Avalon vt-737sp

[Jdm5149]

K. I tested red wire to output knob on sp64. 1.23v. Black wire sp63 .343v but if I max out output knob it reachs 1.23v.

 

[Jdm5149]

Meter still not moving. Think I might redo some parts on the i/o card.

 

[Jdm5149]

K when testing line T11 : .187v. Same as sp16. T12 : 1.042v. Same as sp64. Red wire. Output jack red wire : .062v / .424 variations. Not steady. Black wire : .424v

 

[TheseGoToEleven]

K. I tested red wire to output knob on sp64. 1.23v. Black wire sp63 .343v but if I max out output knob it reachs 1.23v.

That sounds ok. Solder point 64 is the signal into the Output knob and solder point 63 is the same signal after attenuation (which is none if the knob is maxed). I have to correct my notes, as I had the output knob solder points written as 64 up to 67 when they are actually 64 down to 61.

 

[Jdm5149]

Making progress I guess. Is the i/o card between points 63,64 and the output xlr.

 

[Jdm5149]

Wow!! Signal thru to console from mic and line. But no movement from meter. I know the meter lamps are out. Only when I press meter switch does it move. Sometimes pins and sometimes just fluctuates. But definitely didn’t have this last week. The output xlr still shows the red wire sometimes jumping from higher to lower voltage. Is that correct. ?

 

[Jdm5149]

Will order pots for the attack and release which are compromising the vu

 

[Jdm5149]

Seems compressor might not be working. Don’t see reduction

 

[TheseGoToEleven]

The output xlr still shows the red wire sometimes jumping from higher to lower voltage. Is that correct. ?

Red and black XLR line out wires (solder points 7 & 8) should measure the same. I wonder if it is just a flaky connection somewhere. If you probe solder point 7 is the reading steady? If not, press the phase button in. Does that make 7 ok and 8 become unsteady instead?

 

[Jdm5149]

Will do tomorrow. Compressor definitely doesn’t seem to respond. All eqs seem to work. It could be my test lead or solder. I definitely didn’t have this last week thru console. Even instrument works. Gotta get those pots so I can calibrate meter. The unit was very dirty inside. Anything like acetone to clean boards maybe? People say they don’t really use the compressor but I would like to hear it for myself. But really excited I got it somewhat going.

 

[pucho812]

Will do tomorrow. Compressor definitely doesn’t seem to respond. All eqs seem to work. It could be my test lead or solder. I definitely didn’t have this last week thru console. Even instrument works. Gotta get those pots so I can calibrate meter. The unit was very dirty inside. Anything like acetone to clean boards maybe? People say they don’t really use the compressor but I would like to hear it for myself. But really excited I got it somewhat going.

I’ll do the pitch for a second.
Some don’t like the compressor, it’s not for everyone. Dr Dre for example used the compressor exclusively and often used a 1073 for the pre and eq.
How is that. I seen it. He mentions it in print as well.
Pitch over.

Tech time.
Check the value of C5 a lytic on the 7374 compressor board.
Depending on manufacturing year, it will be one of 3 values 10uf, 2.2uf or 1uF.
This changes the range of attack time. The bigger the cap the slower the attack. A 10uF is very slow like a Fairchild.
Units made after 2007 have the babyface mod which is a value of 1uF in that spots.
Older units will have either 2.2 or 10uF. Dre’s unit as others have 1uF installed. It’s a nice difference. I have played with the idea of a vintage/modern switch which basically would switch cap values as one position would be 10uF the other position 1uF. I tried it and it works but I could never find a good spot to mount it.
You can also change the release range, C4 on the same board. I have notes where it should be either a 5uF or 2.2uF. It may even be 1uF.
Most never do release, only attack.

 

[kags]

I’ll do the pitch for a second.
Some don’t like the compressor, it’s not for everyone. Dr Dre for example used the compressor exclusively and often used a 1073 for the pre and eq.
How is that. I seen it. He mentions it in print as well.
Pitch over.

Tech time.
Check the value of C5 a lytic on the 7374 compressor board.
Depending on manufacturing year, it will be one of 3 values 10uf, 2.2uf or 1uF.
This changes the range of attack time. The bigger the cap the slower the attack. A 10uF is very slow like a Fairchild.
Units made after 2007 have the babyface mod which is a value of 1uF in that spots.
Older units will have either 2.2 or 10uF. Dre’s unit as others have 1uF installed. It’s a nice difference. I have played with the idea of a vintage/modern switch which basically would switch cap values as one position would be 10uF the other position 1uF. I tried it and it works but I could never find a good spot to mount it.
You can also change the release range, C4 on the same board. I have notes where it should be either a 5uF or 2.2uF. It may even be 1uF.
Most never do release, only attack.

Avalon quotes the attack time range from 2ms to 200ms (Fairchild is 10x faster, I believe, though they might not sound it). I always find the attack too slow, even all the way fast. It's a transparent compressor and can never really hurt anything, which is why a lot of producers and artists like it. I find the preamp a little bland for vocals, but I love the pre for voiceover and the inst input for bass—especially with the LF boost! I occasionally use the comp, but if I want to hear the compression I patch in something else - either a VacRac or 1176 or LA2a.

 

[Jdm5149]

K. Thanks. I need to replace the attack and release pots. Are those available from Avalon

 

[pucho812]

Avalon quotes the attack time range from 2ms to 200ms (Fairchild is 10x faster, I believe, though they might not sound it). I always find the attack too slow, even all the way fast. It's a transparent compressor and can never really hurt anything, which is why a lot of producers and artists like it. I find the preamp a little bland for vocals, but I love the pre for voiceover and the inst input for bass—especially with the LF boost! I occasionally use the comp, but if I want to hear the compression I patch in something else - either a VacRac or 1176 or LA2a.

The Fairchild comparison was a quote from the designer but I see what you are saying.

 

[pucho812]

K. Thanks. I need to replace the attack and release pots. Are those available from Avalon

I am sure they are

 

[Jdm5149]

These?https://www.studioelectronics.biz/sunshop/index.php?l=product_list&c=200

 

[pucho812]

Those are the older version of pots
The switched over to BI not long ago.
You can use those if they are the correct values

 

[Jdm5149]

K. Got to adjust vu and it’s set to zero. Still no compressor action. When I do disengage meter switch it pins hard left. No action at all but signal is passing thru. I checked those caps and were reading good. C2 and C3 are not there.

 

[pucho812]

K. Got to adjust vu and it’s set to zero. Still no compressor action. When I do disengage meter switch it pins hard left. No action at all but signal is passing thru. I checked those caps and were reading good. C2 and C3 are not there.

What? C2 and c3? What board are you working on now? Sorry you have been all over this thing and I can’t keep up. Can you start referencing pcb numbers they will most likely be 5600-73xx

 

[Jdm5149]

Sorry. Seems all working except for compression. On the board u stated was 7374. The compression board. C5 is a 4.7/63v. Tested good