CAPI-Gear; New CA-0252 (2520 Type) Opamp Kits and DIY Parts Galore!!!

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jsteiger said:
Tubemooley said:
I got all blue dots from Scott. But he told me how to turn the blue into the red. It's like two SMT caps I think. I prefer clean blue over vintage red. DW.
I actually got one of Scott's vintage red dots coming tomorrow in the post. I'm anxious to check it out in my new pre. We got a few to check out side by side. Some Huntingtons, Avedis 1122, SL-2520 red and a custom proto built by one of our fellow lab buddies.  :)

Let me know what you find.  I have been super happy with Scott's OP Amps.  I would love to hear your findings.
 
dandeurloo said:
Let me know what you find.  I have been super happy with Scott's OP Amps.  I would love to hear your findings.
Dan,
We had some good findings in our little shoot out test. I took a vintage Huntington with for the main use  in my pre. There were a few different variables besides just the DOA's though. My friends desk has Datatronix labeled 2520's, JE 110k input transformers and 2623-1 outs. His BAE racked 312's have Huntingtons, JE 110k's and vintage 2503's. All were very close and clear to tell they are in the same family.

Anyhow, after comparing the above pre's only, we swapped DOA's in my pre and continued with listening, using the Huntington as a benchmark. The DIY version of one of our lab members here was so close to the Huntington it was scary. It's a proto unit that was sent to me to evaluate. I won't mention who's work it is unless they want me too. There may be more to that soon. Anyhow, the SL-2520 red dot was the next closest to the Huntington. Scott's amp actually made the top a slight bit more "open" sounding in a very nice way. His DOA was a very nice mate to my pre overall. The midrange appears a little more tight and focused as compared to the 312. Maybe a bit more "colored" sounding. We also plugged a 990c in there from John. It was fine but too clean for me and nothing like the rest of the amps. Exactly as one would expect. The 1122 was the other we tested. That amp appeared darker sounding than the Huntington and the others(except the 990).

So, I can say that the sockets are a must have for any project like this. My friend Dave was enamored by them. He has never seen them before.

I guess these are merely my opinions and we all know what opinions are like...

BTW, Dan, I clicked over to your site. You guys make some unbelievable drums man! Just beautiful. I was checking out some of the youtube videos. That PIllar Drum Solo, even though it's short, is sick! What a monster! Some great tone you guys have going on there.  8)

Cheers, Jeff
 
Yo - This is friggin' killer. It's very time-consuming to do tests like this. Yes, these are your opinions. But if I read your opinions and try to remain objective, I can get good information from that. Audio quarrity (the take-out Chinese food variety) is a subjective thing. When you say things like this DOA is just a bit blank, blank, blank..... compared this other DOA, that means something to me. We have to break down our qualifications into smaller pieces. The eskimoes have a hundred different words for snow. Well, we all have a hundred different words (or short phrases) for describing audio. I believe the Hardy 990c is cleaner due to the LM394 matched pair on the input. That's my opinion. If I need that clean-ness for something, I use a JH 990c. The real task here (as I see it), is to match up these subjective qualifications with the scientific real-world component differences in these DOA's. Then, when I want this sound, I reach for this DOA...... Anyways, you guys get the idea. I'm definitely interested in this new DOA proto. Please keep us informed on that if you can. DOA's, DOA's, DOA's...... I'm a very sick man. DW.
 
Tubemooley said:
...I'm definitely interested in this new DOA proto. Please keep us informed on that if you can. DOA's, DOA's, DOA's...... I'm a very sick man. DW.
Yes Dana, you are sick. I have 3 words of advice for you. Medicate, medicate and medicate.  8)

So, I have received some awesome news on 2 fronts.

First, I will soon be carrying Scott Liebers' SL-2520 versions on my site. These will be for optional purchase with my mic pre kits. We will have both the red dot and blue versions available. These are great sounding amps and priced very well compared to the rest of the pre-built and tested 2520 style market these days. I will not have them for sale on an individual basis, only within a kit. They can still be purchased on an individual basis from Scott's site. These will be more for someone who isn't up to stuffing their own, for whatever reasons.

Secondly, it looks like the newest DIY 2520 kit version will be coming to my site as well.  :D This is a very exciting thing for me. It will really help round out my API dedicated web store. I have posted here and there about my listening trials with a fellow Lab member's home-brew version. I say "home-brew" but they are actually very elegant, 2 sided boards from a PCB manufacturing house. This work had be "cleared" before we could proceed as the reverse engineering has been completed by someone else from the Lab. That looks to be all good. So, the boards are from our own gar381. Gary has really done an outstanding job with his Eagle layout and his component selection. The reverse engineering for this DOA, and most every other 2520 DOA version floating around, all stems from Peter Purpose. This was quite an interesting point that Gary and I learned during our email and phone discussions. Gary's original goal, was nothing more than to "see if he could do it" for his in his own personal projects. He was pleased with his results and sent one to me. I told him it wouldn't be right to not make his fine work available for the DIY community. So, there you have it. We are determining if they will be boards only with BOM or in full, all parts kit form. This is really Gary's baby, I am merrily the conduit.  ;)

These will only be available in kit form, no pre-assembled versions. Pricing is yet to be determined but will be very reasonable, this I can assure you.

So, It looks like the birth of the gar2520 is official! Congrats and thanks Gary... and of course thanks Peter for your hard all of those years ago.

Cheers, Jeff
 
Someone mentioned Pillar??
Thats my favorite band!!!
Dandeurloo? you the guy from Risen Drums?? wow...

Jeff talking about discrete op amps...i should mention to you that John Burdick (Burdij) makes some nice 2520 clones...they look a lot like Scott's ones but John sells them 25$ a kit..... ;D

A client of mine tested 990s in a 312 preamp vs 2520 and liked better the 990 why? the 2520 were using a input transformer in a 1:5 Ratio...
So my final conclusion was that every Discrete Op amp reacts different to every ratios..
 
3nity said:
Dandeurloo? you the guy from Risen Drums?? wow...
Check out their site. I am not a drummer but really would like to become one after checking out their stuff. Just gorgeous work. The hardware is just killer.
A client of mine tested 990s in a 312 preamp vs 2520 and liked better the 990 why? the 2520 were using a input transformer in a 1:5 Ratio...
So my final conclusion was that every Discrete Op amp reacts different to every ratios..
I couldn't agree more. I know you will hear different things with a 1:10 also. Plus, I guess it depends on your end goal. My goal was to replicate the overall "sound" of my console pre's. This is no job for the 990c!

Cheers, Jeff
 
Hey guys, check this out.

It's the official unveiling of the gar2520 DOA. This is a classic design, 9 transistor, 2520 style discrete op amp. The unit pictured here is one of Gary's prototypes. Gary has built a handful of these to carefully test his board layout, component selection and overall circuit. So, the guess work is over. The leg work has been done.



This DOA is based on the vintage Huntington 2520, originally reverse engineering completed by Peter Purpose many moons ago.

These raw DIY boards will be offered on my site soon. Full parts kits will probably also be put together. Cost is yet to be determined but will be very reasonable no doubt.

Jeff
 
Great news that you are soon to be carrying kit DOAs in your lineup.

I'll certainly be taking a bunch!
 
alexc said:
Great news that you are soon to be carrying kit DOAs in your lineup.

I'll certainly be taking a bunch!
Yes, I agree and thanks. What in the world would an API dedicated web store be without a killer DOA kit!

Jeff
 
Tubemooley said:
Eedley. Oodley. Doodley. Please get the boards. Get the kits if you can. Good stuff. I will want 10 pieces minimum. DW.
In the works Dana. Remember...medicate... ::)

Anyhoo, I got the new GroupDIY face-plates in today! Looking might cool. Turned out sweet.

Here's a taster.


Here's a link to them on the site.

So, what to do you think Volker?? Did I do you proud?

Cheers, Jeff
 
Just ordered 2 ....  only 17 left now

Folks better jump on this! What a great fast easy project to get some 312s!!
For this price why DIY one ?

Although I must admit I feel a little dirty for buying a full "kit"  ;D  "hey which way does this resistor go? "

Thanks!!

-Chuck
 
ChuckD said:
Folks better jump on this! What a great fast easy project to get some 312s!!
For this price why DIY one ?

Hey Chuck,

You probably know this but for those that don't this is not the 312 circuit.  Jeff points out some differences on his site here

http://classicapi.com/catalog/product_info.php?cPath=22_47_55_57_64&products_id=96

I was just figuring out my order!  I already have a selection of original iron so I'm just buying the other bits and pieces.  I need to get an API rack to tide me over until the 51x rack is finished.

Cheers,
Ruairi
 
For those who don't know yet, I have received the first shipment of Ed's EA2622 transformers!!! So, most of the kits and bundles are now available.

I've had a good run on the kits, 2503's and the 2622's over the last day and a half. Currently there are 11 input transformers left. I will have more in around the end of next week.

I also will be ordering more raw face-plates on Monday. Those should also be in by the end of next week.

I would like to thank all of my registered customers for just hammering me with orders!  ;) :eek: 8) I just can't believe the fantastic support you guys have given me and the site so far!

I have nearly all orders packaged and ready to ship. Some have been shipped already and the balance will be dropped at the local Post Office tomorrow. I will update your order on the admin side of the site, which will generate a "shipped" email notification.

I am anxious for some feedback when you get around to it. I quite confident everyone will be pleased!

Cheers, Jeff
 
anyone know where to get a cheap lunchbox type case? I think these kits might be too good of a deal to pass up..
 
Svart said:
anyone know where to get a cheap lunchbox type case? I think these kits might be too good of a deal to pass up..
Volker and Sahib are working on this now.  8) The thread in the Lab is here. Things start to really develop around page 7 or 8.

This will be probably the biggest, coolest project to hit the forum in a long time. Here is the detail page describing the GroupDIY 51X Alliance and advantages.

best, Jeff
 
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