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Denon SUT or Micro Seiki head-amp?

Hello there. I recently bought the famous Denon DL-304. I connected it to my Project Tube Box II, and immediately noticed that something was quite lacking. I did some research and only then learned about this cartridge being extremely low-output, and the need to somehow boost up its sound. Right now, the options I have here in Argentina are reduced to:
1) Denon AU-320 step up transformer.
2) Micro Seiki MTA-41 head-amplifier.
The Denon could seem like an obvious option, since it matches the cartridge impedance exactly (40 ohms). But then some say it could veil the extraordinary level of detail of the DL-304, and I wouldn't want that at all. The Micro Seiki, on the other side, is a mystery: there's practically no info about it on the internet. I only got to know that technically it would fit the DL-304: it is good for cartridges between 1 and 50 ohms of impedance and from 0.1mV (DL304's being 0.18). The specs here: http://www.micro-seiki.nl/Accessory.html
Can anyone help me decide here? Thanks for any advice!
fedocable

Showing 6 responses by swampwalker

swampwalker's avatar
swampwalker
5,138 posts
 
The Micro-seiki "head amp" IS an active gain stage, which if it does not result in noise, can often provide better results than an SUT which can result in ringing and will "magnify" any cable or loading mismatches.
swampwalker's avatar
swampwalker
5,138 posts
 
Fedocable- Marakanetz MAY be correct but if there are import limitations it might not be possible to find a sufficiently high gain full function pre-amp or phono stage. Using the KAB gain calculator, a cart w 0.2 mV output requires about 64 dB of gain. The Pro-ject Tube Box II provides 60 dB of gain. Pretty much any active pre-amp will provide the additional 5-10 dB gain from the line stage, so inadequate gain may not be the problem. I'm assuming you have switched the selector on the back of the Tube Box to MC and are running the output of the Tube Box into a line level input of a pre-amp.
swampwalker's avatar
swampwalker
5,138 posts
 
Fedocable- Your welcome. I suggested the head-amp because in a highly resolving system, I have preferred a high gain active phono stage vs. a xformer. I have very little technical expertise in this area, but I am told that one of the reasons is that xformers can "ring". Also, load matching is critical; I have heard differences in sound between only a couple of ohms in a xformer that has the the ability to swap in different values. I don't think (but really don't know) if that is an issue w the head-amp. Finally, the "step up" effect of the xformer also "steps up" any artifacts from the cable that is upstream of it. The 30 dB gain of the Micro seki is more than adequate and should allow you to run it into the MM side of the project (30 + 40 = 70 dB), which would tend to lower tube noise (if any). It's battery operated so no AC noise issues and has outstanding S/N spec (-120 dB). All that being said, a properly matched xformer can give very good results.
swampwalker's avatar
swampwalker
5,138 posts
 
Well, you know that 60 dB of gain is not enough, so you'd have to use the MC input which would give you 80 dB, which might very well be too much, depending on how much gain your line stage and amp supplies, room size, etc. If that were the case, you'd end up operating at the extreme low end of the line stage's attenuator, which generally is not a good thing in terms of channel matching. It also would create a big problem if your line stage uses a stepped attenuator and or has a logarithmic attenuation curve.
swampwalker's avatar
swampwalker
5,138 posts
 
Looking at some comments on-line about the amp you are using, there are some suggestions that the gain steps are a bit large at the lower end of the scale, so I think that 80 DB of phono gain would be too much; leaving you wanting more fine control of volume. So that would argue for the Micro Seki into the MM input.
swampwalker's avatar
swampwalker
5,138 posts
 
the Puccini Settanta is already a nightmare when it comes to "volume control": you need to have surgery precision with that knob.
That's what I was learning from the web reviews I read. Excess overall gain coupled with a finicky attenuator is a recipe for total frustration.
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