Salas hotrodded blue DCB1 build

ahh right, that one isnt on the OMRON signal relay page. maybe nos or not a signal relay. OK i'll shoot Banzai an email and see what they say. I have a feeling the shipping will be insane, but yeah i'm sure I can find some other stuff that I want there.

Shipping was 9 euros to the USA. Don't know how much it is to countries down under ;) That's pretty reasonable from where I come from. So I bought a whole bunch of other stuff from them as well, i.e. non critical resistors, WiMA caps.

Anand.
 
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I have a question/suggestion concerning the grounding-scheme. Please see the attached picture. Normally the buffer's ground would be connected to the PSU's ground via the green jumper. If done like that, the buffer's return-current would share the shunt-reg's return-current path. In a power amplifier this can lead to problems when there are large current pulses from the PSU. Here we have a regulator with a constant current draw and a tiny buffer...but still, wouldn't it be better (lower impedance) to route the ground like depicted with the red jumper?
 

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The printed ''tail'' lets the filter caps currents recombine locally. Then you add yet another parallel tail only for the audio. I would not expect it to change anything. It ain't buzzing even on Tea's Lowthers as he reported with his proto, so...
 
Would anybody see any reason not to use a Mundorf Silver oil in the .22uF position? Other then the size issue obviously.

On a side note I did get a quote from Texas Components on the TX2575 and TX2352 resistors that DVB is using.

TX2352 220K00 *0.1%
1-99pcs $36.00 ea USD
100pcs $34.00 ea
250pcs $32.00 ea

TX2575 220R00 0.1%
1-99pcs $12.00 ea
100pcs $10.00ea
250pcs $9.50 ea

Plus shipping and such.

Is anyone considering starting a groupbuy for these items in the future?

I was also looking at doing Caddock TF0's in the 220K position instead of the TX2352's.
Any thoughts?
 
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I was also looking at doing Caddock TF0's in the 220K position instead of the TX2352's.
Any thoughts?

That's what I use, and an MK-132V in 1M position, like dvb.
I think the money is best spent on the 220R position myself, being in direct signal path.
It is most influenced in the signal path, and resistor swapping in general here WILL yield results in sonic character.
To me, the Z foils are worth it.
I paid about $10.00 each for mine for 4 qty.
I am planning to put some in an F5 signal path to see what happens...
 
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The final combination of parts could end up individual to the set, we can not foretell what suits best in a total. Silver oil could be too open in a ''fast'' parts neighborhood for instance. I would check out some parts after break in. There is always a higher ''high''.
 
lol, could not agree more. I will start with the wima and move on from there. I have always been partial to Mundorf so that is why I naturally started in that direction. I also took part in DVB's group buy on the 4700uF PS caps.

Here's another opinion to further obfuscate the issue:D

:eek:There are better places in a circuit to use the lauded 0.22uf Mundorf SIO as opposed to a bypass cap in an LED chain! Besides, when you look at the size of the cap and the space you have on the board...it starts making even less sense. Save that cap for another project!

I've started and most likely will stop with the WIMA in that position. The critical parts are the resistors and Jfet in the buffer circuit, the PS caps (4700uf), the attenuator and I/O section (RCA's or XLR's in my case). Salas has done all the work with the shunt regulated PS so that's nice. I'm using TX2575 for the 220 ohm resistors (matched to 1%), Caddock TF020's for the 220K resistors and either Caddock TF020's or Caddock MK132's for the 1 megaohm resistor. Again, I am building a differential version so matching of the key components in the buffer circuit can make a difference.

Anand.
 
Here's another opinion to further obfuscate the issue:D

:eek:There are better places in a circuit to use the lauded 0.22uf Mundorf SIO as opposed to a bypass cap in an LED chain! Besides, when you look at the size of the cap and the space you have on the board...it starts making even less sense. Save that cap for another project!

I've started and most likely will stop with the WIMA in that position. The critical parts are the resistors and Jfet in the buffer circuit, the PS caps (4700uf), the attenuator and I/O section (RCA's or XLR's in my case). Salas has done all the work with the shunt regulated PS so that's nice. I'm using TX2575 for the 220 ohm resistors (matched to 1%), Caddock TF020's for the 220K resistors and either Caddock TF020's or Caddock MK132's for the 1 megaohm resistor. Again, I am building a differential version so matching of the key components in the buffer circuit can make a difference.

Anand.

Good advice.

Thank you sir.

Exact direction I have decided on.