Fidelity Research FRT-4 and Entre ET-100 step-up transformer SUT comparison


These two vintage step-up transformers are often mentioned together along with Denon AU-340 as the ones to consider if you're running multiple turntables and tonearms like myself. I have the Fidelity Research FRT-4 and Entre ET-100 and here's a quick summary of my experience between the two. I'm unaware of any current SUT offerings that allow for multiple inputs and multiple impedance selections, let me know if there's one out there.

The Fidelity Research FRT-4 boosts my LOMC signal without any negative side effects that I'm able to hear. Background noise is now almost non-existence, I'm hearing so much more air and natural extension on the top end from both of my LOMC's. Vocals just float in the air with beautiful imaging, an experience I hadn't had before adding this SUT into my system. Overall, this SUT sounds clean, clear, and punchy with just the right amount of meat on the bones for a balanced organic sound. 

The Entre ET-100 is a tad more laid-back-sounding compared to the FRT-4, the background noise is just as low with no negative side effect that I can hear. In my system, the top end doesn't sound as open and airy as the FRT-4. I love the way this SUT sounds with my jazz recordings, especially the few with a little more bite on the top end, the sound is more easygoing with this one. Build quality is just as good if not a little better than the FRT-4, and it's a little larger than FRT-4 which I was surprised by. The knobs feel smooth and sturdy with both of these units and I'm able to switch from one turntable to another without any noisy static through the speakers.

FWIW, the ET-100 allows you to use output cables of your choice, whereas FRT-4 has existing output cables. If there's a current SUT out there with all of these functions, it would garner much more than the price these two models are going for. I hope this helps someone who's considering between these two excellent SUT's.

128x128scar972

All of the FRT4 I’ve seen in pictures have output leads consistent with mine. I haven’t peaked under the hood to see if mine has the 18K resistor. Do you know if the 18K resistor is a mod or a part of the original design?

I believe what you guys say, but see photos here.

https://www.google.com/search?q=fidelity%20research%20frt4%20review&ie=utf-8&oe=utf-8&client=firefox-b-1-m

In the review I read, the reviewer said he found the 18K resistor when he opened the chassis. So it seems he did not install it. He also posted a schematic that it seems he drew up based on what he observed. It’s not entirely a crazy idea. If you have a low output, moving coil cartridge with an internal resistance of less than 10 ohms and if you want it to be loaded with approximately 100 ohms, and if you are using a one to 10 step up ratio, then the addition of the 18 K resistor results in the cartridge seeing a 130 ohm load which works just fine. Where you could get into an issue is if you use a low output cartridge with a higher internal resistance.

Dear @scar972: " top end doesn't sound as open and airy as the FRT-4 "

 

Look that output lead is  and advantage only with today better IC cable but in your case is not and that " open and airy " in reality is only developed distortions.

I still own the Entré ( I owned over 15+ different SUT. ) and owned the FR and at least according my reproduction MUSIC targets the Entré 100 is superior to the FR.

 

Regards and enjoy the MUSIC NOT DISTORTIONS,

R.

 

 

Raul is on the record(!) as saying he disapproves of us being subjective and choosing what we like.