. Use the plate amp only to fill in the cut out. Install some binding posts in the cabinet to connect to an exterior amp.
This, I think is your best bet. Pop the old amp back in just to seal it back up and go with an outboard.
 
P

Plexlove

Audiophyte
Yeah I fairly certain lightning was the cause since both amps fried exactly the same way...there is no fuses on the boards at all, only one that is in a slide out on the ac power input and they were blown on both amps...Idk that much about it but I just figured by the severity of it all, the fact they both are fried the same way, and the input fuses blown,...that lighting may have hit and perhaps enough current passed through in the split second it took the fuses to blow, and that caused the frying of the boards.
Like I said, Idk too much, learning more daily, but I researched more last night about testing the transformer and I believe they are just fine.
There are 7 input wires (in order counterclockwise...red, red, blk, blk, blue, brwn, brwn) and 8 output wires (or, or, y, blk, y, red, white, red)
With the info I gathered on this, I tested resistance of each winding and got this...
I have 0.3 ohms from input side on red to red, blk to blk, and brwn to brwn.
I have 1.3 ohms from red to blk and blue to brwn.
On output I have 0.5 ohms or to or and reds to white, 0.6 from red to red, 0.7 from yellows to blk, 1.2 from y to y.
Checked for continuity between all windings and there were no shorts.
Granted my dmm is nothing fancy and may not be dead accurate but from my understanding...the windings all read what they should and nothing seemed outta the ordinary.
I removed the metal plate on top to look it over and it looks brand new, even the plastic wrapped around it is mint.
Is there anything else I should look for to make sure they are good? I don't want to sell them on ebay if there is a chance they are faulty?
 

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Kingnoob

Kingnoob

Audioholic Samurai
Ok, so here is the deal...I purchased 2 of these truaudio pht-sub15 powered woofers from a guy a few hours away for $300 each....I spent days researching and even wrote the company but its hopeless finding any info really except that they are about 9 years old, can only be bought from an authorized dealer, 1000 watt Rms amp, and cost $2600 when released.
So I bought these knowing there was an issue with the amps but the guy swore he never pulled them or did anything except unplug them.
So I figured it would be a possible easy fix ....well...met the guy and loaded them up and got home and began my tear down.
For starters, these are some of the beefiest active subs Ive ever seen...the sub itself is way better built than expected, weighs around 25lbs, the cabinet is built as good as can be...internal bracing, double 3/4mdf, weighs around 60lbs im guessing....and the amp...dear god I was not expecting to see what I saw...
I began leaning it out to disconnect wires and want ready for the weight...the amp weighs 20lbs easy...HUGE toroidal transformer!
So before I even could get a look at it I knew it was bad, burnt metal smell something awful!
Got her out and the board was absolutely black! Completely fried to the point there was a hole in the board were one of the wire harnesses connected.
So cleaned it all up and took pics...and started trying to see if I could find a replacement board or something...no luck.
So....I figured id get advice from people who know about this stuff.
I can work on the basic stuff, replace bad caps, and stuff like that but im not knowledgeable enough yet to know how I should proceed.
I would really like to get these amps fixed (both fried exactly the same) but I think they are beyond repair...but the transformers are good, I tested them and they are just fine so that's a plus.
Not like I would know what to do with them but figured I could sell them and that would help recoup the cost of new amps or repairs.
Apparently they sell for about $350 each so at least that's a positive.
So I guess what im wanting to know is if there is a way to locate the original manufacturer of an amp? Or a way to get one repaired that is this bad?
If not, any recommendations on an amp that could power them?
I don't have tons of money to throw down atm so trying to figure something semi cheap out Lol
The sub is 6ohm, I have them hooked up to a 1000 watt Rms car amp ran parallel so the amps pushing them at 3ohms ...so roughly seeing around 300 to 400 Watts each when cranked...and honestly im blown away...completely!
They are night and day different from my 2 jbl pb12's.
For starters, they are clean and tight...no boomyness, no distortion, all the bass moves fluidly through the frequencies and they go a lot lower...down to 18hz I believe.
With the power im giving them now they are working a little over half way id say by looking...I don't really care to go near the full 1k...but would like to get 800 or so. Right now they are too much even at low wattage.
So any advice would be great on what I should do.
I also have a jamo THX dD6 sub as well with a faulty amp but it doesn't have anything visually wrong with it so any advice on someone or somewhere that does cheap repairs?
And lastly, any idea what I should do with the transformers? They are keen ocean 0-115+0-115 input, output 50-0-50 10a, 14-0-14 1a, 0-15 2a, 130 deg c. Thermal protection, says its 1000 Watts on it too...not 1000va...Watts.
I don't know enough about them to begin working on something...I read about a lot of people building their own pus, or amps with these as a basis...but read a couple forums where people said this size was more than any home amp will ever need.
Get a pro amplifier or something, what’s that big circle ️ thing with copper wire or something?? Called


Ultimate bass lover !! si ht15 dvc.
Free the reptile aliens
 
KenM10759

KenM10759

Audioholic Samurai
Get a pro amplifier or something, what’s that big circle ️ thing with copper wire or something?? Called


Ultimate bass lover !! si ht15 dvc.
Free the reptile aliens
It's called a toroidal transformer. They're used often in class A/B amps, and can be quite valuable depending upon the build quality. :)
 
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