KOETSU VERMILION and audio research PH7

I did not say, nor did I intend to say, that using a SUT is a bad idea.  I only say that using a SUT with the PH7 would probably be a bad idea.  Because it would likely overload the PH7 resulting in distortion, and because the PH7 at the very least would need to be modified to present a 47K ohm input load resistance, if it doesn't already come so equipped.  Using a SUT with a high quality MM stage might be fine.  Another factor that has been excluded from this discussion is the additional gain, if any, provided by the OP's linestage.  Most linestages add 10db to 20db of additional gain, unless one is using a passive stage. So, mulveling, when you got your mediocre results with 0.3mV cartridges, what was your linestage gain?  I ask, but I don't want to be in the position of insisting that 58db of phono gain is "OK' with an 0.2mV cartridge.  I do agree that more gain is better in this case.

@lewm
At one time I was using that Sonic Frontiers with a Hera II linestage that had gobs of gain (over 20dB, much more gain than the 15dB specd for the Hera I), and it didn’t help pull the dynamics back. Plus very high gain tube amps (over 36dB) and 96 dB / Watt speakers - I wasn’t wanting for gain in the overall system. It could get really really loud, and had a lovely midrange and treble, it was just sad and lifeless with no bass impact. The Koetsu Platinums came to life with any of the other phono stages I listed. I also used the SF in a high end Stax headphone setup (009, T2) with SOTA Nova, and same conclusions with same set of cartridges.

I agree with you, I wouldn’t ever try a SUT with either the Sonic Frontiers or the PH-7. Just the wrong configuration for that.

Check if there is any gain on your line pre-amp.  Most are flat but some have 10 or 12 dB of gain.

So I guess the output of your phono stage was just not sufficient to drive the Hera linestage for it in turn to produce enough signal voltage to drive your amplifier.  (The results are dependent upon the input sensitivities of each of the components in the chain, not merely their respective capacities to add gain, as I am sure you know but just for others to benefit.)  Clearthink, I beg to differ a little with what you say; most active linestages do add gain, typically 10db to 20db.  Unless one is using a passive attenuator, there will be some added gain from the linestage.  I'm not saying this is a good thing, necessarily; it's just most common in my experience of looking at specs.  A few phono stages that offer the option of being used as full function preamplifiers do use only a cathode follower in the linestage section, which adds no gain but permits the linestage functions, like introduction of a volume control and switching of CDPs, etc.  My Manley Steelhead is like that.

Is there any big diiference between the 0.2mv from VERMILION and the 0.24 from ZYX ? because as It seems, Koetsu do not mesure their voltage at 3.5cm/sec , and for my PH7 the voltage of ZYX 0.24 works very fine.