Hi members, I'm looking for input to help me find a pre-amplifier and amplifier combination. My main input will be my vinyl collection, but not to say I don't have a CD library and of course iTunes. So I'm interested in a pre-amp with at least two phono inputs, with mm/mc selection. Tape and Cd or aux inputs also a must. So I look forward to your useful advice, my budget is up to $2000.00. All suggestions eagerly awaited.
If you can do it yourself, a used dynakit PAS3 and ST70 are the classic responses. Then a driver board from classicvalve.ca can drive down the harmonic distortion from 1% to ? and get you away from unobtainable 7199 tubes to something normal like 12AT7 or something. Replacing the resistors over 100k ohms, with metal film drives down the hiss of the preamp. and replacing the selenium rectifiers with shottky in the preamp and 1n4007 in the power amp pep up the mean time between failure. Of course, electrolytic caps under 10 years old are a given, and possibly new rectifier tube (5AR4) and power tubes (6CA7). I replaced the paper caps in the PAS2 I own with polyester film, it ended up a little bright so until I want to take another round I'm using it with the treble tone control down a little. I had no choice one paper cap had the wax case burned through (on the bottom where I couldn't see it) and changed 9 of them until I found the problem.
The volume pot might need replacing, and the selector switch might need cleaning with an eraser and alcohol. My tone controls and switches are fine at 61 years, as are the 12AX7's, The 7199's are 41 years old and are fine. Exception, mine have been struck by lightning induced surge a few times and the power switches have arced across and needed replaced.
I use mine with moving magnet cartridge (Shure M97), CD player, FM-AM radio, reel to reel tape recorder. The mono FM-AM input can be converted to stereo by a wiring change if you want both CD and computer input. It also has a FM stereo input.
That is if you have efficient speakers. My Peavey SP2XT are 101 db/watt, so my usuall listening power at home is about 1 Vpp. More modern speakers of the acoustic suspension design require much more power even for home use.
Dynaco-doctor.com has the service and construction manuals available for download. There is a whole industry of clones and copies that has existed since 1961 since these were so popular. One source of clone kits is triodeelectronics.com, that generously has many tube datasheets online.
The volume pot might need replacing, and the selector switch might need cleaning with an eraser and alcohol. My tone controls and switches are fine at 61 years, as are the 12AX7's, The 7199's are 41 years old and are fine. Exception, mine have been struck by lightning induced surge a few times and the power switches have arced across and needed replaced.
I use mine with moving magnet cartridge (Shure M97), CD player, FM-AM radio, reel to reel tape recorder. The mono FM-AM input can be converted to stereo by a wiring change if you want both CD and computer input. It also has a FM stereo input.
That is if you have efficient speakers. My Peavey SP2XT are 101 db/watt, so my usuall listening power at home is about 1 Vpp. More modern speakers of the acoustic suspension design require much more power even for home use.
Dynaco-doctor.com has the service and construction manuals available for download. There is a whole industry of clones and copies that has existed since 1961 since these were so popular. One source of clone kits is triodeelectronics.com, that generously has many tube datasheets online.
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Dear me, I thought this was the tube thread. In the solid state realm I have a heavily modified RA88a disco mixer and a heavily modified ST120 transistor amp. The ST120 was a lot of work, www.diyaudio.com/forums/solid-state/156627-dynaco-stereo-120-can-beautiful.html although djoffe is now selling some kits to make it easier by making it a LM3886 amp. Updatemydynaco.com I believe. If I wanted to buy something and had money I would buy a Peavey CS600s for home use, as my CS800s sounds better than the ST70 and the same as the modified ST120. The RA88a has two mag phono inputs, a high level CD input, and a low level mono dynamic mike input I modified to a high level FM radio input. That was a whole lot of work but only $45 for the mixer and parts. www.diyaudio.com/forums/analog-line-level/164102-improving-disco-mixer-mid-fi-performance.html
If I was starting over and didn't have a lot of money, I'd try to buy a Peavey disco mixer for the magnetic phono inputs, and 4 to six more inputs. It would need op amp, circuit upgrades and probably slider pot replacement on some channels, but it would have a schematic and fitting pots available by contrast with the dark horse RA88a. I've never seen one for sale though.
If I was starting over and didn't have a lot of money, I'd try to buy a Peavey disco mixer for the magnetic phono inputs, and 4 to six more inputs. It would need op amp, circuit upgrades and probably slider pot replacement on some channels, but it would have a schematic and fitting pots available by contrast with the dark horse RA88a. I've never seen one for sale though.
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