Do I Need A SUT


I recently moved from a PS Audio BHK Reference pre amp to an LTA ZTOL pre amp.  I found the LTA pre amp to be more detailed slightly warmer and it just sounded better in my system.  I also noticed a big difference in the output volumes between my digital rig and my analog rig. At the same volume level, my turntable volume is now much lower than my streamer volume, as opposed to the way it was before.

Analog gear - Technics SL-1200G turntable w/ Ortofon Quintet Black cartridge and PS Audio Stellar phono pre.  Digital gear: Innous Zenith MK2, Matrix DDC, and PS Audio DirectStream DAC MK2.  Power amp: PS Audio BHK250.  Speakers: Tannoy DC8-Ti.

Before, I used all Transparent Super XLR balanced interconnects, except for the turntable RCA cable into the phono pre.  Now, the only balanced cable is from my DAC to the ZTOL, which has only one XLR input.  I replaced my Transparent XLR interconnects with Transparent super RCA interconnects.

Do I need a SUT to get a higher level of sound at a lower volume setting?  My budget is $1,500.  I know nothing about SUTs other than what I've read. I'm considering the Ortofon ST-7.  Recommendations welcomed.

128x128oldschool1948

You only need an SUT when your phono stage lacks enough gain for a LOMC cartridge.

OK, so I don't need a SUT 😁!

@lewm @jasonbourne71 Of the three gain levels on the Stellar, my system sounds best at the lower setting, which is the recommended setting for the LOMC Cadenza Black. The other two don't sound as smooth. I've also used Stellar's custom loading option set at 30Hz, but finally settled on 60Hz. 

@mashif I'm going to try the all RCA route, which should reduce the DSD output a bit.  I've been playing the DAC at 90% volume level for years. If necessary, I'll futz with that some more to get the two a little closer together. 

Regarding LTA, you are correct. I live about 45 minutes from their office. It's always a pleasure going their - everyone is very nice, very accommodating, and fun to be around. Nicholas has been very accommodating, allowing me to home audition their preamps and power amps. I'm looking to audition their new DAC soon.

Thanks everyone for your help!

I am guessing you meant you’re setting the input impedance of the Stellar at 60 ohms, not 60 Hz. Also, I think the LTA is a single-ended device, so no matter what inputs or outputs you use going in to the LTA, the signal out of the LTA is SE

@lewm You are correct on all accounts!

I replaced the DAC’s Transparent Super XLR cables with Kimber Select KS 1010 RCA cables. I use the Kimber cables on my R2R. The sound with the Kimber cables is noticeably better.  

I left the DAC volume at 90%, and tried various Stellar gain and input impedance combinations. The best combination was gain at medium and impedance at 200ohms. That same combination didn’t work as well with my BHK pre amp and Transparent XLR cable.

Now, both the turntable and DAC sound about equal in volume using the same LTA pre amp volume setting. Tomorrow, I’m going to put the Transparent XLR cable back on the DAC to see how much of change that will make.  

There is no particular reason to worry that the attenuators need to be set differently for analog vs digital, unless you’re prone to forget to turn down the volume before switching from analog to digital and fear speaker damage. Otherwise I personally set up analog gain for max SQ regardless of high level inputs.