SUT Info

by elliottbnewcombjr on

Description

SUT Info I have gathered.

My Fidelity Research FRT-4

https://darklanternforowen.wordpress.com/2021/01/01/fidelity-research-frt-4-mc-cartridge-transformer/
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Components Toggle details

    • Fidelity Research FRT-4 SUT
    Pass for MM, 4 optional impedance settings for MC, 3 tonearms, front selectable

Comments 9

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Owner
Happy Holidays to you!

Thanks, good to have your comparison notes. I knew about but have not heard an Entre ET-100, and I see a unique variant ET-100-2 listed occasionally, not sure if the innards are different or just naming the 3 inputs differently. This listing shows a lot:

https://www.ebay.com/itm/266643542021?mkevt=1&mkcid=1&mkrid=711-53200-19255-0&campid=5338381866&toolid=10001&customid=fb77029c-c479-11ef-9362-316264373137


Output: Phono Cable/Ground Wire and SUT Location Comments:

Fidelity Research FRT-4 has a captive output cable (rca with ground) terminating with RCA Plugs and loose ground wire. The Entre ET-100 has RCA Jacks out and a Ground Terminal, so you need and can use your choice of Phono Cable. I sometimes think of modifying my FRT-4's output cable, but it sounds great, so no need. 

I did have to extend my FRT-4's ground cable at the preamp end, because the ground terminal on my McIntosh mx110z tube tuner/preamp is on one end, far away from the phono input jacks at the other end.

Attaching the 3 separate ground wires of the 3 tonearms to the one common input ground post on the sut can be awkward, depending on where you place the SUT. 

It was easy, but I moved my SUT under my TT, I can just see/change it from the side. I need to move my separate cab't with amp and preamp, make a good firm connection, and reposition if I change anything. Not ideal when trying a friend's part (TT/arm/cartridge/mc phono stage) thru my SUT's PASS which then retains comparison to two of my arms.

elliottbnewcombjr

@elliottbnewcombjr Another vintage SUT often mentioned along with this FRT-4 is the Entre ET-100. Both have 3 inputs for those running multiple turntables/tonearms and multiple impedance selection.
I've been listening to the Entre ET-100 for the last three weeks, and it's also a very impressive SUT. It's a tad more laid-back-sounding than the FRT-4, and the background noise is just as low. In my system, the top end doesn't sound as open as the FRT-4 but may be more balanced from top to bottom. Build quality is just as good if not a little better than the FRT-4 IMO. I hope this helps someone who's considering these two SUT's.

scar972

Owner
I'm glad it worked out so well for you. It works for all my cartridges, and so far works for friends cartridges we listen to here. I got lucky when I chose it, and it's one of the items like my McIntosh mx110z tune tuner/preamp that I would simply replace without hesitation, not even bother researching anything else, just find another one. Separate control of gain and impedances would be nice, I simply make sure the specs of a cartridge work with it's 4 inter-related options.

elliottbnewcombjr

@elliottbnewcombjr you weren't kidding when you said just "magic" signal boost. I'm hearing so much more air and natural extension on the top end from both of my LOMC. Vocals just float in the air with this SUT...I'm loving it! I also really appreciate the multiple inputs and impedance/gain selector it has, such an audio bargain in this day! I'm questioning why I lived without a SUT for the last 15 years.

scar972

Thank you for sharing, I have an FRT-4 on the way.

scar972

Owner
I do not think the SUT does anything sonically, just 'magic' passive signal boost. My FRT-4 is totally noiseless, and I use PASS to play MM Cartridges I am very familiar with goint directly to MM Phono Input in the past. If your Phono LOMC input (which is/has a SUT within prior to riaa eq) makes some noise, and your MM Phono has no noise, the FRT-4  will let you send your LOMC to your MM Phono with no added noise.

Changing to the various x-factors/resultant impedances, the volume change is instantly evident, after you adjust the volume, listening for slight variations, they are not immediately obvious.

Changing inputs, listening to different cartridges: Stereo MM/Stereo MC/Mono MM/Mono MC (mine or my friends), you can hear differences, and after you take the time to play a lot of familiar music, you more readily identify your 'preferences' (not better, just preferred).

elliottbnewcombjr

Both of my cartridges are LOMC with outputs of approximately .25mV.
I’d like to see if adding a SUT in front will lower the noise and sound better than going straight into the MC input. Do you think the FRT-4 inject any sound signature of its own to the signal?

scar972

Owner
It is my one and only SUT experience, I feel lucky I chose it (based on it's optional features). Absolutely noiselessly pre-pre amp's the delicate phono signal. PASS for MM. 

Ideally, separate control of x-factor (signal boost) and loading (impedance) is desired, however I am unwilling to spend the amount of money that requires. The FR-4 has a limited set (4) of inter-related options that work well for me and many MC cartridges, but you need to learn and then do the math when pairing it with a specific MC Cartridge.

Actually, it is:

'TRY' a low signal strength cartridge (Moving Coil), and you 
'USE' a SUT to be able to do that. Passive Signal Boost: Magic?

In the beginning, when I was young, ANY and ALL MC Cartridge's made noise! NYET! It was a club for Masochists, Jag V12 Owners, JVC TT-101 and TT-801 Owners

After joining Audiogon in 2019, I decided to finally try a LOMC Cartridge. I got help, followed with research, made some new friends with MC/SUT experiences, decide to go for a long arm at the same time, that led to a larger plinth that led to multiple arms, ...... 

I am a huge advocate for two tonearms, and a SUT (or phono stage) with multiple and easily selectable inputs is a key ingredient for ease of use.

One day I might change the FRT-4's output cable to one with better connectors, and yet 5 years of happy listening ...... 

elliottbnewcombjr

@elliottbnewcombjr I have always wanted to try a SUT but have never had the need for one.  Curiosity is real!
This FRT-4 is one of the models that interest me due to the multiple inputs. Would you share your experience with this SUT?

scar972

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