Hi All!
As a followup to my Heybrook cartridge thread, I would really like to hear your opinions on what to do about phono pre-amplification. I mentioned in my Welcome post that I have a Sony TA-E86B preamp with on-board MM and MC phono stage (info here: http://www.thevintageknob.org/sony-TA-E86B.html Click on the User link at bottom left of the page for a review). I am presently using this in my main system together with a modded Teac VRDS-10 cd player and Belles OCM 200 power amp. Some years ago the preamp was modified to become a passive device for the line stage section, which really lifted a veil from the music, as the saying goes.
This mod left the phono amp intact, but with the consequence that the phono stage no longer benefits from the added gain of the main preamp section. As a result, any turntable has insufficient gain to really drive the power amp and speakers. It can get to a reasonable volume, but the attenuator has to go to 11 to get there...not good. I suppose if I got a higher output MM, like a 6.5mV Goldring, it would have more drive than the 4mV Shure I’ve tried with the Sony so far, but it would probably still be anaemic.
So now that I’m adding a good phono source (the Heybrook), I need to do something about this. The way I see it, I have three options here:
Option 1 – Reverse the Sony mod, and then recap the thing to get better sound than pre-mod. This is the path of least cost, esp. if I do the work myself. The big question is: will the sound quality, even with the recap, be better or at least equal to Options 2 and 3, below? Further, as a passive line device, the Sony sounds great – very clear and detailed -- but will I be able to maintain that transparency even with a high quality recap?...that’s an unknown. Any recap I do would include the phono stage. On the plus side, the Sony has a MC head amp, and in total there are five input impedance choices – 100k, 50k, 25k, 40, and 3 ohms – so there is some versatility here. According to the review linked above, the phono stage is of high quality, but that review is decades old, so I’m not sure how relevant it is by today’s standards.
Option 2 – Buy a separate phono preamp. If well chosen, this is potentially the path of best sound quality (your opinion needed here), and moderate cost. I am also not averse to building a kit, and it looks like there are a few good ones out there which should be simple to build. If I go with this option, I would get one with MM and MC capability, as well as switchable impedance and capacitance. Not sure if a kit could do that, but there seem to be some good off the shelf models that have this flexibility. A well-designed tube preamp would be in the running here too.
Option 3 – buy a whole new preamp with line inputs and phono stage. This is the path of highest cost, but perhaps least flexibility to fine tune the phono input for impedance, etc.. The big advantage here is that the line input components (CD player and tuner) will get the added benefit of a gain boost and even more oomph to drive the speakers (same as Option 1, but with a modern circuit). The CD player really doesn’t need the boost, as it’s pretty dynamic after the clock and op-amp mods, but it wouldn’t hurt. My fear is that I may lose the transparency I’m getting now with the Sony as a passive device, but diligent auditioning should weed out the bad ones. Belles makes a nice Aria preamp that looks appealing, for reasonable money, and I would have confidence buying another Belles product any day. Higher cost and lack of flexible phono input adjustment are the deterrent here.
I suppose Option 4 might be to buy a separate phono amp plus a new active line stage preamp (the best of both worlds?), but that could get costly and maybe not necessary(?).
So there you have it. I’m curious to hear your thoughts and experience with this, and your recommendations. Most important, obviously, is good sound quality, followed by reasonable cost. In your experience do separate phono preamps provide better sound than on-board phono stages? Is this pretty much universally true (ignoring the cheapo bottom end models)?
Another fundamental question, beyond the phono preamp thing, is whether active line and therefore downstream phono preamplification better than a passive device? I've read little about this question...interested to hear your opinions.
Looking forward to hearing some feedback.
Thanks in advance, and regards.
Svend