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Pre-Preamp' MC Amplification

It's yours if you want it. I nearly binned it, but like so much clutter, it now resides in the loft.

Jez provided a likely explanation of what happened, but it took out a tweeter on a 15 inch Tannoy when it did go phhhutt. Not a proper description, but his best, educated, guess was that it basically caused the Croft to produce quite a slug of DC. The tweeter coil looked OK until I used a lens, when the few fried turns were obvious.

Bummer! How long after you got it? I feel guilty now...I PM you.
 
I feel guilty now.

LLOL, no need, its just how the cookie crumbles.
It died around Christmas last year - not sure when it arrived, but quite some while before that.

Fortunately Frank (Cooky) spotted a tweeter on EPay and replacement was beyond simple to do - getting the driver in and out of the cab' took longer.
 
....
All have their strengths, but if I was to characterise, I'd say the head amps put you a few rows closer, and a little more dynamic presentation. A SUT by contrast is to my ears more relaxed, gives a better flow to the music, and as Vinny says, better sound staging.
That was my finding as well with SUT's even in comparison with a high quality MC only phono stage.
In my Burmester 808 preamp I have one MC and one MM phono module both are high quality and very low noise. I wanted though to run 2 MC cartridges in two different arms so I added a Music First TX103 SUT as a setup for the MM stage. At this point I had a Cadenza Blue in an SME V into the the MC stage and a Denon 103 in my L-07D turntables arm into the SUT and MM stage. As the latter combination sounded very good I thought would I try the Cadenza SME by this route to see what that sounded like not expecting much if any improvement. The result while not massively different was I thought worthwhile in just those areas described above and as that combination had the higher quality cartridge I stuck with that route at first.

My real reason for having two MC's was I wanted to add a good quality Mono cartridge into the L-07D arm and I bought a Cadenza Mono so as it would be a fairly close match to ally for the other Cadenza. The problem came with installation though as no matter how I tried with all sorts of arm and earthing combinations I could not eliminated a least some degree of Hum with the Mono into the MC phono module. Now I would have expected the route via the SUT to have been worst, but it turned out that it wasn't after a bit of playing around. No Hum and no noise unless you turn up the volume and put your ear close to the tweeter.

So the Cadenza Mono now goes via the SUT into the MM and the replacement (for the Blue) Cadenza Bronze goes into the MC module. The Music First SUT does have variable cartridge loading and both my preamp modules also allow variable loading with any value you want via parallel phono plugs. Ultimately I found a combination of the two added a little further refinement to the final sound.
 
SUT's generally are the least accurate and most coloured. They "round the edges off" a bit... Some like this.
Or a different interpretation would be that an SUT in combination with correct loading does a better job, at least to some extent, in flattening the rising high frequency response present in nearly all moving coil cartridges giving improved tonality and overall balance in an otherwise neutral system.
Some like this ;)
 
Comments so far do make me wonder about places where I'll not willingly tread - MC stages (well) up into the 4-figure price bracket......

A new P75 isn't far off that (£800 - OUCH!!), which I have used (Mk 2????), and it was OK but least preferred (by me) when compared to SUTs and head amp's - here, it sounded like a Michell Iso, which usually sell for around £250 (used)

As per Jez - if the ideal is minimal circuit pathlength, why would better mean higher cost? (No answer required - that is me just musing - I am sure that we all know...)
 
It is unfortunately not really a discussion it's possible to have in any meaningful way because to the non technical everything is "a black box"/"here be dragons" and so people will simply report which option they've personally preferred out of the few they've tried. This is kinda what I was getting at in my first post in this thread when I said we could make an automotive analogy to 4, 6 and V8 engines... ie if someones experience and purview of 4 cyl engines is a Austin A series with push rods and carb and 45BHP then they will have a hugely different view of 4 cyl engines to someone who's experience has been of a turbo charged VTEC, EFI, DOHC beast that revs to 8500rpm and produces 350BHP... But both could come under the 4cyl category...

It's easy to make a good sounding MM valve phono stage. MC stages of any type are much more difficult to get right.
Hence for many people yes a good SUT (and they vary massively!! Few are genuinely top notch) with a decent valve MM stage will I'm sure be the best they've heard.

A good head amp can beat the best SUT's (we're talking SUT's > £1K here). They are rare as hens teeth though and there is loads of "background noise" from the "valves/vinyl and horns" types that SUT's are the ultimate, which has been believed by many, especially the "all SS is sand/crap" types, which has reduced the demand for head amps, hence you will need to search hard to find really good head amps even to try one out.

When we get to MC phono stages there are so many possible permutations of circuitry within that "black box" that it's quite impossible to speak about "MC phono stages" generically. I'm absolutely NOT saying that generally MC stages will beat a good SUT into a good valve MM stage! I am saying that the very best MC stages will though...

Another thing is that you will often find people have bought a S/H decent valve MM stage for say £600 that would have been £1500 new and used it for a good while with an MM cart and long after the cost has been forgotten about they get a S/H SUT for £500 that again would have been say £1000 new... They then compare it with a £700 brand new MC stage and quelle surprise they prefer the SUT/valve set up! I've seen just this many times when this subject comes up.
 
I've never seen a solid state MC pre pre for sale - I'd say its a DIY job only. And all the ones I've seen are using obsolete parts like the 2sk170 which are getting hard to get. I'm sure there are alternatives to that, like paralleled 2sk880 or something.

Aftermarket SUTs are far more common though. I had some lundahls that I traded once, and they were very good. I think they were 9906 or something. Can't remember now. There's a guy who sells the transformers on lencoheaven and diyaudio, for dac output stages, he might be worth a look at some stage for this.
 
A MC pre pre is an MC phono stage - it goes between the cart' and the pre - hence pre pre(amp')
I'd not checked what the numbers were.

That said, we know that there are a (very) small number of head amp's available commercially.
 
A MC pre pre is an MC phono stage - it goes between the cart' and the pre - hence pre pre(amp')
I'd not checked what the numbers were.

That said, we know that there are a (very) small number of head amp's available commercially.

An "MC pre pre" is a head amp... if a rather awkward term for one.
 
Not really - it then has to go into a MM stage, not into a preamp'. It is just part of a pre-pre chain.

Semantics anyway - no doubt the meaning was a head amp' , not a MC stage :)

No. You are wrong. Head amp is more common (and does not mean headphone amp!!) but MC pre pre has long been an extant term for them.
 
Jez, this whole thing obviously confuses the **** out of some people.
If you look back towards the beginning of this thread, I tried to expain what was going on. Irrespective of obscure common names, my intent was to discuss what goes between an MC cart' and the pre', and a head amp' does not stand alone in that position, it is part of at least a two-part chain between MC cart' and preamp'.
 
Jez, this whole thing obviously confuses the **** out of some people.
If you look back towards the beginning of this thread, I tried to expain what was going on. Irrespective of obscure common names, my intent was to discuss what goes between an MC cart' and the pre', and a head amp' does not stand alone in that position, it is part of at least a two-part chain between MC cart' and preamp'.

No it's not! It can be just one part ie an MC phono stage... not all of them contain an internal head amp. Also a pre amp is completely superfluous in these days of 1-3V line level. A passive is all anyone needs. Of course a pre amp can also contain an MC phono stage... one box.
One upon a time a long way away cartridges were known as pick-up cartridges and before that as pick-up heads...
 
I have a lot of different MCs, some as low as 0.15 mV. In my phono stages - PSAudio Nuwave, LCR units from the middle kingdom and MF three input stage (M6) there is enough gain for all of them.

But I do have about 12dB in the preamp.

My experience with SUTs is very limited. I used an AT unit ($200) from the 70/80s and was OK, but kind of bland. I do see some really expensive units on eBay, so assume they have value to some.

If memory serves, head amps (and this is a correct name) were more popular in the past. Advent of something made having a lot of gain with ultra low noise in a single box much more available. Jez can probably tell us what that something was.
 
My first adventure into the world of low output MC involved a head amp, into an A&R A60 IRC.

The early 80s and a Lentek head amp. Wee little circuit running from a 9v PP3 battery encased in a heavy metal sleeve. Not the quietest thing but it sounded OK:

Lentek by Rob Holt, on Flickr
 


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