Ba2000 right channel sounds very distorted

[Overundr1]

Oops, well, we have all been down that road before.
The one 46vdc reading is incorrect, will deal with that later
I reccomend pulling the outputs and testing them first.
Anyways, subs are 2SC1403A --- MJ15003G 2SA745 --- MJ15004G
Don't forget to order extra to-3 mica's
When you get finished you should be good to go for the next 30 years with a better than new piece, hang in there.
-Lee

 

[sansuibutch]

Thanks Lee. All the fusses are good. I knew that 46 volts couldn't of been right figuring every other one was higher and it's on the right channel so kinda figured. But man is that frustrating since I checked the voltages before and never had a problem. I guess I'm learning how sensitive these outputs are. Do I have to replace all of them? I read replacing only half of them will make it not function correctly but wouldn't mind some conformation. And is there some parts I should order along with them since we now know that one voltage was low? Thanks again for all the help

 

[sansuibutch]

Oops, well, we have all been down that road before.
The one 46vdc reading is incorrect, will deal with that later
I reccomend pulling the outputs and testing them first.
Anyways, subs are 2SC1403A --- MJ15003G 2SA745 --- MJ15004G
Don't forget to order extra to-3 mica's
When you get finished you should be good to go for the next 30 years with a better than new piece, hang in there.
-Lee

I'm guessing the first one is the ones I need and the same variation of these for the other ones.. are the first ones the ones I need?

 

[Overundr1]

yes. I would replace all of them, both channels.

 

[Overundr1]

Too funny, I think you jinxed me, now I have an amp I am working on that won't bias up in one channel. Enough shop work for today, going to start backtracking voltages on Tuesday. Btw, while you wait for the new outputs to arrive, and since we are both having so much fun how about pulling all the outputs and taking some voltage readings while the amp is on a dbt where the wires enter the amplifier blocks. If you have any blue painters tape it is a good idea to position and then tape the output sockets in place on the heat sinks so there is no chance they can come in contact with the heat sink metal while you move things around. Been there too, full main cap discharge whilst in close contact with a dmm probe tends to require a sudden restroom trip afterwards along with unwanted significant other attention

 

[sansuibutch]

Too funny, I think you jinxed me, now I have an amp I am working on that won't bias up in one channel. Enough shop work for today, going to start backtracking voltages on Tuesday. Btw, while you wait for the new outputs to arrive, and since we are both having so much fun how about pulling all the outputs and taking some voltage readings while the amp is on a dbt where the wires enter the amplifier blocks. If you have any blue painters tape it is a good idea to position and then tape the output sockets in place on the heat sinks so there is no chance they can come in contact with the heat sink metal while you move things around. Been there too, full main cap discharge whilst in close contact with a dmm probe tends to require a sudden restroom trip afterwards along with unwanted significant other attention

I pulled the final stages out and with the multimeter checked the continuity between the blue and then the red wires to ground. On the left channel the blue wire is at .8 ohms and the rest read open. So I figure I cooked the two closest to the back of the amplifier. The thing that really has me thinking is I swear I was measuring the voltage on the red wire left channel when it happened. Are you saying I can safely fire this thing up without the final stage in circuit to test for voltage?

 

[Overundr1]

Yes, perfectly safe to run this amp with the outputs removed. Not all amps qualify however.

 

[sansuibutch]

Awsome I did not know that. I turned it on and I heard what I thought was the output relay click like normal but it stayed in protection mode..Im guessing that's because the outputs are missing. Anyway the voltage readings were 56.56 volts on three of the points and on the last one wich is the blue wire for the right channel it only has 41.6v. Since the distortion is in the right channel it all makes sense. I read these when I first pulled this apart months ago and must not of mentioned it on here. And thank you again for the help. I appreciate every bit.

 

[sansuibutch]

I'm pretty positive I finally figured it out. I pulled out the rectifier board along with the main filter caps. I haven't separated them yet but when I look between the board and the caps I can see one of the screws is missing in one cap.. and of course feeds ther right channel. Now to pull this apart without getting a buzz. Do I use a small resistor to short them out.? Well I have it apart is there a way a amateur can check thesent caps?

 

[sansuibutch]

So after all the time I have in this amp. It seems it was just a missing screw. I ordered the outputs today so they should be here soon. This amp should pretty close to new with all the replaced parts. I really hope there is a way to check these caps and there good. I have a good amount of money in parts in this thing as it is.

 

[mroboto]

I used these 18000uf 75V in my AU-11000A , hard to find beter.

http://www.digikey.ca/product-detail/en/united-chemi-con/E36D750MLN183TC79M/565-3331-ND/2095945

http://www.mouser.com/ProductDetail...750MLN183TC79M/?qs=p6VZ%2bklCkRSHDuuFIz/0Vw==

If you do so, you have to make ply in the brackets to fit the terminals,

Edit, but they seems to be unavailable now

 

[sansuibutch]

I used these 18000uf 75V in my AU-11000A , hard to find beter.

http://www.digikey.ca/product-detail/en/united-chemi-con/E36D750MLN183TC79M/565-3331-ND/2095945

http://www.mouser.com/ProductDetail/United-Chemi-Con/E36D750MLN183TC79M/?qs=p6VZ%2bklCkRSHDuuFIz/0Vw==

If you do so, you have to make ply in the brackets to fit the terminals,

Edit, but they seems to be unavailable now

Damn. I was looking on mouser earlier for some and they seem to be kinda big bucks. Is there an easyou way to test these ,or do I need some expensive equipment?

 

[mroboto]

Will cost more buying equipment to test them than changing them.

ESR tester, Capacitance and Leakage tester...

 

[sansuibutch]

Will cost more buying equipment to test them than changing them.

ESR tester, Capacitance and Leakage tester...

I will look around for some. If I can't find them a try a reasonable price I will toss a screw in there. I'd really like to replace them specially as far as I've come with this amp. What are the chances these caps are even close to there original value? I've never replaced any this big.

 

[Hyperion]

I will look around for some. If I can't find them a try a reasonable price I will toss a screw in there. I'd really like to replace them specially as far as I've come with this amp. What are the chances these caps are even close to there original value? I've never replaced any this big.

Why don't you re-fit them and use them, measure the ripple voltage, even with the amp at idle that can be enough to give a reasonable idea if they are ok.

And - how does it sound? - at least one channel sounded ok with the originals...

You will have to replace them eventually, but there might be a year or two of life in them.

 

[sansuibutch]

Why don't you re-fit them and use them, measure the ripple voltage, even with the amp at idle that can be enough to give a reasonable idea if they are ok.

And - how does it sound? - at least one channel sounded ok with the originals...

You will have to replace them eventually, but there might be a year or two of life in them.

The left channel sounded great. I guess I will throw them back in. I'd rather replace now that I'm in here but it's not to big of a deal to pull them later. Will I know if there no good while listening to it? I'm guessing if there shot I will have poor low end. Is it easy to test the ripple current?

 

[sansuibutch]

How should I go about discharging these to pull apart?

 

[mroboto]

Test their DC voltage to know if they need to be discharged.

To discharge, simply short them using isolated handles pliers or gloves to handle metal pliers.

 

[sansuibutch]

None are leaky or swelled so I'll replace that screw and reassemble and check voltage again at them 4 points. Thanx Mroboto

 

[Overundr1]

Um, not the way I would discharge them. If you have a dummy load handy hold that with the pliers and apply the ends of the dummy load to the terminals. Another way I have approached the bigger main caps is I have a 100w lightbulb with leads soldered to the edge and base with alligator clips on the ends and use that to discharge them.