Those resistors are just a test point for easily finding the current in each Vref by their voltage drop. Useful when skipping the signal section and modding the regulators section for higher voltage setting as a general PSU. Enough people were after that alternative use of the boards back in the day. There was a thread about that also. It was 10R in the Mez but was re-designated as 1R in the Hypno for direct mV=mA indication after I saw most interested people's DMMs proved accurate enough.
Makes no practical performance difference if 10R, 1R, or a jumper link.
Makes no practical performance difference if 10R, 1R, or a jumper link.
No sir, i was retiring from the audio world for the past three years, just keeping an awful looking amplifier, anything else been sold, including the buffer itself. But still the buffer is a gem of performance which i miss it today
. Now, i start to build the audio again, oh boy what an ambiguity of me, left the audio, and then start to build them again Thanks.
I bought few matched pairs of k170 from japan, they matched the Idss using 10V. Should I re-test the Idss value using 9V before I use it?
The correct Idss is @ 10Vds and Tj=25degrees C and low duty cycle test and lost of other things we amateurs cannot ever hope to achieve accurately.
Any Idss testing we do is an approximation.
The best we can do well, maybe even better than the manufacturers, is to compare devices. Here we can develop a methodology that gives ultra accurate COMPARISONS even though absolute accuracy is out the window.
An excellent example of this is the Hamon divider. Have you read about it?
It can be used to obtain supremely accurate 1:4 & 1:9 and 1:16 and 1:25 RATIOS that none of our "absolute" instruments can ever approach.
Any Idss testing we do is an approximation.
The best we can do well, maybe even better than the manufacturers, is to compare devices. Here we can develop a methodology that gives ultra accurate COMPARISONS even though absolute accuracy is out the window.
An excellent example of this is the Hamon divider. Have you read about it?
It can be used to obtain supremely accurate 1:4 & 1:9 and 1:16 and 1:25 RATIOS that none of our "absolute" instruments can ever approach.
Thanks Siberia.
The p.millet Uniamp uses a Sowter 3575 Phase splitter at input which seems to have much higher impedance. Another question - would I need a preamp?
Regards
Thanks a lot stajo. Good to go then
. First build with tubes and have to relearn a lot of details.Regards
You can use either of your sets.
With 10Vds and 7.8mA they will each be dissipating 78mW (19.5% of Pmax, if Ta=25degrees C).
Using the 9.6mA set will result in 96mW dissipation (24% of Pmax).
Both are well below the 200mW which is the recommended 50% of Pmax for these devices.
A more relevant test would be how close the two channels get to zero output offset, with one set, or the other.
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Hey everyone!
I have used now my hotrodded DCB1 for quite a time. I was thinking about building a new case and wanted to ask a question.
I really like those cases from italy (modushop) where the heatsinks are actually the sidewalls. Now when I have my dcb1-pcb in the middle of the case i would have to connect the power transistors mounted on the heatsinks with the pcb using a about 15-20cm long cable (thick enough...). So does this somehow change the sound? Of course this would not have an effect on the elctrical connections but maybe due to latency or something?
Or is this just nonsense
as the power transistor are only used for the shunt itself so there is no audiosignal passing those transistors anyway?
Also I wanted to know what are the most commonly used caps parallel to the diodes? (0.22/100 uF).
At the moment I use a "0.22uF 1000Vdc Mundorf Mcap Supreme EVO Capacitor" and I am quite happy with it but due to the new case I am thinking of including some changes in the DCB1
Thanks everyone!
I have used now my hotrodded DCB1 for quite a time. I was thinking about building a new case and wanted to ask a question.
I really like those cases from italy (modushop) where the heatsinks are actually the sidewalls. Now when I have my dcb1-pcb in the middle of the case i would have to connect the power transistors mounted on the heatsinks with the pcb using a about 15-20cm long cable (thick enough...). So does this somehow change the sound? Of course this would not have an effect on the elctrical connections but maybe due to latency or something?
Or is this just nonsense
as the power transistor are only used for the shunt itself so there is no audiosignal passing those transistors anyway? Also I wanted to know what are the most commonly used caps parallel to the diodes? (0.22/100 uF).
At the moment I use a "0.22uF 1000Vdc Mundorf Mcap Supreme EVO Capacitor" and I am quite happy with it but due to the new case I am thinking of including some changes in the DCB1
Thanks everyone!