Thank You very much NP, ZM and MR! Im deeply grateful with your attention. MR the tube guys round here they call SS 'sand amps'. Looks like work on sand amps is going real swell. Cheers!
just finished hand wound inductor (1of 4) for CLC supply using hellenic copper wire 14awg around 50m length. ebay plastic bobbin 8cmx3cm really help to wound it. since i dont have any L meter, using web calculator should give around 4mH, and measured DCR is 0.51 ohm
with 3hrs of working and $8 wire, i think that no any commercial inductor will close to this diy inductor for price/value 😀
i've completed making UMS on 2 heatsink, hand drilling and tapping for 50holes is really good exercise for my muscle. still got another 2 heatsink to be completed
i have question, why most of sample that i find, B+ supply is connected to drain using a screw? i'm planning to use power connector spade
with 3hrs of working and $8 wire, i think that no any commercial inductor will close to this diy inductor for price/value 😀
i've completed making UMS on 2 heatsink, hand drilling and tapping for 50holes is really good exercise for my muscle. still got another 2 heatsink to be completed
i have question, why most of sample that i find, B+ supply is connected to drain using a screw? i'm planning to use power connector spade
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Hello,
I have my 2sj82 L' Amp with the ZV2 CCS up and running with a strange sine wave at clip (see pic) Ive never seen that before. In square wave it rings. Why is it doing that ?
Ive have updated my scheme with actual voltages and notes. I was so excited to get the CCS working!.
Does it look like my operating point pretty high up the load line or is it an oval load with a CCS?
Thank you guys best regards David
I have my 2sj82 L' Amp with the ZV2 CCS up and running with a strange sine wave at clip (see pic) Ive never seen that before. In square wave it rings. Why is it doing that ?
Ive have updated my scheme with actual voltages and notes. I was so excited to get the CCS working!.
Does it look like my operating point pretty high up the load line or is it an oval load with a CCS?
Thank you guys best regards David
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then nothing wrong
you can't expect symmetrical clipping from circuit which isn't symmetrical
read enclosed for example and more insight
(you have sine flipped upside down due to flipped voltage/phase)
regarding square ringing .... either leave it or compensate ......... probably irrelevant to sound in this case
you can't expect symmetrical clipping from circuit which isn't symmetrical
read enclosed for example and more insight
(you have sine flipped upside down due to flipped voltage/phase)
regarding square ringing .... either leave it or compensate ......... probably irrelevant to sound in this case
Interestingly, if we try to bias the stage to saturate more symmetrically, distortion and maximum power are altered, usually for the worse.
This soft saturation is something that makes clipping noticeable only when the THD is very high; It works like a compressor. So, in this conditions, SIT amps makes the sound appear more powerful than really is!
This soft saturation is something that makes clipping noticeable only when the THD is very high; It works like a compressor. So, in this conditions, SIT amps makes the sound appear more powerful than really is!
I recall I hooked my headphones up to one of the LuminAria prototypes just for fun. You could certainly work up a circuit for headphones without much trouble. 🙂
Hi Michael,
What value of output capacitor you used when you tried that? I thought about using LuminAria to drive my headphones (mostly 32 ohm) also, but was held back by the need of using big electrolytic output caps.
if 'lytic is good enough for common spk , why is not good enough for cans ?
you can always bypass it with some proper drek
or go nutz - put 5 big motor runs in parallel
you can always bypass it with some proper drek
or go nutz - put 5 big motor runs in parallel
I just used a big dumb electrolytic, a couple thousand microfarads. I often find that output caps don't sound nearly as bad as their reputation would suggest, but that's a different thread 🙂
Thanks Michael and ZM, makes me want to try again 🙂
Some more questions if you don't mind:
- Since Vds of the output device in LuminAria is quite high, do I need high voltage rated ones (say, 100V).
- Some people said that the turn on thumb from big electrolytic could damage the headphones, is that something I should worry about.
Some more questions if you don't mind:
- Since Vds of the output device in LuminAria is quite high, do I need high voltage rated ones (say, 100V).
- Some people said that the turn on thumb from big electrolytic could damage the headphones, is that something I should worry about.
For turn-on thump you can use an small capacity cap for headphones output or use an timer relay with proper wiring.
Thanks, but I believe C can't be too small or I'll be starting to lose my low frequency. Michael mentioned he used a couple thousand uF, and I think I won't go lower than 2700uF (-3dB freq around 1.9Hz).
Timer relay is an option, though I would like to avoid the extra complexity if possible.
I believe there is no thump with common version , so no reason to have it with can dedicated one
though , that needs confirmation in vivo , with exact iteration you intend to make , in case of changing any important parameter - PSU implementation and Iq - two first things I can think of
though , that needs confirmation in vivo , with exact iteration you intend to make , in case of changing any important parameter - PSU implementation and Iq - two first things I can think of