New API 525 build thread.

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Cool - for a cheap quick build you should get a pair of the level loc pcbs. 
I just finished them and they are really nice in parallel and do things a little more extreme than my others - when that's what you want. And they come with a blend.
I did a shoot out on drums with all my diy compressors (33609, la3a, 525, 1176d, pico, SSL mixbuzz, level loc) and they were all different and all really cool.
I'd like to do it again and get some samples to post.
 
Yes, the "Original" API speed is good either for slamming or for catching naughty undesirable fast transients (eg. de-essing or some weird pops or to catch that very fast snare attack so you don't clip whatever comes next in the chain).

With mod attack it becomes a hell of a nice shaping tool (even though the release speeds are - sometimes - a bit of a let down) with lots of colour and attitude.

Never used it as parallel compression (crushing) but I'm sure the colour would be amazing.
 
even though the release speeds are - sometimes - a bit of a let down
Another interesting (possible) mod would be to go from the 2 switches (four release options: 1Meg, 5.7Meg, 20Meg, 24.7Meg) to a pot, like this one:
http://www.mouser.com/ProductDetail/Honeywell/485025M8843/?qs=FQNPYlYYPkaMq4TukLNTUw%3d%3d

 
so everything i need in addition to the kit is the lundahl trafo and the parts of the bom, right?
btw what does swmtr mean ? (i am new to 500 modules) ;)
 
weiss said:
so everything i need in addition to the kit is the lundahl trafo and the parts of the bom, right?
btw what does swmtr mean ? (i am new to 500 modules) ;)
swmtr refers to the PCB that contains the grayhill switch and meter circuit.

yes ,  you will need to aquire most of the components listed in the bom.  The lundahl is not needed if you choose to build the input opamp pcb.
 
Hey guys,

Been a while since I posted, as I've haven't really had much time for DIY for the last year, but thought I should at least report on another successfully built pair after finally getting around to finishing these after leaving them half completed on a shelf for six months. Anyway, I know Pete's only doing special runs now, so unlikely to be much activity, but just in case anyone does come across this again, it's really straightforward but just a few things that might help:

- The input and output pots require their cw / ccw swapping when being wired up. It was mentioned by one person and one person only earlier in this thread, so I didn't do it when I wired my first unit. Once I tried using it, it was indeed counter-intuitive, so I swapped them on my second one and had to go back and redo my first which was a bit of a pain (actually broke a pot, but luckily had a spare), so you can save yourself some work by doing it right the first time. I've never used the original units, so don't know whether that's a quirk of the original units or not.

- The "term" jumper in front of the top transformer chooses between putting a 600R load across the output or not. This info is available in the old 525 build thread, but no-one's explicitly mentioned it here I think.

- Bridge the pads by the meter IC for bar mode. Leave it unbridged for dot.

- The attack mod makes everything good there.

- I used the resistor values mentioned by someone earlier in this thread and the meter works great, FYI.

Anyway, there you go. Haven't used them a lot yet, but doing some rock vocals through one worked instantly, so I'm pretty impressed with them. Also, Pete's metalwork is the best fitting around here FWIW...

Oh, and now a pic:

Kaz
 

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Trying to finish up two of these, but all the links are dead...

Does someone still have the documents for this build (BOMs, overlays, schematics)? Would be much appreciated!!
 
tzman said:
Trying to finish up two of these, but all the links are dead...

Does someone still have the documents for this build (BOMs, overlays, schematics)? Would be much appreciated!!

PM'ed
 
Has anybody tried an InterFET VCR2N from Mouser? Are they any good?

http://www.mouser.com/ProductDetail/InterFET/VCR2N/?qs=sGAEpiMZZMv4z0HnGdrLjo0W1AxRZQdlOmKMZtW5%2fq6nKICE28TN7g%3d%3d
 
Ilya said:
Has anybody tried an InterFET VCR2N from Mouser? Are they any good?

http://www.mouser.com/ProductDetail/InterFET/VCR2N/?qs=sGAEpiMZZMv4z0HnGdrLjo0W1AxRZQdlOmKMZtW5%2fq6nKICE28TN7g%3d%3d

those look very similar, if not the same, to the ones i used.  I may even have a few left... I would have to dig them up.
 
I'm quite suspicious because their datasheet is very short. No graphs or other detailed information, just basic specs. Inquired on their site, will see what they tell me...
 
taliska said:
- The input and output pots require their cw / ccw swapping when being wired up. It was mentioned by one person and one person only earlier in this thread, so I didn't do it when I wired my first unit. Once I tried using it, it was indeed counter-intuitive, so I swapped them on my second one and had to go back and redo my first which was a bit of a pain (actually broke a pot, but luckily had a spare), so you can save yourself some work by doing it right the first time. I've never used the original units, so don't know whether that's a quirk of the original units or not.

I do have an original 525.  The "IN" pot is really a threshold control,  not input gain like an 1176.    IN is actually side chain IN,  so raising it lowers the output signal by adding compression.  It does seem backwards when first using a 525,  but that is how they behave.
 

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