Hey all,
My system is all SS these days and I think the phono pre could be a reasonable component to incorporate tubes.
In an attempt to scope the discussion, I will ask for opinions on the quality of the designs in some of the more readily available kits such as:
Or well-proven designs using 6922 or 5842 (of which I have quite a few nice NOS tubes).
Thanks !
My system is all SS these days and I think the phono pre could be a reasonable component to incorporate tubes.
In an attempt to scope the discussion, I will ask for opinions on the quality of the designs in some of the more readily available kits such as:
- SunValley EQ1616D -- https://www.diyaudio.com/community/threads/eq1616d-phono-amp.345254/
- Bottlehead Eros 2 -- https://bottlehead.com/product/eros-2-phono-preamplifier-kit/
- ANK L1 phono -- https://ankaudiokits.com/product/l1-phono/
- Glass-ware Tetra or PH-2
Or well-proven designs using 6922 or 5842 (of which I have quite a few nice NOS tubes).
Thanks !
If you have lots of tubes, just build several phono preamps. You can even switch the same power supply
around for all of them. The small chassis won't cost that much.
around for all of them. The small chassis won't cost that much.
There are many more preamps than those, and each will have some who like them.
Which is best is a matter of opinion, and yours is the only one that matters.
Don't think the schematics of the first three are available anyway.
Just start building, you can always do another one. They don't cost that much in parts.
Try to find some inexpensive chassis.
Which is best is a matter of opinion, and yours is the only one that matters.
Don't think the schematics of the first three are available anyway.
Just start building, you can always do another one. They don't cost that much in parts.
Try to find some inexpensive chassis.
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If you already have some tubes, you could choose designs that use the tubes you have.
6922 = E88CC = 6DJ8 = ECC88 = 6N23P = 7308 ... Well, not 100% exactly, but really, really close.
The whole 6DJ8/ECC88 family is very popular for use in phono preamps. There are so many well-regarded circuits that use these triodes.
Check out kevinkr's Muscovite Mini III (which uses 6N23P, but 6922 will sub fine).
https://www.diyaudio.com/community/threads/the-muscovite-mini-iii-6n23p-phono-stage.273817/
The RJM Phono Preamp is popular. It's very simple. Far simpler than the Muscovite Mini III.
https://phonoclone.com/diy-pho3.html
https://www.diyaudio.com/community/threads/building-the-rjm-6dj8-phono-preamp.380394/
5842 is a nice tube. I was just looking at a Borbely design that's supposed to be good (although I haven't built one or heard one).
https://audioxpress.com/article/borbely-riaa-preamp-with-tubes-project-remembered-and-revisited
There are many, many tube phono preamp designs. If you search the Tubes/Valves forum and Analog Source forum here on diyAudio, you'll find a lot of good looking possibilities.
rayma is right about opinions on what is 'best'. I've been on a phono preamp adventure for the last year or so, and have gone from 12AX7s and 12AT7s to FET/12AU7 cascode with 6DJ8 output, to an all op-amp design... and what I think is 'best' keeps changing. If I can't decide what's best for me, how can I decide what's best for somebody else?
6922 = E88CC = 6DJ8 = ECC88 = 6N23P = 7308 ... Well, not 100% exactly, but really, really close.
The whole 6DJ8/ECC88 family is very popular for use in phono preamps. There are so many well-regarded circuits that use these triodes.
Check out kevinkr's Muscovite Mini III (which uses 6N23P, but 6922 will sub fine).
https://www.diyaudio.com/community/threads/the-muscovite-mini-iii-6n23p-phono-stage.273817/
The RJM Phono Preamp is popular. It's very simple. Far simpler than the Muscovite Mini III.
https://phonoclone.com/diy-pho3.html
https://www.diyaudio.com/community/threads/building-the-rjm-6dj8-phono-preamp.380394/
5842 is a nice tube. I was just looking at a Borbely design that's supposed to be good (although I haven't built one or heard one).
https://audioxpress.com/article/borbely-riaa-preamp-with-tubes-project-remembered-and-revisited
There are many, many tube phono preamp designs. If you search the Tubes/Valves forum and Analog Source forum here on diyAudio, you'll find a lot of good looking possibilities.
rayma is right about opinions on what is 'best'. I've been on a phono preamp adventure for the last year or so, and have gone from 12AX7s and 12AT7s to FET/12AU7 cascode with 6DJ8 output, to an all op-amp design... and what I think is 'best' keeps changing. If I can't decide what's best for me, how can I decide what's best for somebody else?
Steve Bench RIAA 5 - I built one of these in the late 90s, still have it today. Fantastic!
Use shield tube sockets on the inputs.
http://diyaudioprojects.com/mirror/members.aol.com/sbench101/Preamps/RIAA5.gif
Use shield tube sockets on the inputs.
http://diyaudioprojects.com/mirror/members.aol.com/sbench101/Preamps/RIAA5.gif
One question is how much gain you're looking for. What sort of cart are you going to feed it with?
The guy has 6dj8 not 12ay7 which aren't too cheap for 4 of them...are the new 12ay7 good?
https://www.thomann.de/ro/tad_12ay7...MIt7T4mqzI-gIVWfZ3Ch3SRAndEAQYAiABEgJKQPD_BwE
Great suggestions thanks everyone, I have enough to look into.
In terms of gain I was thinking 40dB for MM carts. I’ve got a Sowter 9570 and Cinemag 1254 SUTs if I want to use MC
In terms of gain I was thinking 40dB for MM carts. I’ve got a Sowter 9570 and Cinemag 1254 SUTs if I want to use MC
@dreamth The RIAA5 uses 6DJ8 and 12AY7. Both are dual triodes, so only (2) tubes are required.
@itsikhefez SUT are the way to go with MC, particularly when using a tube phono. Both those transformers are fantastic, you have an embarrassment of riches.
🙂
@itsikhefez SUT are the way to go with MC, particularly when using a tube phono. Both those transformers are fantastic, you have an embarrassment of riches.
🙂
I highly recommend the PH16 phono preamp sold assembled or as a kit by Tubes4hifi. Online support available.
I am using mine with a Technics 1200G turntable. I did a lot of parts upgrade during the original build.
The reviews are all stellar. It uses 6922 or equivalent tubes.
I am using mine with a Technics 1200G turntable. I did a lot of parts upgrade during the original build.
The reviews are all stellar. It uses 6922 or equivalent tubes.
Got the Technics tape deck belt fixed. Passed on gear replacement. Dumpster find should remain true to it's dignity of being generous and free. Loving these 70s mix tapes I don't know why I kept. 63 and brings me full circle.
If you want to try SY's "His Masters Noise" phono pre, I still have some boards left and they are sold at cost in respect of Stuart's IP which he graciously donated to DIYAudio. Sounds good to me. $3 plus postage.
Yes that would be amazing. I was reading through his site a few days ago about it and some comments indicated that some parts were obsolete, but I'm sure alternatives can be found