Hi mhouston, do you have any info about your single tube preamp (12AU7) design. I have built a lm3875 amp and would like to try my hand at a tube pre. Any suggestions?
Regards
Bix
Regards
Bix
You will have to register with this forum but it will be well worth while:
DIY Audio Projects Forum • Super simple single stage tube preamp
retro-thermionic: 4S Universal valve preamp in a Tea box (4SUTea)
retro-thermionic: Universal - 4S preamp MKIV
retro-thermionic: The Black - 4S preamp MKIII
retro-thermionic: Single Stage Tube Preamp MKII
retro-thermionic: Single Stage Tube preamp
Ohh hell yeah a working amp made of vintage parts...
Sorrry for rubbish quality 😀
Chip in use: LA4140 Sounds good but has pretty freakin loud mains noise problem, what can cause this?!
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Sorrry for rubbish quality 😀
Chip in use: LA4140 Sounds good but has pretty freakin loud mains noise problem, what can cause this?!
An externally hosted image should be here but it was not working when we last tested it.
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I have 2L8 with shiny package not muddy crap shown on the picture...
Got 8 of them, and going to make PCB and will try them as headphone amp.
Got 8 of them, and going to make PCB and will try them as headphone amp.
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I just pulled my LM3875 out if retirement for the day and am blown away at how good this sounds. I recall thinking it was a little light on the bottom end - but listening now it totally belies belief. It's fed by a Teddy Powerreg at 28.5V regulated rails and some tests I did today confirm just now effective the regulation is. It runs through an X-10D clone buffer with genalex gold lion 6922 valves and an alps blue velvet 10 ohm pot.
Lovely sound - detailed full and very easy to listen to.
Lovely sound - detailed full and very easy to listen to.
An externally hosted image should be here but it was not working when we last tested it.
Just built and tube and chips amp myself. Found it sounded even better with a tube preamp. Nice build.
That is a nice and straightforward looking build. Clean and easy to follow (even with the blurry cell phone picture). How long has it been in retirement?
I switch things around. A lot. Too much for my wife to not notice and shake her head at me. Things (old and new) always sound much more different when you play audio through just one amplifier for a long time. Listening "fatigue" is what I call it and you start to favour one type more and more and you forget what the others sound like because your ears get too used to that one sound you are using.
Swapping it out with regularity keeps this condition away.
And that is the argument/reasoning I use when a new project, new amplifier, new vintage stereo, set of tubes, or a new set of boards and parts come rolling in. So build more amplifiers!
I found use for those LA4140 chips... They drive my LM3915 VU meter Tower, i somehow managed to destroy the 386 chip but now it works again but with a sanyo chip 😀
http://youtu.be/X-urfcKvtGg
Lots of fun and a bit light for my department... Freakin dark in here but not anymore 😎
http://youtu.be/X-urfcKvtGg
Lots of fun and a bit light for my department... Freakin dark in here but not anymore 😎
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I just finished a first playing state of a Peter Daniel’s premium LM3875 Amplifier Kit. This one has a dedicated rectifier board per channel and unusual single 400Vac with centre tapped secondary windings, which I salvaged from an old Rotel power amp. Peter advised me not to use a single transformer, for the risk of getting a hum problem with two rectifier boards, but since I already had all the parts I gave it a try anyway. Fortunately I didn’t notice any hum yet. To use centre Tapped, means only using 4 diodes per side instead of eight. I also put in a slowstart board, which I’m not sure is needed but at least turning the amp on/off creates no audible noise which is what I was after.
This is my first experience with a Gainclone (and only the second amp I ever build from scratch) and I can already tell this is a seriously good amp, maybe a bit relentless even, I had to plug in my old speakers which are less analytical to keep things more musical. Obviously the new components still need to burn in but I’ve had a few goose bump moments allready.. 🙂
Thanks to everybody on this forum for inspiring me to build this amp.
For people still on the fence about one of these. This amp is ridiculously easy to build, even I could do it & Peter Daniel’s Kit’s make it even easier (www.audiosector.com)
Here are some pictures. I went for this form factor to match my Audio-GD NFB-28 DAC/Pre-amp.
This is my first experience with a Gainclone (and only the second amp I ever build from scratch) and I can already tell this is a seriously good amp, maybe a bit relentless even, I had to plug in my old speakers which are less analytical to keep things more musical. Obviously the new components still need to burn in but I’ve had a few goose bump moments allready.. 🙂
Thanks to everybody on this forum for inspiring me to build this amp.
For people still on the fence about one of these. This amp is ridiculously easy to build, even I could do it & Peter Daniel’s Kit’s make it even easier (www.audiosector.com)
Here are some pictures. I went for this form factor to match my Audio-GD NFB-28 DAC/Pre-amp.
Attachments
Some better pictures
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
Nice build gadut, what's the other board in front of the My Ref board on the left?
Here is a link to a "Disaster Recovery" 😱 post for an attempt to ship a chip based amp build.
This is the story of the first effort if your'e interested.
This is the story of the first effort if your'e interested.
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Thanks Troy, but this is a different flavor of MyRef. These are Dario Inserra's Fremen Edition - RC version. Still haven't built the "Final" version, but the release candidate produces excellent sounds.
The bad channel is on one of the earlier V1.3 offerings from linuxguru. I still don't have that corrected - next week's priority. It's well worth the effort as the V1.3s produce an elegant "Class A" type sound when equipped with some of the modules Siva is developing. The opamps are socketed (as you can see similar in Gadut's photo above) and allow experimentation. The FEs are for the most part, SMD components and aren't as mod friendly.
The bad channel is on one of the earlier V1.3 offerings from linuxguru. I still don't have that corrected - next week's priority. It's well worth the effort as the V1.3s produce an elegant "Class A" type sound when equipped with some of the modules Siva is developing. The opamps are socketed (as you can see similar in Gadut's photo above) and allow experimentation. The FEs are for the most part, SMD components and aren't as mod friendly.
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