slbender
New Member
Greetings Audio People!
Steven here in suburbia close to New York in the USA...
I was always into music and equipment, and I now make my own SET tube amps from the bare chassis up. My Tube Preamp is a modification of the old Dynaco PAS 3x, of which I have two, and my two SET Amps. I also two older tube amps, one that needs repair but I haven't had the time to work on it. I also have preamps and amplifiers that use transistors, and Mosfets and integrated circuits. I'll admit some of the recent and more expensive Integrated Circuit's have greatly improved sound - those produced during the past ten or so years, some solid state stuff can be quite good these days, about 90% of what tubes can do!
For input, I like Reel Tapes, Vinyl, and SACD's can be neat too. I've got half a dozen working and semi-working older Reel to Reel Tape Decks; and a pair of 4 way speakers I made several decades ago. Ten years or so back a friend and I mounted a carbon fiber arm on my old AR-XA turntable, boys and girls that is so neat!
My other three belt drive TT's include a Thorens TD-145, a TD-160, and a weird Stanton that uses a proprietary headshell (really dumb idea) and large round opposing magnets for the platter bearing (really neat idea) - Its True!
My two Direct-Drive TT's are the Technics SP-15 and a much simpler Sony. I have been working to repair my broken Technics SP-15. About a week back, with two other techie/engineers, we were troubleshooting two identical SP-15 turntable's with two very different problems. We may be on the track of solving the failure on mine - it was spinning way too fast. While I really didn't believe the Laser Tachometer reading, it clearly showed 440 rpm instead of 33.3 rpm. Still, my friend swears that his Tach unit is dead-on-accurate. UPDATE - we did get the Technics spinning at 33.3 a few days back, but it occasionally gets jumpy, and does a backwards/forwards jig.
Another current project is a Hot Air Desoldering Tool, that I started to modify, which (I hope) will allow me to work with Surface Mount Printed Circuit Boards. Between regular soldering and hot air, I hope to modify and improve some of the lower and middle of the line Sony SACD Players - for Even Better Sound. While vinyl is still king, it has some basic deficiencies that even direct to dist and minimal recording chain advances can't solve. I heard a really top-of-the-line Sony SCD-XA5400ES at a friend's house, and SACD's can sound really, really good!
My current / newest SET Amp - its from 8 years ago. I started working on an even newer one, but ran out of space inside the chassis (bummer) so I never finished it.
My First SET Amp was similar, but less complex using a 12AX7 driving paralleled 10BQ5's, it was Six Watts per channel, in a smallish chassis 13 x 10 x 4 inches form-factor, and it weighed in at about: 36 lbs.
Here's the 411 on the SET Amp pictured.
For my 2nd SET Amp... First, I tossed out the book by F. Langford Smith (1953) 4th Edition - I decided: being sixty years old, that Bible of Audio Design is just not the way to design a SET Amp to drive a complex Speaker Load. Within months I came up with a Revolutionary and Totally Unique All 5687 Tube Circuit. It can also use 7044, 7119, E182CC, or a bunch of 6900's if I can ever afford them, etc. This I built from a naked 10 x 13 x 4 inch steel chassis maybe eight years ago.
A true SET Amp with zero global feedback, is produces 6 Watts per channel; uses a 300 Volts B+; and has built-in: Power Conditioning; 1:1 Isolation Transformer; Switching Power Supply; Two Separate High Voltage Capacitor Banks (one for each Channel under all those bias controls); and uses a Defined Startup Sequence - like in a Missile Silo (but not requiring the turning of two keys simultaneously); Delayed Plate Voltages via - Timers and Relays.
SET Amp Specs: 12 Watts / 2 channels / 12 lbs. (with the steel perforated cover, without the carry-around case - not seen). Bass straight down to hell; Purrfect Midrange; the Sweetest Extended Treble. A great sounding amp, from minute one, even I was amazed the first dozen or so times I listened to it.
Keep your tubes warm and glowing,
-Steven
Steven here in suburbia close to New York in the USA...
I was always into music and equipment, and I now make my own SET tube amps from the bare chassis up. My Tube Preamp is a modification of the old Dynaco PAS 3x, of which I have two, and my two SET Amps. I also two older tube amps, one that needs repair but I haven't had the time to work on it. I also have preamps and amplifiers that use transistors, and Mosfets and integrated circuits. I'll admit some of the recent and more expensive Integrated Circuit's have greatly improved sound - those produced during the past ten or so years, some solid state stuff can be quite good these days, about 90% of what tubes can do!
For input, I like Reel Tapes, Vinyl, and SACD's can be neat too. I've got half a dozen working and semi-working older Reel to Reel Tape Decks; and a pair of 4 way speakers I made several decades ago. Ten years or so back a friend and I mounted a carbon fiber arm on my old AR-XA turntable, boys and girls that is so neat!
My other three belt drive TT's include a Thorens TD-145, a TD-160, and a weird Stanton that uses a proprietary headshell (really dumb idea) and large round opposing magnets for the platter bearing (really neat idea) - Its True!
My two Direct-Drive TT's are the Technics SP-15 and a much simpler Sony. I have been working to repair my broken Technics SP-15. About a week back, with two other techie/engineers, we were troubleshooting two identical SP-15 turntable's with two very different problems. We may be on the track of solving the failure on mine - it was spinning way too fast. While I really didn't believe the Laser Tachometer reading, it clearly showed 440 rpm instead of 33.3 rpm. Still, my friend swears that his Tach unit is dead-on-accurate. UPDATE - we did get the Technics spinning at 33.3 a few days back, but it occasionally gets jumpy, and does a backwards/forwards jig.
Another current project is a Hot Air Desoldering Tool, that I started to modify, which (I hope) will allow me to work with Surface Mount Printed Circuit Boards. Between regular soldering and hot air, I hope to modify and improve some of the lower and middle of the line Sony SACD Players - for Even Better Sound. While vinyl is still king, it has some basic deficiencies that even direct to dist and minimal recording chain advances can't solve. I heard a really top-of-the-line Sony SCD-XA5400ES at a friend's house, and SACD's can sound really, really good!
My current / newest SET Amp - its from 8 years ago. I started working on an even newer one, but ran out of space inside the chassis (bummer) so I never finished it.
My First SET Amp was similar, but less complex using a 12AX7 driving paralleled 10BQ5's, it was Six Watts per channel, in a smallish chassis 13 x 10 x 4 inches form-factor, and it weighed in at about: 36 lbs.
Here's the 411 on the SET Amp pictured.
For my 2nd SET Amp... First, I tossed out the book by F. Langford Smith (1953) 4th Edition - I decided: being sixty years old, that Bible of Audio Design is just not the way to design a SET Amp to drive a complex Speaker Load. Within months I came up with a Revolutionary and Totally Unique All 5687 Tube Circuit. It can also use 7044, 7119, E182CC, or a bunch of 6900's if I can ever afford them, etc. This I built from a naked 10 x 13 x 4 inch steel chassis maybe eight years ago.
A true SET Amp with zero global feedback, is produces 6 Watts per channel; uses a 300 Volts B+; and has built-in: Power Conditioning; 1:1 Isolation Transformer; Switching Power Supply; Two Separate High Voltage Capacitor Banks (one for each Channel under all those bias controls); and uses a Defined Startup Sequence - like in a Missile Silo (but not requiring the turning of two keys simultaneously); Delayed Plate Voltages via - Timers and Relays.
SET Amp Specs: 12 Watts / 2 channels / 12 lbs. (with the steel perforated cover, without the carry-around case - not seen). Bass straight down to hell; Purrfect Midrange; the Sweetest Extended Treble. A great sounding amp, from minute one, even I was amazed the first dozen or so times I listened to it.
Keep your tubes warm and glowing,
-Steven
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