Does my phono stage have sufficient gain?

As always Al, thanks for the education.

Brent

ZYX did not use the industry standard test record when they measured that .24mv output spec. A LO ZYX's output using the industry standard record is ~1.41x higher, so ~.34mv.

Redoing the calculation above for .~34mv yields ~5.7 volts before the power amp inputs, which presumably is sufficient.

Whether the 3 ohm tap on the EAR will provide a suitable impedance for a LO UNIverse is a whole other question. If not, frequency balance in the highs may be off.

More generally, the EAR and Sonic Frontiers phono and line stages are not really capable of reproducing everything a UNIverse will send them. Not saying it won't sound great, it probably will, but be aware that you'll still be missing quite a bit. To that extent this is a slightly risky choice of upgrades.

OTOH, the remaining UNIVerses are such a bargain it's hard to resist, even though upgrading your phono and line amplification before attempting a top tier cartridge would normally be preferable. But top tier phono and line amplification would cost at least 3X the price of a UNIverse, so this might be a good time to break that "rule".

Enjoy!

Thanx, Dougdeacon. Ths impedance issue is a concern. Using the 3 ohm tap on the MC-4 and the stock 47.7K ohm impedance of my phono stage, the load impedance would be about 53 ohms = 47,700/(30^2) - low for the UNIverse. Might not be a good fit.

I appreciate the advice and candor. My Sonic Frontiers phono stage has been completely re-built by Bill Thalmann and the EAR MC-4 is a well-regarded SUT, or at least I thought. While I am fairly pleased with the results of this combo, I will certainly consider your thoughts. My Clearaudio Stradivari was slightly less than the UNIverse, but not by much.

The Sonic Frontiers Line 3 line stage comment did surprise me a bit. I have never had anyone suggest upgrading the Line 3 unless I had $10k plus on hand. I sent it back to Chris Johnson for a comprehensive update and mod using premium parts, so we are not talking a stock, 10 year old unit. Obviously, I like the SF sound and I thought a Line 3 was a well-regarded line stage - able to hold its own with most line stages out there. My "price of admission" to a top-tier line stage was reduced by buying a cream puff unit used and using Chris to mod.

Again, I appreciate your candor.

Brent

It sounds like you might get by with using the 24:1 tap, which would give the ZYX a more favorable (i.e., higher) input impedance. Failing that you can replace the load resistance on the SUT secondary (the 47K resistor in parallel with phono input) with a larger value one. If you go to 100K ohms, your cartridge will see about 100R via the 30:1 taps, which is at least in a better ballpark. (I don't know what is considered ideal for the LO ZYX.) The point is that you have more flexibility than you realize. Any typical amplifier will have an input sensitivity for full output of less than 2V. Of course, there are exceptions.

Brent,
I missed the fact that you've had your SF gear upgraded. Very sorry. Of course I withdraw everything I said about it since I haven't heard yours. Higher quality caps and power supply improvements would, IME with other preamps, make a dramatic difference.

That said, $10K+ is indeed the price of admission to the 2 or 3 best phono/line stages I've heard, and even that doesn't necessarily get you there. Not that you need to spend more, I just meant that I've heard many $10K and even $20K preamps that DON'T get you there. Your buy quality used and upgrade path makes great sense to me.

Unfortunately, with SUT's, about the only way to know if a particular LOMC will mate well is to try. You could always adust impedance with resistors either on the primary, the secondary or both. That's a lengthy process needing many resistors of many types to find the optimal setup. Been there, did that, much prefer the ease and sound quality from my high gain LOMC section. YMMV of course, especially with something as complex as impedance matching with an SUT.