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

[xrk971]

Mine are not either. I have to use flip up magnifier goggles for anything smaller than 1210. And a stereo microscope is a must for small stuff like 0402.

 

[Ine]

Done !

Regards
J.R

 

[Vunce]

Nicely done! Just checked over some of your resistor pads with some flux and touch up with an solder iron so there’s no cold joints.
SMD is not so daunting

I installed the same header and omitted the filter components on one of my BTSB’s to use a linear power supply.

 

[Ine]

Hi ,

Nicely done! Just checked over some of your resistor pads with some flux and touch up with an solder iron so there’s no cold joints.
SMD is not so daunting

Think they are all O.K

 

[xrk971]

Beautiful work, JR! Neat solder joints.
Only thing I would do different is to place the resistors label up so that you can debug the board visually if there was ever an issue. Leaving the filters for the PSU is a good thing even with an off board PSU. It will clean off any stray RFI.

Now have a listen and enjoy.

Can I ask what PSU you will be using and why you chose not to use the DCDC? I even gave you one as a bonus. They are simple and very low noise in the audio band as can be seen in the FFT noise floor that I measured and posted. Not all linear supplies (even fancy shunt regulated ones) can live up to -130dB noise floor at 50/60Hz.

 

[Ine]

Hi,
I will use this power-supply: ALD-HPULN PS

• 
  

• Details / Features​

  
  Dimensions: 101 x 51mm / 3.97 x 2.01"
  Input Voltage: max. <14VAC / <20VDC
  
  Height (without spacers): 52mm / 2.05"
  Output Voltage: Adjustable 0-<15VDC
  (Preadjusted to your desired output voltage)
  Output Current: max. 2,5A / rail
  
  Ultralow RMS Noise: 0.8µVRMS (10Hz to 100kHz) per regulator
  Further reduced noise by 5x LT3045 in parallel operation per rail
  Ultralow Spot Noise: 2nV/√Hz at 10kHz
  Ultrahigh PSRR: 2x76dB at 1MHz
  High Bandwidth: 1MHz
  
  High quality parts only
  Low ESR capacitors
  Low TC resistors
  Aluminium-Polymer capacitors (OS-CON, K750)
  Soldered with silver alloy

 

[xrk971]

Wow, nice PSU! Looks great then. 0.8uV rms is awesome.

 

[Ine]

Wow, nice PSU! Looks great then. 0.8uV rms is awesome.

Further reduced noise by 5x LT3045 in parallel operation per rail

 

[Ine]

Hi XRK

Beautiful work, JR! Neat solder joints.
Only thing I would do different is to place the resistors label up so that you can debug the board visually if there was ever an issue.

If you look closely, you will find that the resistors that are missing a label, is only the 4K99 resistors. These don't come with a label from the manufactor.
Regards
J.R

 

[xrk971]

Cool. Why would they not label their resistors. That’s odd. Saves on cost of printing it I suppose.

 

[xrk971]

That ALD PSU sort of reminds me of something I made years ago with a TracoDCDC followed by some TPS7A4XXX ultra low noise regulators and some soft start ramp up MOSFETs followed by CRCRC. It was very clean. I used it for a nice headphone amp which I gave to good friend.

FFT for 1Vpp into 51ohms

I recently got a few more of the Traco’s to play with. These are 333mA.

 

[Ine]

Hi
I think the Traco Powers are very good. A member in a Norwegian Audio forum is using them in his upcoming MC/MM Riaa. Measurments seems promising

 

[asuslover]

Done !
View attachment 1051397

Ine , your soldering skills are impressive, well done!

 

[Ine]

Hi
I'm going to test XRK's BTSB Buffer-Se/Bal to Se/Bal Buffer in my new pre-amp. Today I use a balanced gain stage with 6dB gain. Op-amp used in this gain stage is OPA1656.
Volume is regulated with two Muses 72320.
Regards
J.R

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[xrk971]

Nice system. The BTSB provides the 6dB gain already. Are you making another gain stage with OPA1656? Nice preamp!

 

[xrk971]

Hi Ine,
Did you get first sound yet? Please let us know how it sounds and works when you get a chance.

 

[Ine]

Hi,
not yet. Have some rewiring in the preamp to do, to get this new board implemented . Maybe next week
J.R

 

[bambadoo]

Hmm, this buffer has caught my attention. Wonder if it is a good match at the output of the raw outputs of my soekris dam1021 dac?
SE to Balanced and from there on direct into a couple of icepower 1200as2 based amps. Volume is digital 32bits float from the dac..
Wondering if it is possible to implement a turn on/off relay at the outputs or something?
Not read the whole thread yet unfortunately but is it still a group buy?

 

[xrk971]

Another member is using the BTSB as output buffer for Soekris to drive balanced input amps.

The BTSB does not have the relay feature but you could implement one yourself using small signal relays easily. Or use my headphone protection solid state relay to do the same thing. Just trigger the relay externally somehow (probably apply DC 1.5v to 5v to the input of the comparators would be a good trigger (negative logic)).

https://www.etsy.com/listing/971912371/ssr-headphone-protection-pcbs?click_key=a7eca0921abad13cb5f2e35883319d49209386f6:971912371&click_sum=e9ae311f&ref=shop_home_active_10

It’s available from my shop, no GB needed.

https://www.etsy.com/listing/833727310/btsb-buffer-sebal-to-sebal-buffer?click_key=f0bf2b93ba77c5cc7119dd77141489e493abaea0:833727310&click_sum=6877000b&ref=shop_home_active_15

There is also a panel mounted version:

https://www.etsy.com/listing/938031032/btsb-panel-mount-sebal-to-sebal-buffer?click_key=cd8349d352f6e2d3fad4a54d4afeb8e828f1a340:938031032&click_sum=a625b29f&ref=shop_home_active_11

 

[bloqhed]

I have an empty TH v1.3 board, and all of the parts on hand to build it, except I don't have any OPA1656's. I do have a handful of OPA1612's, would they work as an acceptable substitute?