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BTSB Buffer - SE/Bal to SE/Bal Buffer GB

Ine,
I noticed you did not install the BTSB onboard DC/DC converter and are feeding the board +/-15VDC directly. But J10 is also connected, Why?
Just to get some light in the green LED. Like to have some indication the the pcb have power. (well only one phase, that is).
The BTSB is OUT of my pre-amp. Testing another gain (+6dB stage.) Will be measured in the beginning of next week :) . Pictures/info of this gain stage have been posted here.
Opamp's is OPA1656
J.R
 
XRK,

Are you planning to put any more of the non-panel mount BTSBs back in your store? The panel mount BTSB works well as an input board to and amp or preamp. It can't be used as an outlet buffer to take a single ended signal and convert it to balanced due to the mounting.
 
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Joined 2012
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Thank you for your order.

You ordered the BTSB Panel Mount and the latest version is Rev1.2p. The BOM for the panel mount is quite different than the non Panel Mount. Let me get you the BOM. Please PM me your email.

Here is the schematic and you can see that the DCDC converter is different and the balanced output driver is OPA1637.

I found the BOM - it is here:
https://www.diyaudio.com/community/...e-bal-to-se-bal-buffer-gb.358142/post-6522803

1664298247138.jpeg
 
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Thank you for your order.

You ordered the BTSB Panel Mount and the latest version is Rev1.2p. The BOM for the panel mount is quite different than the non Panel Mount. Let me get you the BOM. Please PM me your email.

Here is the schematic and you can see that the DCDC converter is different and the balanced output driver is OPA1637.

I found the BOM - it is here:
https://www.diyaudio.com/community/...e-bal-to-se-bal-buffer-gb.358142/post-6522803

View attachment 1094730
Can i substitute all the OPA1656 with other dual op amp, for eg. LME48960 which i have on hand without any changes to other parts of the circuit?
 
Thank you for your order.

You ordered the BTSB Panel Mount and the latest version is Rev1.2p. The BOM for the panel mount is quite different than the non Panel Mount. Let me get you the BOM. Please PM me your email.

Yes, this is the same panel-mount BTSB I had ordered, I don't know, maybe a year ago. So, the BoM is unchanged. Awesome. I was wondering whether a v1.3 or v1.4 has come out.
 
If you change the feedback resistors R33, R34, R35, R36 from 4K99 to 2K49 it will reduce all the gain settings by 6dB. I think that's what you are asking about.

So the new gains will then be: -6dB, 0 dB, 8dB and 14 dB ? Yes? And R17-R32 stay as the stock values as referenced in the schematic?

Best,
Anand.
 
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yes. The generalized gain expression is Rf/Ri, where Ri consists of various combinations of resistors in parallel. In the original design with no switches closed that value would be 4K99/4K99, or 0dB. If you cut the value of Rf in half it becomes a gain of -6dB, which is what you asked for.
 
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yes. The generalized gain expression is Rf/Ri, where Ri consists of various combinations of resistors in parallel. In the original design with no switches closed that value would be 4K99/4K99, or 0dB. If you cut the value of Rf in half it becomes a gain of -6dB, which is what you asked for.
This is fantastic! Now a whole host of amplifiers can be used. I say this because a few of X's inspired designs are 28-29dB gain and that can be too much in many systems. This BTSB IS the 'best thing since sliced bread'!

Best,
Anand.
 
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