almarg, I'd be interested in knowing if you have any favorites in the phono preamp category, care to comment?
Audio Research PH5 Phono Preamplifier Input Clipping Problem
I have an ARC PH5 phono preamplifier and most of the time it sounds fine. But on a few of my favorite LP's with wide dynamic range, it will clip and distort on loud sections, especially those with lots of bass content. This only happens with use of a step-up transformer, without the SUT in line, there is no clipping. I do prefer to use the SUT, as without it I have to turn the volume setting on my ARC REF 3 preamp to a very high level. I have to conclude that the PH5 is distorting because of high input signal levels, due to the gain of the SUT. I have tried two SUT's, one with 13:1 and the other at 7:1, both exhibit the same problem (although the lower gain SUT is much better). The cartridge is Ortofon A90 with .27 mv output. Given this, would you expect clipping or do you think there is something wrong with the PH5? I have talked to ARC about this issue, and they seem to think that there is a chance the PH5's maximum input of 70 mv is being reached on these loud sections. Would appreciate opinions from those that have experience with a similar setup. Thanks.
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Scott, yes, inspired by a great many overwhelmingly positive comments I've seen here and elsewhere, late last year I purchased a Herron VTPH-2 phono stage ($3650). It is beautiful sounding, versatile, very intelligently engineered, absolutely quiet at any volume setting in my system in both LOMC and MM modes, and as many others have commented Keith Herron is a treasure to deal with. It is offered in a choice of two gain configurations. For the majority of applications, including mine, the lower gain version is preferable. It provides gains of 43 db in MM mode and 64 db in MC mode. The one slight caveat I would cite is that like your PH5 it does not provide balanced outputs, and John Atkinson's measurements of the REF3 indicate somewhat better measured performance in balanced mode than in unbalanced mode. But even if those measured differences have any audible significance, which I doubt, I would suspect they are mainly attributable to JA having used the preamp's unbalanced outputs for the unbalanced measurements, not just the unbalanced inputs. And I note the following statement in the body of the review: ARC states that the long-tailed pair used in the Ref.3's input stage provides identical performance (save for the amount of gain) using either the balanced or the single-ended inputs.Good luck. Best regards, -- Al |
Yes I have noticed that one is recommended a lot. Looks like a move from PH-5 to Herron could cost about $ 2K. Will have to consider whether that is "reasonable" or not. But for me, swapping gear and upgrading is part of the fun. It seems that used versions of the Herron are hard to find. I guess those who have them, keep them. Did you purchase yours new? |
Yes, I purchased my VTPH-2 new, directly from Keith after speaking with him on the phone. You would want to confirm with him that the lower gain version is the optimal choice for use with a 0.27 mv cartridge. I suspect that it will be, though, in part because he recommended that version for use with a 0.3 mv cartridge I was considering at the time. I ended up going with an Audio Technica AT-ART9, though, which is rated at 0.5 mv. Best regards, -- Al |
This has two gain settings. Take a look, it just might fit the bill ! https://www.youtube.com/watch?v=RfpJYJv3ddo |
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