I'm looking for a decent MC phono pre in either kit form or pre assembled for med gain cratiridges. Adjustable subsonic filter would be great as would be cartridge loading. I just want something better than your typical fair op amp design. Any thoughts or ideas?
Salas Ultra. It stands toe-to-toe with any of my other phonostages, and I have quite a few. It’s absolutely wonderful. 🙂
LINK
LINK
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+1 with Salas. I liked the previous simplistic jfet one too.
Hybrid ( jfet+tube) Allen Wright's ( fvp single ended or rtp if differential balanced).
http://www.vacuumstate.com/index.dna?rubrik=8&lang=2&a=%A4i%0E%19%9DO%83z&b=739061.6847868386
I choose Rjm's Phonoclone for my MC ( opamp though). Rjm told the Emerald sound the same with better flexibility ( mm or mc).
https://phonoclone.com/diy-pho4.html
https://phonoclone.com/diy-pho7.html
Hybrid ( jfet+tube) Allen Wright's ( fvp single ended or rtp if differential balanced).
http://www.vacuumstate.com/index.dna?rubrik=8&lang=2&a=%A4i%0E%19%9DO%83z&b=739061.6847868386
I choose Rjm's Phonoclone for my MC ( opamp though). Rjm told the Emerald sound the same with better flexibility ( mm or mc).
https://phonoclone.com/diy-pho4.html
https://phonoclone.com/diy-pho7.html
My (very) old advert for Kora 3T kits is still valid and I do have some kits left. Can do even the Limited Edition MC kit with special FETs and Black Gate caps on the output (only as a fully assembled and tested board + Hammond case).
Cheers
Alex
Cheers
Alex
Hi, The very best MC kit amp is the HypnoToad AD797, as shown on the A/K site, Use Bursions V6 Vivid in the 2nd stage & Connel Dumblier output capacitors. In this form, the unit will outplay any commercial unit up to $5000. It also has adjustable gain & loading. Which makes the unit very versatile.
Available from member Sachin on this site or A/K. Cost to build around $300 including P/S
Yes the Salas is very, very good, but way beyond my ability & gain is fixed.
Cheers
Available from member Sachin on this site or A/K. Cost to build around $300 including P/S
Yes the Salas is very, very good, but way beyond my ability & gain is fixed.
Cheers
The Salas is easy, comes as a kit, and is well supported.
Gain selections are 40/43/56/62dB made with a switch.
Gain selections are 40/43/56/62dB made with a switch.
Hi, The term ''EASY'' depends on your level of electronic skill. I have been dabbling in electronics for 30 years, building several kit's. But the Sala is well beyond my capability. However the OP may well have the skill, if he does, then yes it is the one to go for.
Was not aware that the dB level could be made switchable. Mine (I bought made up) is set at 32db, would love to get a switched gain.
Note that with OP-amp & output capacitor upgrades the AD797 is not that far behind and both are both incredably quiet
Cheers
Was not aware that the dB level could be made switchable. Mine (I bought made up) is set at 32db, would love to get a switched gain.
Note that with OP-amp & output capacitor upgrades the AD797 is not that far behind and both are both incredably quiet
Cheers
Here's the schematic, see the gain switches S9, S10, S11, S12.
If the switches are not on your board, just change the drain resistor.
For 43dB, it should be 2.2k.
If the switches are not on your board, just change the drain resistor.
For 43dB, it should be 2.2k.
Attachments
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Would 40db be a good setting for a MM cart? I'm getting started with a decent turntable with an Ortofon OM20, and want to make one good preamp that can also work well with a future MC setup.
Thank you. Can the gain be reduced any further through the correct choice of drain resistor, like DNic's unit (32db)? It looks like the OM series is rated right at 4mv (1k, 5cm/sec) and I would like a little headroom.
So less than 40dB gain?
You can set the gain as you want with the resistor value, as long as the test DC voltage across R4 is correct.
Check the thread, it should tell you the value. Also looks like you'd have to adjust VR1.
You can set the gain as you want with the resistor value, as long as the test DC voltage across R4 is correct.
Check the thread, it should tell you the value. Also looks like you'd have to adjust VR1.
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Hi, 35 to 37 dB gain is normally to low for a MC cart. but that depends on the carts output. Some go up to 1mv, however the best are normally around 0.2 (or even lower) to 0.3mv, so you will need at least 55 dB gain or more to drive these. But that also depends on how quite your Pre amp is. So more gain in a quite MC Pre normally means less noise into the Pre amp.
The AG797 MC phono amp I mentioned above has adjustable gain via 2 trim pots from about 35dB to 65dB, so it covers all bases.
Cheers
The AG797 MC phono amp I mentioned above has adjustable gain via 2 trim pots from about 35dB to 65dB, so it covers all bases.
Cheers
I didn't build one for MC, but Pete Millett's design, using AD797 chips could be used with a Cenimag SU. Then of course, that could be switched out for use with MM. I do not know the gain this phono amp, but in the MM build that I made, it did well. Also, noise was non-existent.
As it happens, I own a Jolida phono pre that has capabilities for both MM/MC. This is my experience. The gain of this phono amp is so high at 70db, that noise of any kind right there with it. This is true of MM as well, and I have even gone to the extent of using a set of tubes that inherently have less gain, but nope, still too much gain. OTOH, I once built a Glassware phono amp that needs to be used with a preamp which has plenty of gain. These have taught me to be more selective in future decisions. a sort of Goldilocks story to be sure.