I am getting the itch to build a new preamp. There is nothing really wrong with my current 124B common cathode resistive plate load preamp but I'd like to try something new.
My current setup is as follows
- Systemdek IIX (Rega RB330 arm) with Sumiko Songbird MC cartridge (0.5mV) ->
- Pass Pearl 2 phono (55dB 562Av) ->
- 124B common cathode preamp (22dB 14Av) ->
○ Pass FirstWatt F6 (input sensitivity 2.83V) ->
○ Anthony Gallo Subwoofer Amp ->
- Anthony Gallo Reference 3.1 speakers
Some of the things I'd like in a new preamp
- Low gain, based on my setup I need ~10Av of gain
- Low impedance output (input impedance of the F6 is 100K)
- Design that isn't super picky about PSU design
Because I just want to have fun building a new amp here are a few things I am going to try and incorporate 🙂
- Wood exterior chassis
- VU meters
- Input relay switching
- A volume control other than the Alps I've usually used
Thoughts on some design to look in to?
I was looking at the Akido/TubeCAD CCDA design, seemed intriguing.
My current setup is as follows
- Systemdek IIX (Rega RB330 arm) with Sumiko Songbird MC cartridge (0.5mV) ->
- Pass Pearl 2 phono (55dB 562Av) ->
- 124B common cathode preamp (22dB 14Av) ->
○ Pass FirstWatt F6 (input sensitivity 2.83V) ->
○ Anthony Gallo Subwoofer Amp ->
- Anthony Gallo Reference 3.1 speakers
Some of the things I'd like in a new preamp
- Low gain, based on my setup I need ~10Av of gain
- Low impedance output (input impedance of the F6 is 100K)
- Design that isn't super picky about PSU design
Because I just want to have fun building a new amp here are a few things I am going to try and incorporate 🙂
- Wood exterior chassis
- VU meters
- Input relay switching
- A volume control other than the Alps I've usually used
Thoughts on some design to look in to?
I was looking at the Akido/TubeCAD CCDA design, seemed intriguing.
Last edited:
The best sound I have yet found is a 2a3 or 6B4G preamp. Low output impedance, plenty of drive.
An easy tube to work with and plenty of schematics and data online. 2a3 with AC filaments or probably even better, 6B4G with Rod Coleman's latest filament regs (Lyrima audio). Could be a simple resistor load with cathode bias and a DC Link bypass cap. Or active load, plate choke or OPT.
I find the sound with a 6B4G with Coleman regs very detailed, dynamic and smooth. Love it.
An easy tube to work with and plenty of schematics and data online. 2a3 with AC filaments or probably even better, 6B4G with Rod Coleman's latest filament regs (Lyrima audio). Could be a simple resistor load with cathode bias and a DC Link bypass cap. Or active load, plate choke or OPT.
I find the sound with a 6B4G with Coleman regs very detailed, dynamic and smooth. Love it.
Salas 6V6 will give you ~6-7X gain.
An Aikido or CCDA with a 6SN7 or 6CG& up front, and a 6DJ8 or 6n1p output would be a good choice too- with me leaning heavily towards a CCDA with a 6CG7/6DJ8 if you go that way.
An Aikido or CCDA with a 6SN7 or 6CG& up front, and a 6DJ8 or 6n1p output would be a good choice too- with me leaning heavily towards a CCDA with a 6CG7/6DJ8 if you go that way.
Member
Joined 2009
Paid Member
I suggest a preamp with feedback, gives you low gain more easily, gives low output impedance, good channel to channel gain matching.
I can’t recommend a design based off experience but I can say that I have two such projects on the go, a clone of the Shindo Claret, and a clone of the Kondo M7.
I can’t recommend a design based off experience but I can say that I have two such projects on the go, a clone of the Shindo Claret, and a clone of the Kondo M7.
Aikido line stage with all 6DJ8s. If gain is too high Broskie provided a way to tame it without feedback. A CCDA might have too much gain, Broskie's two stage CCDA Tetra phono stage makes for a decent phono pre, IMHO.
S.
S.