Croft 25R (with Grant Fidelity/Shuguang 12AX7LS black tubes.) Minimalist MM only.
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I use this Quicksilver. You can find it used for under 1 grand! http://quicksilveraudio.com/products/phono-preamp/ |
@br3098 Any chance of a photo(s) of the interior of your PAB Croft. I spoke to Pear Audio about these units and apart from a wood facia, the weren't very forthcoming on internal ungrades. Seem they are asking a lot more than Croft does. Curious to see what they do. I have the tube regulated version. Thanks. |
Why tube? High voltage rails == high dynamic range with lowered distortion, compared to low voltage solid state. Yah gotta hear it and be looking for it, but it is there, in most tube based phono stages. Less coloration and distortion under very broad dynamics of loading. Octal tubes can do even better here. For the perfectionist seeking tonally correct un-shifted life-like dynamics.... there is but one phono and it’s name is tubes. Mostly true. The odd solid state phono preamp uses high(er) voltage rails. But that is just part of it, as is per usual. No perfect answer, just a noticeable direction. |
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Normally I would weigh in ++++++ as an owner of a Croft RIAA - RS single chassis wonder... but having two USA techs work on it and having sent it across the pond to Glenn himself ( who btw was and is an absolute PRINCE about diagnosis and repair ( dead FET ), and now have a strange HF noise in L channel.... and swapping in complete set tubes one by one to replace the set I got from Andy.... has me drinking and pulling out hair..... having said that my brand spanking new Nova II had a fastener rolling around loose inside.... analog is pain |
rsf507, I see, Nicosia is a divided city but a very old city, a lot of history there. Many apparently great tube phono stages. I would almost certainly be buying used and not very soon. I am in fact trying to figure out what my totally new system should be, so this is not about upgrade in a usual sense. This phono stage should hopefully last me for at least ten years, and $1k-$2k more or less for it would make no difference to me under the |
By the way, XLR ouput would be a plus because I am going to make recordings to reel to reel tape deck, and the good ones come only with XLR ins/outs. @inna If you are going to drive your tape machine XLR inputs, you are going to need more guts! There isn't a single 'high end audio' phono preamp that can drive them directly (without bass loss and increased distortion)! You'll need a line stage that is designed to support the balanced standard or at the very least, a line transformer to go from the phono stage to the line level of the XLR input. We did solve the transformer issue some years ago BTW... |
Any chance of a photo(s) of the interior of your PAB Croft.noromance, I will do so as soon as I can. I painted the living room last weekend and have everything packed away. Now it's a rush to restore the room before Thursday. I used to be a dealer for Pear Audio, and I did once do a side-by-side comparison of the PAB Classic Phono to the Croft RIAA phono stage. The board and parts were quite different, as I recall. |
Eastern Electric Minimax. I have been using one for almost 10 years, Amperex 12AX7 or Mullard 12AX7 as the driver and GE12AX7 or EICO (Amperex made for EICO) 12AX7s for the buffer tubes interchangeably for the 10 years without any issues. No discernible noise at all without music playing, incredibly dynamic and transparent. MM and MC. I have no idea how it can be bettered and why I would bother. |
@br3098 That would be awesome. Croft tends to use good but not great parts. IN4007s and RIFA caps. Due to the microscopic point- to-point handwiring, it’s not too easy to upgrade parts. And I have been there - replaced all the resistors in a Micro back in the 80s with Holcos which, to my amazement, took it to a new level. |
It appears that pro tape machines were not quite designed to take the signal from phono. Well then I would have to use a transformer, what else can I do ?Pro audio tape machines tend to have lower impedance inputs, and often needing some voltage at the same time. +4dbm is common. This is because they are usually driven by a mixer rather than a consumer line source like a tuner or phono preamp. Such sources are usually run through the mixer in a recording studio. The reason for all this is so that the interconnect cables don't play some sort of sonic havoc with the signal. Its not just that its balanced- its also low impedance. However, since we (Atma-Sphere) started this whole balanced operation thing in high end audio, we didn't think that we could get away with making a balanced product that didn't support that balanced standards used in the studio, so we supported it. So one way to use what ever phono section you want is with one of our line sections. Or you can have our phono section added to that line stage. Otherwise you're going to find that a line transformer that can go from a higher impedance down to 600 ohms is mandatory- and since you are going to be stepping down, the output voltage will be reduced. But you might have enough gain that the latter isn't a problem- you'll have to try it and see. When I was first designing our preamps, I had an Ampex 351-2 tape machine in my living room and I found that I either had to modify the tape electronics or use my preamp line section to drive the line level inputs for recording. That's how my Otari and my Studer behave also. Your plan B is to run the output of the phono section into the microphone inputs, but as you can imagine that's not ideal either. Mic inputs are often lower impedance than line inputs (my Neumann microphones are set up to drive 150 ohms). But some machines can handle a 'high impedance' microphone input, although usually you see that sort of thing on consumer decks, not pro audio. So this might still require a transformer, but it would solve the potential gain issue caused by the step-down of the transformer. |
Ralph, thank you, I get the picture. Having your preamp with phono would be an excellent choice indeed. I hope it is versatile enough to work well with various power amps, tube hybrid or transistors. Or, how about this ? MP3 preamp into Gryphon Diablo integrated. Diablo has passive preamp. Why would I want it ? Well, if I decided to have, temporarily or permanently, solid state power amp my choice would be Gryphon, but I wouldn't be able to afford Gryphon power amp even used. So basically I would want just the power amp section of the Diablo, or older Callisto and Atilla. I took a look, Gryphon's input impedance is 10 kohm RCA and 40 kohm XLR. |
I would think that 55db gain is way too high for most or all MM and MI cartridges. Usually it’s around 40db ? But maybe Ralph’s preamps can be customized to change the gain. I am a little surprised than no-one mentioned Lamm and VAC so far, though I am not sure that VAC makes separate phono, perhaps that’s why. What about Conrad Johnson, CAT, some other European companies ? Japanese like Wavac, Komuro ? |
