The simplistic Salas low voltage shunt regulator - Page 76 - diyAudio
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Old 18th July 2009, 04:33 AM   #751
Fanuc is offline Fanuc  United Kingdom
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Quote:
Originally posted by ikoflexer
Before the R6 mod, line regulation

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After the R6 mod, line regulation


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Before the R6 mod, output impedance


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after the R6 mod, output impedance


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Complete bunkem, anyone with any intelligence can see that!

Kevin
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Old 18th July 2009, 05:00 PM   #752
prakit is offline prakit  Thailand
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Hi all,

My first post to this thread. I've hardwired a 5V shunt reg as show in Salas reply to Woodenhead to try it on my Buffalo32S as well. I used 2-LM336Z-2.5V in place of D1 (just happen to have plenty of them around). The output is sitting at 5.6V which should be good for the dac. I used 3 green LED for the CCS ref and I found the voltage drop across R1(10 Ohm) is 1.7V. This translates to 170mA of Iccs. However the DAC is said to draw 125mA. Should I lower the R1 for more Iccs?

I am a shunt reg advocate. I've been using Borbely's super shunt and Allen Wright's HV shunt reg in my ss and tube pre respectively. This reg will replace the Jung/Didden super reg for digital supply in my B32s dac.

My sincere appreciation to Salas and all contributors to this reg here!
Prakit
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Old 18th July 2009, 05:15 PM   #753
Salas is offline Salas  Greece
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No, leave it at 170mA. I intended it to have a margin. Will be happy to know if you could detect some subjective differences after the substitution.
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Old 18th July 2009, 05:28 PM   #754
iko is offline iko  Canada
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Quote:
Originally posted by Fanuc


Complete bunkem, anyone with any intelligence can see that!

Kevin
bunkum = Empty or insincere talk; claptrap.

It's my specialty, as we all know, anyone with any intelligence can see that.
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Old 18th July 2009, 06:03 PM   #755
Salas is offline Salas  Greece
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Quote:
Originally posted by Fanuc
Complete bunkem, anyone with any intelligence can see that!

Kevin
Next time you are in for the bin. Talk electronics and don't offend members.


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Old 18th July 2009, 09:30 PM   #756
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Quote:
Originally posted by prakit
Hi all,

My first post to this thread. I've hardwired a 5V shunt reg as show in Salas reply to Woodenhead to try it on my Buffalo32S as well. I used 2-LM336Z-2.5V in place of D1 (just happen to have plenty of them around). The output is sitting at 5.6V which should be good for the dac. I used 3 green LED for the CCS ref and I found the voltage drop across R1(10 Ohm) is 1.7V. This translates to 170mA of Iccs. However the DAC is said to draw 125mA. Should I lower the R1 for more Iccs?

I am a shunt reg advocate. I've been using Borbely's super shunt and Allen Wright's HV shunt reg in my ss and tube pre respectively. This reg will replace the Jung/Didden super reg for digital supply in my B32s dac.

My sincere appreciation to Salas and all contributors to this reg here!
Prakit
Hey Prakit, thanks for testing the circuit out for me! Do you think that 5.6V might be a little high for the Buffalo? How would the value be brought down a little?

Subjective thoughts on the differences between this and your previous regulator would be very interesting, as Salas says.
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Old 19th July 2009, 07:27 AM   #757
prakit is offline prakit  Thailand
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Default 5V Salas's Shunt Reg in B32S

I installed the reg in the dac last night and left it on for burn-in. This morning I checked it and everything was in order before gave it a listen.

To answer Woodenhead about the Vreg=5.6V, yes, it's slightly high but I think it's absolutely fine. If you use the 4,7V Zener for D1, it should be closer to optimal 5V.

This listening impression is relative to the Jung/Didden reg.
Good news first. Overall the dac sounds more liquid. The mid is slightly sweeter and more fleshed out. However, the good news stops here. It sounds very dull in the hi. The bass(in which I feel is the strength of B32S) is also a bit thin and not very tight. Sorry but I have to say it doesn't sound right.

I have a feeling that some parts are not working at their optimal point. 5V is quite low. Beside the D1 that I substitute with 2xLM336-2.5, I wonder if the choice for Q3 is critical? I can't find a BC550C so I liberally use a 2SC1627A here. All JFet were chosen according to specified Idss.

Best
Prakit
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Old 19th July 2009, 08:59 AM   #758
Tham is offline Tham  Malaysia
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I think more burn in is required before it will sound its best.
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Old 19th July 2009, 11:29 AM   #759
Salas is offline Salas  Greece
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Its possible is not good at 5V or not good for the B32S. I did not feel that at 5V there is a lot of room for the elements. But LM336s maybe not optimal with the current we use for their ccs here. Try a 4V3 or 4V7 Zener and listen again. Also try to use a driving transistor with hfe about 300. If it remains dull (or you just like a sharper sound), it is always scalable for higher voltage and try out in another circuit you may have in the future. Also Tham will let us know what happens with his own DAC.
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Old 19th July 2009, 11:58 AM   #760
Tham is offline Tham  Malaysia
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Added a supertweeter to my fullranger + subs recently and still trying to get proper integration. I will do a comparison between v1 and v2 on my DAC once things are more settled down.
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