Step up transformer for Benz Ebony TR cartridge
Your
RCM Sensor Prelude phonostage which has a gain of 76 db should be more than adequate. I'm using 72 db setting with my Ruby P1 phono and no SUT needed http://www.wyetechlabs.com/preamps/phono/phono.html |
Dailycitrus, Congrats! It's a really superb SUT at a reasonable price. It made a significant improvement on the VAC Renaissance III's phono stage (which had a Lundahl MC SUT built-in), and now that I'm getting more used to the sonic signature of the Eddie Current Transcription, it makes a nice improvement in detail and refinement there too (here it replaces the built-in Cinemag 3440). I've been using 0.5m RCA Audioquest Colorado (copper) that I'd had lying around. Haven't compared to other cables in this position, but it works well. Just make sure you use something shielded. The rest of my system is all AQ silver; I generally find it cleaner and more detailed than copper without sounding bright/analytical. Would like to have silver here too, but I've used all the cash towards a new 'table. Might try swapping the Colorado and the 1m AQ Sky I've got downstream. Were I in your position, I'd consider the Bob's silver cable too, though I've not heard it. The AQ prices keep getting more ludicrous. Mike |
Mulveling, Talked to a few experts, read several reviews and exchanged emails with Bob; I ordered 1 Cinemag 1131 today. Thanks for that reference. Also, what cables are you using from the TT to the SUT and from the SUT to the Pre-Amp? I am considering Bob's silver 1m for the TT to the SUT. I will compare the Cinemag to the Lyra when it arrives. |
Garth Leerer of Musical Surroundings just commented on a Paul Seydor MC cartridge survey in the April issue of TAS. Leere pointed out that the phonosatge used for the survey has a transformer-coupled input stage. Both the Benz and Clearaudio cartridges have high coil-impedances and preform at their best with high-gain phonostages. I'd email the importer for a more substantial recommendation. |
Thanks for the detailed in put. Your response, which is much more detailed that I can be, is much appreciated and unfortunately what i expected. The dealer is still checking but I think if I want to hang with a Benz and keep my Lyra i will have to settle for the L. the Lyra has a SUT ratio of 20:1 / 26dB and as you suspected the phono input impedance is 47k and 2MV sensitivity (vintage McIntosh C22). |
I'd look for a SUT with a step-up ratio of at least 40:1. That'll yield 32dB of gain, and the cartridge will see a load of 29 ohms (assuming the SUT is hooked into a 47K input). That should be sufficient; the loading would be analogous to that of a typical 5 ohm MC seeing 150 ohms, which is fine. A 0.1mV output is 9.5dB below 0.3mV, so you'd probably want at least 72dB overall phono gain (i.e. a 40:1 SUT plus an MM stage with at least 40 dB). The Bob's devices Cinemag 1131 sounds excellent and offers a 40:1 ratio -- I'm currently using the 20:1 "low" setting with with my 0.3mV, 5ohm Koetsu. Actually, in my current system w/ 48dB MM phono, 20+dB preamp, and sensitive amp & speakers, I have quite a surplus of gain -- verging on too much. The Ebony TR would probably be a lovely drop-in! The Benz carts I've heard (none from the newer S class though, and only as high as the Reference 3) have all been very enjoyable; definitely nothing that should remind you of CD sound. You might also want to investigate Koetsu; so far that's been my ultimate destination in the search for resolving & enjoyable sound across all genres, and including less-than-stellar recordings. |
Your RCM has a lot of gain options, which is very nice. That raises the question of how much gain to get from a SUT versus your RCM. A 34 dB gain would mean you end up with something like 35 or dB gain on the RCM. Is it better to have a large SUT gain versus a larger phono stage gain? I am not a SUT guy, just asking the questions after looking at the wide range of gains available for SUTs. |
Thanks Syntax for the advice. I have two questions here: 1. Whether it is Cotter or Fidelity research, is it enough to just see the gain amount (e.g 1:20) or do I have to see any other spec so as to make sure the SUT is compatible with my cartridge. For example, one of the SUT manufacturer wrote back to me that the 1 ohm output impedance of Ebony TR is a special case and so he will have custom make an SUT for me. So, is there really something special about a 1ohm output impedance as far as matching an SUT is concerned ? 2. Would you be able to give any specific model numbers of Cotter or FR to look for, or are you saying that any model from these manufacturer is good enough? |
I want to keep it within $700. Any suggestions please ? Some years ago I tried different SUT's from well known Manufacturers and - honestly - most were bad, the best from them maybe average. The majority colors the sound (based on their average specs), a "blind" selection is like rolling a dice. Super (= accurate) SUT's are hardly used in High End audio, they are very expensive and destroy every profit and when the customer buys a "Black Box" Anyway ... Maybe the old Fidelity Research units will give a good result (they do) or a Cotter unit. Analog reproduction is a chain, to amplify a 0.10mV cartridge for 100% is a task. 0.25mV or 0.30mV is also low, but much easier to handle. |
Bluewolf, that preamp of yours seems absolutely esoteric!! No wonder it will suit amazingly well the Ebony TR. Please do write here what you think about it. In the mean time, I confirmed with the manufacturer of my phonostage (RCM Audio) and they said the Ebony TR is meant to be used with a SUT, the TR = Transformer. Also they said that my phonostage has roughly about 66db of gain for the full spectrum. The 76db spec is taken at 1khz and in that state there is a possibility of signal loss in the frequency extremes. Moreover the output impedance of the Ebony TR is only 1 ohm which is not a good case for the active phonostage. In this scenario I have to seriously look out for a decent SUT which doesnt cost much yet does justice to an expensive cart like the Ebony TR. I was looking at the Bob's devices, Silvercore and Dave Slagle (Intact Audio) products. I want to keep it within $700. Any suggestions please ? |
I have an Ebony TR (not the S) and it has .2mV output. I use it will a Linn Linto with 62.5dB gain and it is fine with that amplification. I believe that the newer S drops to .1mV. Rest of the system is Cary SLP 05 and Levinson 432. I have the Cary attenuate the signal since the signal from the Linto is pretty strong. The LP is the top of the line Benz. It has a .35mV output. Either should work with a good quality 60 dB phono stage. KAP USA has a gain calculator for phono stages Gain Calculator |
Pani, I have a brand new TR which I hope to get up and running in a few weeks. From what I have read you need a step-up transformer to get the most out of this cartridge, and good ones are very hard to find. I would go for the Syntax. Contact either Dertonarm or Unoear, both on Audiogon, to see if they have one left. This is a custom step-up transformer that comes highly recommended by some very good ears. I hope this helps, |
