Thank you !
And a simple tube preamplifier, for a 2x100W SS amplifier. Just a source selector, a Baxendall tone controler and a vfd vu-meter.
Attachments
SP14 and VTA ST 70
I am just a kit builder and are currently listening to a pre and power amp from tubes4hifi. Brilliant sound. I manage to put in about 1-2 hours listening during the week after work, more on the weekends.
The pre is a design around 6SN7, regulated power supply and three separate toroids. I modded the kit in such that I used silver / teflon wires for signal wireing, selector and volume control from Goldpoint, Mundorf Gold/Silver coupling caps. Bought 1954 NOS Sylvania's from Vintage Tube Service. Great stuff (dumped the Russian NOS Sovtek).
The VTA ST 70 is a kit from Bob Latino with russian PIO caps. I prefer Gold Lion KT77 in it the most (2nd best EL34, 3rd KT88).
As I have no electronics background I now bought a book about tube amps and circuit designs in an attempt to learn and to design one myself. I would like to try a SE type amp.
This is a great hobbie and gives so much pleasure! What would life be without music!
Best
Michael
I am just a kit builder and are currently listening to a pre and power amp from tubes4hifi. Brilliant sound. I manage to put in about 1-2 hours listening during the week after work, more on the weekends.
The pre is a design around 6SN7, regulated power supply and three separate toroids. I modded the kit in such that I used silver / teflon wires for signal wireing, selector and volume control from Goldpoint, Mundorf Gold/Silver coupling caps. Bought 1954 NOS Sylvania's from Vintage Tube Service. Great stuff (dumped the Russian NOS Sovtek).
The VTA ST 70 is a kit from Bob Latino with russian PIO caps. I prefer Gold Lion KT77 in it the most (2nd best EL34, 3rd KT88).
As I have no electronics background I now bought a book about tube amps and circuit designs in an attempt to learn and to design one myself. I would like to try a SE type amp.
This is a great hobbie and gives so much pleasure! What would life be without music!
Best
Michael
Attachments
Nice clean build on both- looks great! Beautiful job on the preamp- both the top and the woodworking look very clean and precise. How did you do the lettering?
I can recommend a couple books if you're interested:
"Understanding Hi-Fi Circuits" by Normal Crowhurst
"Principles of Power" by Kevin O'Connor
Both are (or were recently) available from Antique Electronic Supply in Arizona.
Reading anything Crowhurst wrote is always very appealing. Really shows how much was known way back when- the "Wisdom of the Ancients" but in plain english.
O'Connor's book is more of a compendium. It doesn't deal with the fundamentals as much as Crowhurst but contains a vast array of ideas and amplifier circuit topologies, and gives an outline of how each works and pitfalls to avoid. A great "Idea Book".
Music, audio engineering and the listening experience all combine to give us a chance to experience the art of the composer/performer and to complement that by offering us a deep involvement in the art of our own creation.
A great hobby indeed!
I can recommend a couple books if you're interested:
"Understanding Hi-Fi Circuits" by Normal Crowhurst
"Principles of Power" by Kevin O'Connor
Both are (or were recently) available from Antique Electronic Supply in Arizona.
Reading anything Crowhurst wrote is always very appealing. Really shows how much was known way back when- the "Wisdom of the Ancients" but in plain english.
O'Connor's book is more of a compendium. It doesn't deal with the fundamentals as much as Crowhurst but contains a vast array of ideas and amplifier circuit topologies, and gives an outline of how each works and pitfalls to avoid. A great "Idea Book".
Music, audio engineering and the listening experience all combine to give us a chance to experience the art of the composer/performer and to complement that by offering us a deep involvement in the art of our own creation.
A great hobby indeed!
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Mike
Get a quad of the Russian 6P3SEs or the 6L6gc RCA black plates..Either of those really kick that amp in the *** even more..I hope you are using the 12AU7 or Equivalent tubes in the driver-phase-splitter because you will have too much gain with 12At7s. Nice amp BTW
Mikey
The diagram if is possible.
Dear friend, you made one of my old dreams, tell us how it sound, the most important think from a beauty girl is not how looks. But its looks like a young girl anyway. Me and some body likes to see the bones and guts of the beast. Show us the electronic diagram please.
Dear friend, you made one of my old dreams, tell us how it sound, the most important think from a beauty girl is not how looks. But its looks like a young girl anyway. Me and some body likes to see the bones and guts of the beast. Show us the electronic diagram please.
These amps have a similar sound to Single ended but lots of power; they have the same distortion foot print like Single ended.
I use horn loaded speakers using Altek 15 inch and JBl tweeters 2452 , so the amp has to be very quiet. I got a lot of Ex military and black and white TV transformers; I used toriodals for the HT due to the much better regulation. The transformers are so big so I built the amps on two chassis. I also built two mono-blocks{Separate Power supplies} for a freind he has used them for 17 years and never had to change a single tube not even the Russian made 811A's.
On two chassis these amps take forever to make just wiring the two cannon sockets takes days. I have also made them on single chassis using C core transformers, the output trans are Sowter. I recently bought two Hammond 280 watts transformers 1.9K P-P to make two more amps, the Sowters cost a fortune. you can also use 805's,812,s 811a's,572b's. The Chinese 572b's sound better than the Russian or USA made 811's, the Russian 572b's cost too much. Not sure how long the Chinese tubes would last.
I will scan the circuit.
Phil
I use horn loaded speakers using Altek 15 inch and JBl tweeters 2452 , so the amp has to be very quiet. I got a lot of Ex military and black and white TV transformers; I used toriodals for the HT due to the much better regulation. The transformers are so big so I built the amps on two chassis. I also built two mono-blocks{Separate Power supplies} for a freind he has used them for 17 years and never had to change a single tube not even the Russian made 811A's.
On two chassis these amps take forever to make just wiring the two cannon sockets takes days. I have also made them on single chassis using C core transformers, the output trans are Sowter. I recently bought two Hammond 280 watts transformers 1.9K P-P to make two more amps, the Sowters cost a fortune. you can also use 805's,812,s 811a's,572b's. The Chinese 572b's sound better than the Russian or USA made 811's, the Russian 572b's cost too much. Not sure how long the Chinese tubes would last.
I will scan the circuit.
Phil
811A circuit
811A circuit as i built it. original Power supply circuit uses mercury vapour rectifiers I considered the Mv rectifiers would make the amp too big.
I used big toriodals and a bridge circuit; Choke input as you need very good regulation as you do with screen drive using EL509's as Zero bias triodes. I think best to use two heater supplies, so you can measure the current draw using two 10 ohm resistors to earth. Very important to have a slow turn on; protects the 6BL7's as the 811's /572b's heat up very fast, compared to the 6BL7's.
You could use sweep tubes instead of 811's, but when i tried them did not like the sound, at least with 811/572's you can use 70 ma current draw. 600 volts is the max with 811A's, less with 811's. 600 volts gives you 100 watts.
i have never tried using Mosfets instead of the 6BL7's as 6Bl7's are cheap and trouble free.
Phil
811A circuit as i built it. original Power supply circuit uses mercury vapour rectifiers I considered the Mv rectifiers would make the amp too big.
I used big toriodals and a bridge circuit; Choke input as you need very good regulation as you do with screen drive using EL509's as Zero bias triodes. I think best to use two heater supplies, so you can measure the current draw using two 10 ohm resistors to earth. Very important to have a slow turn on; protects the 6BL7's as the 811's /572b's heat up very fast, compared to the 6BL7's.
You could use sweep tubes instead of 811's, but when i tried them did not like the sound, at least with 811/572's you can use 70 ma current draw. 600 volts is the max with 811A's, less with 811's. 600 volts gives you 100 watts.
i have never tried using Mosfets instead of the 6BL7's as 6Bl7's are cheap and trouble free.
Phil
Attachments
An externally hosted image should be here but it was not working when we last tested it.
This is my daily mono setup, sorry for the lack of a true pic, as my camera is dead right now. It's a push pull pair of 6V6's, that are cathode biased, I added a choke some time ago. The phase splitter is a 6SL7 and the phono preamp consists of two metal 6SC7's. I have the amp running into a 1958 voice of music extension speaker, I believe a model 12 or something along those lines, with you guessed it, a 12 inch jensen. Thanks for reading my first post guys.
