A12 FAQ

[tele_player]

Good - once the BOM is online, I'll order the parts. Have you settled on transformers and recommended sources?

[tpryan]

The BOM is up, as are the final schematics. The full kit will come with CineMag CMMI8-PCA and Profile Electronics 4804 transformers. Hybrid op-amp kits will be available separately. Minimal kits will be $79, full kits $259. Assembly photos are up, but instructions are still in progress.

[wtn]

Good - once the BOM is online, I'll order the parts. Have you settled on transformers and recommended sources?

FYI - Here is where I got my parts for the Minimum Kit:

Avedis 1122 op amp - Bought direct from Avedis Kifedjian - makes
the 1122 for Brent Averill's 312's. Very nice fellow. Call him at
818 784-2046 (Averill Enterprises) or email avesdisk@comcast.net

Lundahl LL1578XL input trannys - Kevin at www.kandkaudio.com -
best to call him. I had trouble getting email to him and according to him
I was not alone. (wife when they arrived - "You paid $140 for these little
things")

I will use original API 2503 output trannys - kind of had these for a while.

All the rest will come from digikey and mouser - with the PS02 and A12
min kits from Tim.

Hey Tim - it appears that the full kit ($259) comes with an Avedis 1122
op amp - is that correct? If so, that's a heck of a deal.

(me to wife: "Do you know how much two channels of this stuff would cost
if I went out and bought it new?")

William Nordin

[tele_player]

I'll just order a full kit when Tim's got one ready to go. On my J99's, I found it tedious ordering from DigiKey, Jensen, K&K, Hardy... I'll let Tim put up with that

Willian - do you already have the A12 board? Darn, I wanted to be one of the first!

[wtn]

I'll just order a full kit when Tim's got one ready to go. On my J99's, I found it tedious ordering from DigiKey, Jensen, K&K, Hardy... I'll let Tim put up with that

Willian - do you already have the A12 board? Darn, I wanted to be one of the first!

Tim is waiting for the Grayhill rotary switches - the make before break or shorting version. I was able to locate a couple of them and Tim said he would sell me a couple of the prototype boards along with the xlr jacks. I found the Grayhills at Allied. They had 10 - now 8 last I looked. If you want to go this route check with Tim beforehand. The A12 cards should be here Friday. I have been waiting for these since January.

[davidkakon]

hi everyone:

i received my a12 preamps from tim and they sound great. they sound exactly like apis should, strong low mid range and lots of energy and punch.

one thing:

i notice the gain is not as hot as an original 312 api (though this should be a good thing seeing as how the 312 is usually too hot on everything) but here it seems a little too low. where the n72 needs a setting of 6 the a12 needs an 8 (both outputs max). on a female vocal with a 57 i needed to put the a12 at max!

any tips?

I have to say that Tim is a really great peson to deal with and he makes a beautiful product. the n72 sounds especially terrific. thanks Tim!

david

[wtn]

hi everyone:

i received my a12 preamps from tim and they sound great. they sound exactly like apis should, strong low mid range and lots of energy and punch.

one thing:

i notice the gain is not as hot as an original 312 api (though this should be a good thing seeing as how the 312 is usually too hot on everything) but here it seems a little too low. where the n72 needs a setting of 6 the a12 needs an 8 (both outputs max). on a female vocal with a 57 i needed to put the a12 at max!

any tips?

I have to say that Tim is a really great peson to deal with and he makes a beautiful product. the n72 sounds especially terrific. thanks Tim!

david

Hello,

Would you care to explain? As far as I know the full kits are not ready
yet. Yes I have a couple of the first A12 cards, but I am using the
Lundahl Input transformers, API output x-formers, and the Avedis
1122 op amps. So what components are you using? And I have not
built mine yet - still waiting for parts from digi-key.

[davidkakon]

explain what? I ordered a unit from Tim with 2 n72s and 2 a12s. It got here last week and it sounds terrific. The only thing with the A12 is the lowish gain (*Tim said he can easily adjust the gain to match that of the n72, the a12 needs 2 extra clicks to match the n72) and also the pop I get when I switch the gain pot, but Tim also has a remedy for this. mine has the brent averill opamps.

I prefer the n72 so Im ordering 2 more and will eventually put a pair J99's in the last 2 slots. The n72s are more open and more extended than the A12s, however the A12's fill the low mids very well and the forwardness is a great compliment to the softer n72.

David

[RalphE]

I just want to order the a12...i plan on using the averill opamp too. Where are they?! Heh...no rush but man oh man i want it. Can I just pay now so I get in on the next batch? This message board seems like a wasteland compared to what seventh circle audio offers...and I want to get my stuff before everyone else goes crazy and I can't get anything. seventh circle are purely genius...this is TapeOp fantasyland.

[wtn]

explain what? I ordered a unit from Tim with 2 n72s and 2 a12s. It got here last week and it sounds terrific. The only thing with the A12 is the lowish gain (*Tim said he can easily adjust the gain to match that of the n72, the a12 needs 2 extra clicks to match the n72) and also the pop I get when I switch the gain pot, but Tim also has a remedy for this. mine has the brent averill opamps.

I prefer the n72 so Im ordering 2 more and will eventually put a pair J99's in the last 2 slots. The n72s are more open and more extended than the A12s, however the A12's fill the low mids very well and the forwardness is a great compliment to the softer n72.

David

Well you must be a VIP since the A12's are not available to the common folk yet. What input/output transformer does your A12 have? So how
would you like two A12's and two N72's because that's what I have in
mind eventually.

[tpryan]

David got a few of the first ten A12s as part of a custom order. They have CineMag CMMI-8-PCA input transformers and Profile Electronics 4804 output transformers. They're set up for 60dB max gain, and don't have the preferred rotary switches. In light of feedback we've received from David and other early users, in addition to our own testing, the complete kits will have resistor values that give 70dB max gain, like the N72. The revised BOM is already up.

A12 minimal kits are just days away, really!

[wtn]

David got a few of the first ten A12s as part of a custom order. They have CineMag CMMI-8-PCA input transformers and Profile Electronics 4804 output transformers. They're set up for 60dB max gain, and don't have the preferred rotary switches. In light of feedback we've received from David and other early users, in addition to our own testing, the complete kits will have resistor values that give 70dB max gain, like the N72. The revised BOM is already up.

A12 minimal kits are just days away, really!

Thanks for the heads up Tim. Luckily, I have not started on the A12
boards yet. Well, off to Mouser for more resistors. Yea it sounded like
David did not have the "shorting" version of the Grayhill switch - sure
hate to have to un-solder one of those and replace it.

[davidkakon]

not VIP, just good timing. I think I caught Tim on the phone at the right tme when I ordered mine.

I really like the 2 preamps (N72, A12). ideally i would get:

4x N72
2x A12
2x J99

best
david

[The Landlord is Dead]

Any updates on when the A12 will be available to the rest of us?

[tpryan]

A12 minimal kits have been available for a few weeks, but we haven't had a chance to update the web site. Full kits will be available very soon, we're still waiting for a few odds and ends. Minimal kits are $79, full kits are $259, plus tax and shipping. Send an e-mail directly to sales@seventhcircleaudio if you'd like to place an order.