Audio Note M1 RIAA arrives today... let the SUT wars begin!

And for second-hand ones:
Slightly Used Transformer

 

SUT may be a future step for me if I stay with the AT F-7, so I am reading with interest. What you are describing sounds like gain. Glad it is working out!

 

Have you tried the SUT into the MM input of your old phono stage...assuming it has one.

 

I'm more of an active phono stage guy so my SUT experience is limited, but did have a Fidelity Research transformer in the past and also an active MC pre-pre like the Ortofon mentioned, but perhaps someone could clarify something for me?

Many of these vintage step-ups (and perhaps more modern ones as well for all I know), my old FR included, had either fixed or selectable settings with respect to impedance. My FR, for example had two settings, one at 10 ohms and one at 30 ohms. Surely this can not be the actual load? I was under the impression that this setting related more to the internal impedance of the cartridge in use in terms of properly matching it to the SUT.

In other words, with something like the Ortofon MCA-10 with a 10 ohm "impedance" you would want to match that up with a fairly low impedance cartridge (say something in the 5-15 ohm range like the DV20x2L) as opposed to something with a higher internal impedance like the Denon 103 with 40 ohms, which would be better matched with a transformer or pre-pre with something like a 30 or 40 ohm setting (I believe the Denon SUT designed specifically for the 103 is indeed a "40 ohm" transformer for lack of a better description).

If this is the case then the MCA-10, regardless of it being an active device, would seem to be a pretty good match up with the Dynavector.

Thoughts, anyone?

 

It's definitely not just gain, although with this cartridge, the extra bit of gain with this old head-amp certainly helps.
Also, I found these specs for the MCA-10:

Specifications:
Manufacturer: Ortofon, Denmark
Frequency response: (idling) source impedance > = 3 ohms: 3.5 Hz to 900 kHz - 3 dB
Frequency response: (completed with 300 pF) source impedance: > = 3 ohms: 3.5 to 400 kHz - 3 dB
Frequency response: (completed with 300 pF) source impedance: > = 3 ohms: 7 Hz to 200 kHz + 0/- 1 dB
Distortion over all (at 70 mV output voltage): < 0.1%
Input impedance: 11 ohms
Max. input voltage: 6 mV
Voltage amplification at 3 ohms source impedance: 33 dB
Output voltage with MC 10: 1 mV/cm/s
Output impedance: 675 ohms
Recommended completion: 47 kohms
Minimum completion: 10 kohms
SNR (unweighted) (MC 10, 10 cm/s): > 66 dB
Power supply: 2 x 1.5 V batteries, type IEC LR 14 (alkaline)
Battery life: approx. 800 h
Weight: 650 g

So is it loading the DV20x2L at 675 or 11 Ohms?

 

My previous stage didn't have MM-only inputs, but I didn't try it regardless.

 

Also, in my mind, good active-stages or SUTs should basically do their job without coloration and let all the goodness of one's MM phono stage shine through.

So what I'm really hearing is my phono stage, no?

 

Just a guess, but I don't think it's loading it anything close to those values. I would say that it's probably loading it somewhere between 75-150 ohms depending on the relationship/interaction between the 5 ohm internal impedance of your cartridge and what it is seeing at the input of the Ortofon pre-pre.

If you had a cartridge with an 10 0hm internal impedance I'd guess it would be loading it right around 100 ohms assuming your're running into a 47K input on the MM stage.

But I'd definitely be curious to hear from someone with more technical knowledge than me and how one actually figures it out!

 

Well, you are off-loading the gain job to the SUT and using the MM pre for the RIAA curve, based on the assumption that the SUT can do a better job (with less noise). IDK about the loading calculation.

 

Some good information about loading with a SUT here.

 

I seem to recall you conducted your SPL tests between 10 & 11 o'clock. Did you do most of your normal listening at 1 o'clock?

 

Echoing this statement, I wouldn't try the Auditorium 23 Denon SUT with the 20x2L. The A23 is made for cartridges with a high output impedance like the Denon 103 (40 ohms). The 20x2L is much lower than that (5 ohms) and most likely won't be a good match to the voicing of the A23. YMMV.

 

IME good SUTs are generally more transparent the active-stages, but it is all about the quality of the transformers. I have a Hagerman with the legendary Stevens and Billington TX-103s that is used in the high-end and expensive Music First SUT. It is extremely transparent.

 

No, but I've had it cranked up to 1 o'clock, so I know what those levels sound like in my room.

 

Congrats on the Phono stage. I have bought most of my gear from Soundhounds - they make a great cappuccino to boot. They've been in business for 40 years and I always enjoy my time there.

I had to sell my Audio Note TT2/arm3/IQ3 with my move to Hong Kong. The different frequency was the issue as AN would have had to do surgery on the motor positioning or some such thing. So I am looking later in the year to add a preamp to my system and get back into vinyl (which is rather huge in Hong Kong) - even the major outlets like HMV have big vinyl sections. I may again get the Audio Note TT2 but I saw a piece where Peter Bruninger covered Warrne's room at a show and those Triangle Arts kind of have me drooling. I know I shouldn't go by appearance but from Peter Bruninger and some forum reports that room was one of if not the best - in no small part to the turntables (and I have the speakers so...).

The preamp side of things is this - I am looking at the AN M2, M3 and M6. I can probably swing the M6 Line but then go a bit budget on the phono stage - or get the M3 phono or the M2 Phono and put more to the cartridge. The M2 really shocked me at how excellent it sounded for the money. Weirdly I much preferred the M2 with Quest monoblocks over the Meishu (which also uses the M2 preamp) .

The M6 is about as good as sane money gets - the model up (M8) is something like $60,000. So umm no. I kind of want to get my digital system in place first. So vinyl may have to wait a couple of years.

M6 line with M1 RIAA looks like an intriguing option or pony up for M6 Phono? My thinking is that separating the boxes is better and that M6 line with a separate M1 or M2 RIAA may sound better than the one box solution. But I could be wrong in the myriad of AN products trying all the combos is practically impossible.

 

Agreed. But I want to hear it anyway. The SPU version is the one for low-impedance cartridges. It's the only way to even know what the sound of a A23 SUT is like if I want to order the SPU version, regardless of a bit of a mismatch. From what I hear from owners, the A23 SUTs are pretty forgiving of such mismatches. Worth listening to IMHO.

 

But how do you know? I mean, I'm just going by specs.

 

The MCA-10 was reportedly made for the MC-10 cartridge which had a 3 ohm internal resistance. 30 to 60 ohms loading maybe?

 

Interesting... from the specs I posted earlier it looks like the MM stage "sees" is 675 ohms?
Or is the cart seeing a loading at 11 ohms?
It's a head-amp basically, so the loading seems completely different than a true SUT...
I honestly don't know what it's loading the cart at. I thought 11 ohms initially, now I'm not sure.

Frequency response: (idling) source impedance > = 3 ohms: 3.5 Hz to 900 kHz - 3 dB
Frequency response: (completed with 300 pF) source impedance: > = 3 ohms: 3.5 to 400 kHz - 3 dB
Frequency response: (completed with 300 pF) source impedance: > = 3 ohms: 7 Hz to 200 kHz + 0/- 1 dB
Distortion over all (at 70 mV output voltage): < 0.1%
Input impedance: 11 ohms
Max. input voltage: 6 mV
Voltage amplification at 3 ohms source impedance: 33 dB
Output voltage with MC 10: 1 mV/cm/s
Output impedance: 675 ohms
Recommended completion: 47 kohms

My Cinemag SUT supposedly arrives here tomorrow, so this will be out of the mix.

 

I just used the old "10 x Internal Impedance for proper loading rule". Who knows though.

 

That's a pretty solid rule of thumb for loading a cart, I'm just curious what the MCA-10 actually loads carts at!

 

The input impedence spec of 11 ohms means that the cartridge will be loaded at 11 ohms. In those days that was about the recommended load on a 3 to 4 ohm cartridge. Nowadays 11 ohms is about right for a 1 ohm cartridge.

 

That was the room that I set-up, using TriangleART turntable/tonearm/cartridge, Music First Audio step-up & pre-amp, and Audio Note electronics and speakers.

 

As of January 1 2015, I am Music First Audio's exclusive importer and dealer in the USA for their SUTs and transformer-based preamps. (Texting now from CES)

 

Thanks for the clarification Warren.