ampeg svt 4 pro

[alansombr]

Hello good afternoon
Can someone please tell me a way to regulate the Bias ap101 and ap201

Channel A distorts

[nickb]

I'm really not sure what you are asking. I'm guessing English is not your native language so try writing in your own language as well as English and see if that helps.

It sounds like you have an SVT-4 Pro on which channel A is distorting. Try feeding the channel A preamp output to another amplifier to see how is sounds. That will at least tell us if the problem is in the preamp or the power amp.

Do you have much experience of electronics? What test equipment do you have?

[alansombr]

I'm really not sure what you are asking. I'm guessing English is not your native language so try writing in your own language as well as English and see if that helps.

It sounds like you have an SVT-4 Pro on which channel A is distorting. Try feeding the channel A preamp output to another amplifier to see how is sounds. That will at least tell us if the problem is in the preamp or the power amp.

Do you have much experience of electronics? What test equipment do you have?

Ok nickb, thanks

Yes, I did this test.
And the power, I think the bias is not regulated correctly
I changed the bias of 500R by 470R, because here in Brazil I find only 470r
I've been messing around for a while, but ampeg always takes a sura, I have a minipa

[alansombr]

I take the pre test to a friend on your ampeg svt 4 and the test was very well done and the pre works perfectly,
Can you tell me how to regulate the ap101 bias?
Can you tell me if they are mirrored ap101 and ap 201? Or each has an individual geogulation

[nickb]

Look at sheet 2. The bias setting instructions are on the center right.

Ampeg_SVT-4_PRO_Power_Amp_(07S428)_Schematics.pdf

If the bias is too high it will overheat, too low and you will get some distortion.
Have looked at the output waveform?
Have you tested the FETS?

[alansombr]

Look at sheet 2. The bias setting instructions are on the center right.

[ATTACH]44040[/ATTACH]

If the bias is too high it will overheat, too low and you will get some distortion.
Have looked at the output waveform?
Have you tested the FETS?

Ok thanks a lot
FETS are new
I'll regulate at 25mv (I'll try with my digital multimeter)
And I'll tell you again
My hp is burned, my son I call 220 and I have not looked at it yet
Thanks and sorry for the inconvenience and Good weekend

[alansombr]

Ok thanks a lot
FETS are new
I'll regulate at 25mv (I'll try with my digital multimeter)
And I'll tell you again
My hp is burned, my son I call 220 and I have not looked at it yet
Thanks and sorry for the inconvenience and Good weekend

I'm calling in a 150W bulb to regulate, okay to use a parallel bulb to regulate or I have to call

[nickb]

I'm not much of a believer in using a light bulb limiter for solid state amps. The transistors will blow faster than the the bulb heats up. I prefer to use a variac and monitor the current. If you have no other choice then 150W is too big. 40W is more like it.

[alansombr]

I'm not much of a believer in using a light bulb limiter for solid state amps. The transistors will blow faster than the the bulb heats up. I prefer to use a variac and monitor the current. If you have no other choice then 150W is too big. 40W is more like it.

ok

[alansombr]

I'm not much of a believer in using a light bulb limiter for solid state amps. The transistors will blow faster than the the bulb heats up. I prefer to use a variac and monitor the current. If you have no other choice then 150W is too big. 40W is more like it.

I think I have a 60 watt, okay?

[nickb]

I think I have a 60 watt, okay?

That would be OK.