may output transistors are biased about 40 mA each (with four 1N4934 diodes because i have them ....)
Just finished the first listen. I can only say that the performance of this amplifier has gone beyond my wildest expectations😱; never heard another SS amplifier so good; this with a "standard" PS(classic 317-337 with preregulation). I'm driving it with a tube preamplifier and it's a mate made in heaven.
Thank you for sharing this project with this forum.
Now i want to change and try the PS with a shunt regulated one. What concerns me a little is the fact that i noted that the power consumption under stress( an input signal of 5V) doubles the idle consumption. Can i still use a shunt PS? Set at what current?
Thanks again and sorry for my bad english.
Thank you for telling us what you heard. Your English is plenty good enough. It also exceeded my expectations. Audio sound hasnt progressed much but this is a quantum leap forward. IMHO, of course.... and I just need to hear from others to verify it.
The current draw is rather high and it should do very well with a shunt reg circuit. In fact it is my favorite PS. But I havent listen to one on this HPA, yet. Since you have listened to it with series, you are in a good position to say how a shunt compared when you apply it.
Depending on load Z and PS voltage used (12-24vdc) I would make the supply capable of at least 400mA for 2 amps and low Z load/headphones.
THx-RNMarsh
The current draw is rather high and it should do very well with a shunt reg circuit. In fact it is my favorite PS. But I havent listen to one on this HPA, yet. Since you have listened to it with series, you are in a good position to say how a shunt compared when you apply it.
Depending on load Z and PS voltage used (12-24vdc) I would make the supply capable of at least 400mA for 2 amps and low Z load/headphones.
THx-RNMarsh
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Putting together a Kevin Gilmore Golden Reference LV power supply (+/-15 vdc or +/-20vdc) for my long set aside Marsh Headphone Amp. The KGGRLV is a series voltage regulator based on a Walter Jung design from an old Audio Amateur article, and the Krell CAST power supply.
http://www.head-case.org/forums/topic/12269-goldenreference-low-voltage-power-supply/
With an inexpensive 2x 18 or 24vac, 30 watt R-core from EBay, seems taylor made for the Marsh Headphone Amp.
Just waiting on a few last parts to stuff the PCB. Will report back with results later.
http://www.head-case.org/forums/topic/12269-goldenreference-low-voltage-power-supply/
With an inexpensive 2x 18 or 24vac, 30 watt R-core from EBay, seems taylor made for the Marsh Headphone Amp.
Just waiting on a few last parts to stuff the PCB. Will report back with results later.
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That is a great regulator design from WJ. Cant wait to hear your results.
😎🙂
-Richard
😎🙂
-Richard
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1. RN Marsh headphone amp
2. 317/337 based virtual ground PS
3. 10x8 Dual Power supply DC board with RCR(L)C filter
@Dirty
PS
I need JFETs. Plenty available on Aliexpress, do I need some info to choose seller or pull trigger randomly?
2. 317/337 based virtual ground PS
3. 10x8 Dual Power supply DC board with RCR(L)C filter
@Dirty
PS
I need JFETs. Plenty available on Aliexpress, do I need some info to choose seller or pull trigger randomly?
Anybody please tell me how can i get the circuit diagram (schematics) along with parts list of this famous Marsh headphone amp from Linear Audio? I wish I could make one of this so famous headphone amp!!
The SMT version are in current production and you can use an adapter (various sellers on EBay) to do the trick.
I did Rev2 of the boards to accommodate SMT -- these boards are offered at cost in deference to Dr. Marsh's IP.
Sikahr is not selling the board. He just shared his board layout at the board house (Dirty PCB) so that anyone can order the board from Dirty PCB directly. At $25 for 10 boards shipped, it is quite a bargain, and there is no excuse not to try this wonderful amp. Buy the article from LA, everything is all set then.
Hi Jack,
don't want to use SMD transistors for first build, easier to do matching with THT parts.
Thx anyway.
BR Nenad
don't want to use SMD transistors for first build, easier to do matching with THT parts.
Thx anyway.
BR Nenad
The LM317/LM337 should be replaced with LT1963A and LT3015 -- you'll be pleased with the results.