CONUNDRUM

Handymann, I think I already responded to another OP that you started about this issue. As previously mentioned, I own an ARC PH-7 and Ref 5. Jfrech's advice is ok, but the PH-7's gain output cannot be adjusted. There are no switches or knobs to do this. As I see it, your "obvious" choices are simple if you are clipping your pre: change the pre, change your phono stage,or change the cartridge.

At one time, I also owned the Maestro. It's may very well be the best MM cartridge on the market today. I'm sure you are not excited to lose it, but a carty is less expensive than a pre or phono stage.

I have two suggestions that you may want to explore for viability. I've never gone down this road, but it be may worth asking. Call Tom Tutay at Transition Audio Design in Florida and ask if he can rig: (1) some type of an attenuator to cool down the PH-7's gain without degradation of the signal to the pre; and/or (2) a SDT (step-down tranny) to reduce the output signal of the Maestro that is fed into the PH-7.

FWIW

Second Swampwalker and Jcarr, but I would still ask ARC and Tom, FWIW.

Addendum: Tom Tutay is very solid. I used him to build a very custom impedance buffer that summed L/R channels and corrected an asymetrical loading problem. That's about as "custom" as it gets. I reiterate my suggestion to call him. Perhaps other folks who know Tom could weigh in with approbations.

Al, I got us off topic, but I'll close the "capacitance" loop fast. Thanks for the info on the Zephyr. To my untrained journeyman ears, the Zephyr souns great, cables and all. I thought the Maestro did too. Something to be said for ignorance -- if I feel happy, then I guess I am. :)

I agree that the primary problem is line stage clipping. Al, do you agree with my suggestions above, particularly those relating to calling Tom Tutay and ARC???

Spencer, As I have already mentioned 3 times, I own the PH-7 and owned at one time the Maestro. By itself, the PH-7 has no problem with the Maestro. The real problem here is that the PH-7 is overloading the line stage and the PH-7 does not provide for gain attenuation.

IMHO, the real solution and the best solution is that the PH-7 -- which btw is a very very good phono stage -- would do a great job with pretty much any carty (except those with outputs less than .5mV) IF the PH-7 was matched with an ARC line stage. The synergy is perfect, as would be expected.

I will not repeat the advice I gave above, other than to say that I would ditch the PH-7 and/or the Maestro as a last resort, of course taking cost/benefit into account. This is a practical problem that demands a practical solution.

One last point. Almarg mentioned in another OP that capacitance may be an important and possibly choice limiting factor when selecting MC carties. As I recall, MC carties are sensitive to aggregate capacitance of the phono stage and I/Cs between the TT and phono stage.

The ARCDB web site reports that the input capacitance of the PH-7 is 200 pF. That may be the upper limit of some MC carties. If so, very low capacitance and short I/Cs would be called for.

I had this problem when using a DV 20Xs H carty. I was using long (12') cheapo Radio Shack I/Cs. The DV didn't sound very good -- almost listless and dull. I bought a shorter pair of custom I/Cs from Tom Tutay (16pF/ft) and the TT/carty combo was much improved after break-in.

I reiterate for the last time that a converation with Tom Tutay may be worthwhile. A call to Calvin at ARC may also be warranted.

Good luck. If Almarg catches this thread, perhaps he can weigh in with better advice.

Thanks Al. BTW you may have picked up on something about the Maestro that that I d/n focus on when I fiddled with it on my VPI Classic. As I reported in many posts to the point of ad nauseum, I had a bass ringing/resonance that Mike at VPI and I could not fix. At the time, Mike and I focused on optimizing the set up to manage the tone arm/carty resonance from a mechanical perspective.

In retrospect, I question outloud now whether there might have been a mismatch with the PH-7 by reason of capcaitance: Maestro - recommended 100pF vs. PH-7 - 200pF (not even including I/Cs of another 100pF).

I think this point is relevant to the OP because he has the same front end as I did. Any thoughts??

As an aside, I currently use a SS VPI Zephyr, a MI carty. I checked the SS web site. FWIW, nothing mentioned about capacitance that I could find????? Oh, the Zephyr sounds great to my shriveled ears.

Elevick, the PH-7, if modified by ARC, has 6 tubes: (4) 6922 tubes in the gain circuit; and (1) 6H30 tube and (1) 5881 tube in the PS. I don't think your idea has legs.

Handymann, the Koetsu is a very expensive cartridge, most models are in excess of $4K. Not sure, but there appears to be several Urushi models. Based on a very high-level check on the Needle Doctor web site, it appears the output voltages range between .2mV and .6mV. This class of cartridge appears to have a low compliance factor of 5.

Clearly, the Koetsu generates much less voltage than the Maestro. Therefore the PH-7's output should be less too.

If you want to try a LOMC, perhaps it would be prudent to try a cheap LOMC and see how it works. As I mentioned above, the PH-7 has a noise rating of 70db. It would be very unfortunate if the PH-7's output put out alot of noise with low output carty. I reiterate, it's worth a 15 min call to Calvin at ARC. He's in the best position to advise you.