calling all the api cloners.. group buy ??

FWIW, the Cinemag 1:10 units cost $33.50 each for quantity up to 49. 50-99 it is $31.91 each.

That's quite a bit better than Jensen or Bauer, and I'm guessing it'll be equal quality.

I'm waiting for a quote for Cinemag's 1:8 unit as well and will report when I hear back.

JC

I'm thinking about the different outputs of microphones and how this relates to the choice of input transformers. In the case where someone is building just one or two of these for all around use, getting the exact replica of the original iron is ideal. In my case I'm building 10 of these preamps in a 4u rack so I can see setting up different preamps with mic input trannys that match up different output levels of mics with the sweet spot power band of the opamp. For instance, maybe the 1:10 tranny is what is needed to present the right signal level to the 2520 opamp to get that "growl" spoken of earlier, when using weaker ribbon microphones. OTOH, correct me if I'm wrong but aren't those transformerless mics like the Neumann TLM-103 putting out an unusually strong signal? Maybe for a TLM-103 it would be good to use something like 1:6 to put it in the same rang of the opamp.
Does this sound like a good thing to do? Or should I just stay away from the brown acid?
Kelley

well.. personally i've decided to stop the group order till we will know more about the chance to do some 2622 replicas..
i've started to dig around to find one to donate to the butcher :wink:
let's see what will happen in the next days.. i'll keep everyone informed.
:thumb:

I think Dan Alexander would be able to sell us one. Maybe if we could split the costs with those interested, it would not be expensive.

Dan Alexander don't have any.. already asked him
:sad:

I say we all get together and buy Seth and his wife and family some beer, flowers and jewelry...

Keith

Better idea..
Seth, if you want, here is my idea..
you send CJ your 2622 that will be analyzed carefully to reproduce exact replicas and we (as group order) will give you a pair of the replicas for free in exchange. so that we (group) will split the cost of the operation.
what do you think seth?
and.. what do you think people? could we do this? it's just an idea.. who wants to join?

If its OK with Seth I am in.

Hi guys,

I'm OK with that. Let me just double-check the BTI pin arrangement against an API one and make sure they're the same. Yep, they're the same, and the BTI schematic specifies an AP2622, so it's the genuine article. The only thing I noticed is that the pin pattern is not the same as the 312 board I scanned. The 2622 is a circular pattern and the 312-3 board I scanned is two parallel rows of pins more widely spaced. Check out the jpg below. If we order the new 2622s with the original pattern will someone be able to alter my scan to make it fit? Should we order tham with leads so they're easier to adapt to different uses? My board must be a later one made for Jensens or something, I guess. BTW, my BTI schematics call for an AP2622, but the mfr.'s part number listed on the bill of materials is "BK-K47B". Could that be a clue to who made the transformer? Does that look familiar to anyone?

Also who am I sending the trafo to? CJ?

Also, I meant to add - you guys don't have to get me an extra. I'm happy to contribute and I'll be in on the group buy anyway.

So far I'm having to come up with several footprints for my PCB for the different trannys I've already got. Would it be possible to select the most likely second choice to make the footprint of this cloned 2622 like it so we can leverage an existing footprint?
Kelley

I don't actually know what's possible. The 2622 is .96" in diameter with the 6 pins as on that diagram. Jensens and Reichenbachs , which are the default standard, I guess (?), are 1.13" in diameter with 8 pins in two rows, .75" apart. The board I scanned was made for 6 pins in two rows roughly .75" apart. I don't know if there's some intrinsic functional reason for the 2622's different footprint or if the footprint can be changed. Anybody?

I hope there's no magnetic voodoo about the shape that would change the tone if it were pinned out like a Cinemag, which is a tighter footprint than the Jensen. But I guess if it has to be a new footprint, so be it, we got ta do what we got ta do.

Seth..
damn.. you are too generous!!!
i still think that you deserve some payback.. at least one of the replicas will be free for you.. at least!!! damn!
About who will be the faithfull buthcer, well.. juts one answer, CJ :green:
So, please CJ, if you are willing to help us, jump in and say the word
about the pins.. i think the best way is to get a pcb mount version, so, circular as the original seems the best.. why? cause this way the path from the input till the doa will be as short as possible, and leads tends to break. there will be surely the chance to solder some leads to the pins i think.
Thank you very much Seth for the offer.. let's hope for the best now!!
:thumb:

Hi Kruz,

I spoke to CJ. He felt that we should hold off dissecting until we can find a spare 2622 that isn't actually in a mic pre. So we should keep looking and see how it goes. If we absolutely can't come up with one we'll think about it again. I've been asking around, so we'll see if anyone responds.

excellent Seth.. i agree

I´ve seen a pair of them at ebay once. WHY didn´t I bought it? HELL!

Ya know...... I saw an ebay auction once (about two years ago) that had TWENTY-SIX (26) of the 2622's, and the winning bid was around $150. I had considered bidding, but passed.

Ouch!!!

JC

Oof! The one that got away.