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

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Tungstengruvsten said:
Hey Jeff;

Any sort of rough ETA on the power supplies for 51x racks?  I really want to order a second rack/PS but the PS has been unavailable for awhile now...

Thanks!
I have everything here. I just need to get the hardware kitted up so they are ready for immediate shipment. I plan to have that done over the next few days. I've been swamped the last few weeks.

BTW, this is a Sears poncho  ;D
 
The Floor Box PSU kits are now marked in stock at the store. You can find them right past her fuming incense stencher, where she hung her castanets.

http://classicapi.com/catalog/index.php?cPath=176_178
 
I have received the new 508 Rev B backplanes and added them to the store stock. The main dif from the previous Rev is no more shield option for the input. All shields connect to the Chassis ground plane. DC-Link options are now handled by a small slide E-Switch. http://classicapi.com/catalog/product_info.php?cPath=137_138&products_id=240
 
In light of the upcoming FC526 Compressor kit release, John Kennedy from realgearonline.com and I have have decided to give one full kit away! The rules are very simple but please read them to make sure you are eligible.

Details can be found here http://www.realgearonline.com/board/13/capi-giveaway

Good luck to all!

FYI, the production kits should be up at the store within the next 2 weeks or so. The last of the parts are trickling in now  ;)

Cheers, Jeff
 
I've just added a few new things to the store.

First up is a Litz wire version of the 2503!
http://classicapi.com/catalog/product_info.php?products_id=437
Litz-2503.jpg


Next is a 2-Stage utility line amp card based on my vintage API console
http://classicapi.com/catalog/product_info.php?products_id=438
2-Stage-Line-Amp-final.jpg


Happy Sunday!!  :)
 
So the 2s-la could be used as a simple line level booster? But I would need the 2ch aca & booster for a full console channel (minus eq/pre) ? Still got some reading up to do but trying to wrap my head around these pcb`s, including the 4 channel aca (which is used for summing of the channels afaik)
 
The 2S-LA card is the complete input channel minus the EQ, fader, 1st stage output tranny and pan network.

The 2-ACA-Bo would be used to actively combine numerous input channels so only one is required for a 2-mix out. You could use these for subgroups if you wanted/needed that feature.

The 4 channel INV-ACA's would only be used if you wanted to bucket or pre-sum the input channels before hitting the 2-ACA-Bo card.
 
Very Cool! I'm assuming that this line input could also be used to drive a few echo sends out of the 2nd stage? I'm thinking about doing a summing box with the 2 ACA-BO, but I keep coming back to wanting a couple aux.'s. Also, do you have a schematic for the pan network around? Maybe I could work this into more of small format line mixer desk instead of just a summing box, kinda like the SSL X-Desk but all API and sans the monitor section?
 
drumminkiger said:
Very Cool! I'm assuming that this line input could also be used to drive a few echo sends out of the 2nd stage? I'm thinking about doing a summing box with the 2 ACA-BO, but I keep coming back to wanting a couple aux.'s. Also, do you have a schematic for the pan network around? Maybe I could work this into more of small format line mixer desk instead of just a summing box, kinda like the SSL X-Desk but all API and sans the monitor section?
Something like this is all you need for panning.
 

Attachments

  • Passive-pan-pot-network.pdf
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So... is the 2s-la basically a missing link without the filters?

Say I would build a small 4 channel mixer, would this be a feasable setup:

One 2s-la per mono channel (4 in total), each going into 4 ACA summer (bus), then the aca into the 2-aca/bo for master bus?

Just an example to try to wrap my head around this.

What would be the benefit of using the 2s-la as input stage instead of going straight into an eq and from there into the ACA`s, except the extra gain-stage? And you would need an output tx for balancing going from stage 1 of the 2s-la out to the "insert point", and then an input tx for debalancing before into stage 2?

Also, from looking at this schematic:
http://www.classicapi.com/catalog/images/gallery/PCBs/inverting_ACA/Block-diagram.pdf

I can only see 4 channels going into each ACA channel, instead of the 8 it is marked at on the top? Are 2 channels being passively mixed before going into each ACA?

Sorry for my noob questions. Would be awesome to see some visual examples of the use of these units :)


 
fragletrollet said:
So... is the 2s-la basically a missing link without the filters?
Besides the output trafo's and discrete voltage followers, yes.

Say I would build a small 4 channel mixer, would this be a feasable setup:

One 2s-la per mono channel (4 in total), each going into 4 ACA summer (bus), then the aca into the 2-aca/bo for master bus?
The 4 channel INV ACA is not a necessity unless you are summing 48 or more channels.

What would be the benefit of using the 2s-la as input stage instead of going straight into an eq and from there into the ACA`s, except the extra gain-stage? And you would need an output tx for balancing going from stage 1 of the 2s-la out to the "insert point", and then an input tx for debalancing before into stage 2?
The input x-fo is not really needed especially if being fed from a x-fo balanced device.

Also, from looking at this schematic:
http://www.classicapi.com/catalog/images/gallery/PCBs/inverting_ACA/Block-diagram.pdf

I can only see 4 channels going into each ACA channel, instead of the 8 it is marked at on the top? Are 2 channels being passively mixed before going into each ACA?
It is drawn this way due to space and to not over complicate the drawing. Kinda normal fare for things like this.
 
So how would you physically sum the ouputs from the 2s-la`s to the 2aca/bo if using more than 2 channels? It only has 2 inputs (on the aca side, which is the side I presume to use?).

Edit: via a passive resistive network I`m guessing?
 
fragletrollet said:
So how would you physically sum the ouputs from the 2s-la`s to the 2aca/bo if using more than 2 channels? It only has 2 inputs (on the aca side, which is the side I presume to use?).

Edit: via a passive resistive network I`m guessing?
The output of each device (2S-LA) would go thru a 47k bus R and then into the 2-ACA-Bo's input.
 
Sorry for my noobieness, but what is the difference between a "normal" resistor and a bus resistor? Would any 47k do?

And what kind of terminal is good for the amounts of cable that can be summed with the 2aca/bo? I mean, if it can handle up to 40 channels..
 
fragletrollet said:
Sorry for my noobieness, but what is the difference between a "normal" resistor and a bus resistor? Would any 47k do?
None. The function of this R is for the mix bus, hence the term bus resistor.
 
So in a 2s-la build, which 2520 position would have the most audible effect on the sound? The booster (second) stage? I`m thinking about making a "hybrid" mixer, and since it would need so many opamps, it would be nice to know where I could prioritize on the opa`s that aren`t diy and more expensive.
 
It would take a little trial an error to find out the best opamp combo for your needs. If you were gonna do an IC & DOA combo I would start with the IC in the receiver spot and go discrete in the fader booster.
 

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