API 525 compressor

[peter purpose]

Easy now boys... tis only a bit of fibre glass with some thingies stuck to it.

I'm aiming to have this up and running by the weekend, so hopefully I can verify the pcb and get it off to fab.

peter

 

[thenovice]

[quote author="peter purpose"]Easy now boys... tis only a bit of fibre glass with some thingies stuck to it.

I'm aiming to have this up and running by the weekend, so hopefully I can verify the pcb and get it off to fab.

peter[/quote]

what do you think the est. price will be per board?
does the 525 depend on the 25.50 op-amp?
or could you swap in another? maybe the melcors?

 

[peter purpose]

<<what do you think the est. price will be per board?>>

There are 5 pcbs to my layout...
Mainboard
Vertcal op amp
Pot and meter board
2 switch boards

They will be double sided, plated through hole, masked, screened and have a gold plated edge connector. The outfit I use has quoted me around £16 GBP per set, so add a a couple of squid for postage and they'll be around that figure.

<<does the 525 depend on the 25.50 op-amp?
or could you swap in another? maybe the melcors?>>

Any 990 footprint amp should work in there, except maybe Fred's.

peter

 

[Guest]

[quote author="peter purpose"]
Any 990 footprint amp should work in there, except maybe Fred's.

peter[/quote]
lol! now only if you had 4 of them try out...

 

[peter purpose]

I wouldn't dare....

 

[Guest]

Excellent!!!

 

[barclaycon]

My 525 compressor only has 3 op amps. So what is the vertical sub-board?

 

[API]

Looks great!!
I want some of these boards to!

I also have a pair of original 525´s if there is something that you are wondering about.

Dennis

 

[Guest]

[quote author="barclaycon"]My 525 compressor only has 3 op amps. So what is the vertical sub-board?[/quote]
Peter stuck in a opamp for a balanced input (page 9 of the thread)

 

[kvintus]

looking great. Got to get me one of these...

/Anders

 

[antiguru]

posting just to register my excitement!

getting together some iron in anticipation =D

 

[thenovice]

yep i need one

 

[Handcrafted Tone]

quick question, is it standard to short the Agnd and GND pins in 500 series modules, or is there a better way?

Thanks Peter!

btw, I will be buying 1 or 2 modules soon.

 

[peter purpose]

[quote author="Handcrafted Tone"]quick question, is it standard to short the Agnd and GND pins in 500 series modules, or is there a better way?

Thanks Peter!

btw, I will be buying 1 or 2 modules soon.[/quote]

As far as I know they are all internally (on pcb) connected.

 

[Handcrafted Tone]

Thanks!

 

[Tubemooley]

Are the trannies used in these comp's the "standard" api 2503's and/or a cinemag equivalent? Are the semiconductors relatively easy to obtain? Can anyone post a BOM for these units? I've already ordered kits from peter. DW.

 

[tommypiper]

Yes, I've asked the same question of Peter about the transformers, as I have a Cinemag order ready to go in and would like to know what to add for the 525s.

They look like standard API thingies but let's hope to hear it from Peter shortly.

There's no iron on the input apparently?

 

[syn]

This is what Peter told me:

"AP2623 for originality. Sowter has a replacement. 9935

Both transformers are identical AP2623. You could try anything in there, but both need to be 1:2."

cheerz

 

[Tubemooley]

OK. Thanks Syn. That's good info. I'll get on my horse when I get a minute and go look at the cinemag's. I'm sure he has a 1:2. I guarantee that the Sowter's are good but I prefer the cinemag's or lundahl's. We'll figure out what's best and get them ordered up.

And yes, there is no trannie on the input. I am not an api expert but I've looked at hundreds of schematics (not just api). Apparently the standard 525 has an unbalanced input. Peter has added an opamp circuit on the front end to make that a balanced input. I believe he did this by adding another little board which holds one of his DOA's. HANG ON. I just looked at the "original" 525 schematic again. I call that a quasi-balanced input. The (+) phase of the input is connected to the non-inverting input of A1. But the (-) phase is connected directly to COM. This works fine but the input signal is not floating and could result in ground loop noise depending on the input source. DW.

 

[mich]

looking at the 2623 datasheet it looks like its just like the 2503 output transformer , only missing one winding.

so u can go only 1:1 or 1:2 (and with 2503 u can do also 1:3)

i also see that the 2623 has 4 types of the same model that only differ in mechanical size.

i wonder if a 2503 can fit peter's board?