With a lot of research and several friend's help (yes, I am a beginner at this) I recently built the 4sUniversal tube preamp and lastly modded the 12au7 Bravo low voltage tube/mosfet hybrid headphone amp. To say I am impressed with the modded Bravo headphone amp mated to a pair of Grado phones would be an understatement.
If I could just get that sound in a line stage.
Rummaging through the net and ran across this 'Borbely balanced tube input mosfet output linestage single ch preamplifier PCB !' from Jim's Audio. It is a low voltage tube/mosfet hybrid similar to the Bravo. Have to try it.
Anyhow, after 4+ weeks of waiting the boards should be here any day now and I 'think' most of the hard to find parts have already arrived from ebay. (hoping these are real parts and not fakes) Mouser is super fast with shipping so the rest of the order awaits till everything else gets here.
It appears a simple, suitable, and reasonably priced +/-24 volt power supply is hard to find so I'm going to try and build this 24V Dual Power Supply Regulated | Circuit Diagram +/- 24v power supply.
Does this power supply look feasible?
What about the vol pot? I find considerable information about the headamp but very little information about the line stage. One thing it neglects to mention is the volume pot.
Does it go at the input or output and what resistance?
Any help on this project is appreciated.
If I could just get that sound in a line stage.
Rummaging through the net and ran across this 'Borbely balanced tube input mosfet output linestage single ch preamplifier PCB !' from Jim's Audio. It is a low voltage tube/mosfet hybrid similar to the Bravo. Have to try it.
Anyhow, after 4+ weeks of waiting the boards should be here any day now and I 'think' most of the hard to find parts have already arrived from ebay. (hoping these are real parts and not fakes) Mouser is super fast with shipping so the rest of the order awaits till everything else gets here.
It appears a simple, suitable, and reasonably priced +/-24 volt power supply is hard to find so I'm going to try and build this 24V Dual Power Supply Regulated | Circuit Diagram +/- 24v power supply.
Does this power supply look feasible?
What about the vol pot? I find considerable information about the headamp but very little information about the line stage. One thing it neglects to mention is the volume pot.
Does it go at the input or output and what resistance?
Any help on this project is appreciated.
power supply is fine.
The 10 nF capacitors are pointless though (also 'harmless', so follow your muse)
Without circuit schematic for your amps, the rest of the discussion kind of dies.
No… i'm not in the mood to go searching endlessly for a achematic!
Your job!
⋅-⋅-⋅ Just saying, ⋅-⋅-⋅
⋅-=≡ GoatGuy ✓ ≡=-⋅
The 10 nF capacitors are pointless though (also 'harmless', so follow your muse)
Without circuit schematic for your amps, the rest of the discussion kind of dies.
No… i'm not in the mood to go searching endlessly for a achematic!
Your job!
⋅-⋅-⋅ Just saying, ⋅-⋅-⋅
⋅-=≡ GoatGuy ✓ ≡=-⋅
Sorry, I am a bit leery of posting other's works. This is from Jim's Audio found here Borbely balanced tube input mosfet output linestage single ch preamplifier PCB ! - JIMS Audio
Attachments
You might consider a low power SMPS for the power supply ?
I found one very cheap for a low power amp I designed on RS Components website.
I found one very cheap for a low power amp I designed on RS Components website.
These are mono boards and somewhere, I read to use separate power supplies for each board's power supply. Do I need one separate power supply for each board or is using one power supply for both boards ok? It would simplify things.
Should I use an smps or would a linear supply be better as a linear +/-24 .6amp supply ($75) can be found at Mouser. I have had very good luck with them and their service has been top notch. They also have a linear 6.2vdc ($20) supply for tube heaters.
Currently have on hand two cute little Antek 6v+6v and two 24v+24v torrids to build power supplies.
Should I use an smps or would a linear supply be better as a linear +/-24 .6amp supply ($75) can be found at Mouser. I have had very good luck with them and their service has been top notch. They also have a linear 6.2vdc ($20) supply for tube heaters.
Currently have on hand two cute little Antek 6v+6v and two 24v+24v torrids to build power supplies.