Raul,
If you don't want an argument then what exactly was the purpose of your last post?
You have mis-stated my position on SUT's (again), but if that makes you feel good then I'm happy you're happy. Feel free to do it three times a day, with meals, as needed.
Doing what I can to control health care costs,
Doug
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Dear Doug: ++++++ " At ultimate performance levels, however, it is now my belief that a properly implemented gain stage will outplay any trannie. " +++++
After all that time and after several post by your self about how good were the SUTs and after several discussion against/with me now your mind change in favor of active gain phono stages: good.
This is only for the records ( no argument about, please.): it is what you post about:
+++++ " For the record:
- some of us love them
- some of us tolerate them
- one of us hates them with a fiery passion. " +++++
" one of us hates.... ", that's me. It is nice to " see " that I'm not in the wrong road after all.
Like the people say here in Mexico: " the time put everything and every one on the right place ".
Doug, those fets on the MC stage...??????
Regards and enjoy the music.
Raul. |
Dear Eldartford: Great!!!!
Regards and enjoy the music.
Raul. |
Dear Swampwalker: +++++ " I was not thinking so much of an attempt to compensate, rather a better interaction btwn either an SUT or a gain stage with a certain kind of cartridge or line stage.... " +++++
Your way of thinking is right on target. No one in his healthy brain sanity can speaks about the use of SUT for compensate for some problems over the audio chain.
" interaction "/ synergy that's the name of the game in audio. The SUT certainly has no synergy with cartridges and that's why we have to go for active gain stages. The SUT is the " easy " way to hide bad phonopreamp designs. These bad designs add a bad medicine ( SUTs ) trying " to help " but the SUT not only does not help but increment/continue the signal degradation. The source of the problem is in the origin: bad design.
" Interaction with line stage ": in my opinion the active gain phono stage must be integrated with the line stage, in this way we can have a better synergy. Of course we could go for and stand alone/external active gain phono stage but here we can lost synergy, not only because we need additional cables and connectors that function like filters/veils to the signal reproduction but because the phono stage could comes from a manufacturer different from the line stage one.
Well as you can see this is a very complex problem. That's why I post about SUTs: " a cheap solution to a very complex problem ".
Regards and enjoy the music.
Raul. |
Rauliruegas...Agree that dirct coupled amps are best. I have some Kenwood LO-7M monoblocks that are direct coupled. Such an amplifier is really a DC power supply, with high slew rate and analog voltage control. |
Dear Eldatford: Yes, I agree with you and I respect to every single preferences that have the people.
I'm only given my opinion/answer to an especific Downunder question: " Besides providing gain, are good quality MC transformers transparent to the signal they are providing the gain to?. "
I think that the question here is not which proponents exist about the subject but which way is best for achieve a better quality music reproduction.
I know that are many SUT proponents but that does not means they are right about. The SUT is an easy way to hide bad designs, but the medicine ( SUT ) is worst than the illness ( bad design ) because to a bad design you have to add another disadvantage named: SUT. My advise is that the SUT proponentes have to learn about. Like Tom say: " Knowledge is power. "
Btw, ++++ " some prefer transformer-coupled amplifier stages over capacitors " +++++, as you know this statement ( both designs ) is the non right way, the right way is: direct coupled amplifier that is always a challenge for the designers.
Regards and enjoy the music.
Raul. |
Rauliruegas...Transformers do have their proponents. In addition to the MC phono aplication, some prefer transformer-coupled amplifier stages over capacitors, and some prefer variable coupling transformers over pots for volume control. |
Dear Swampwalker: +++++ " One additional thought or question I would throw in the mix is this- are there certain upstream or downstream choices that affect the step up vs gain stage decision, all other factors being equal? " +++++
In my opinion, other than money/price, no know-how and poor interest in music quality reproduction I don't think exist any upstream/downstream about. The choice must be active gain stage.
Regards and enjoy the music.
Raul. |
Dear David12: +++++ " . There are still compromises with the "ultimate", design, such as the boulder. Perhaps its more interesting to discuss which way you would design the best stage you could build, at any cost, would that be active or transformer based? I don;t know the answer. " +++++
I don't want to speak about Boulder, but you can read the review on Stereophile and if you read it in deep, both parts: subjective and objective/measurements ones, you can see that maybe it is not the " ultimate ". Certainlly by price it is, the phono/line preamp it is only: 46K.
Now, if you take a look around phonopreamps: what do you find?
FM Acoustics, Boulder, Rowland, Pass, Klyne, Levinson, Krell, Aesthethix, Supratek, Gryphon, etc, etc.: all these people choose active gain stages not SUTs Do you think that these " facts " are a good answer to your question?
Do you think that we take 12 years of work with our self active gain design just for fun?
Regards and enjoy the music.
Raul. |
Dear Downunder: +++++ " Besides providing gain, are good quality MC transformers transparent to the signal they are providing the gain to. " +++++
In absolute terms the answer is: NO!!!, it does not matters design or price.
Thom posted that this subject is very contentious one and I think that it is because the people no know-how and because they never had the opportunity to heard the right active gain phonopreamp.
Next are some issues about step-up transformers SUTs:
The SUT is an old patch for bad SS phonopreamps designs and for the inherent limitations on tube phonopreamps for handle low output MC cartridges. It is a " cheap/easy solution to a complex problem ".
Any SUT has many inherent disadvantages like: distortions generated at the core ( it does not matters if is: air core ), heavy phase discharge ( landslide ), high apt to take hum, the wide zone ( band ) can't go down to DC, severe roll-off at high and low frecuencies, the reactive impedance on the SUT is incompatible with the cartridge impedance: this cause that we never could have flat frecuency response when we are using SUT, this mismatch between the impedances promote that the signal that pass through any SUT will be equalized.
Any time with any of you we can make the tests and prove all those disadvantages and others like the additional cables that you have to use, additional connectors, the SUT is an additional ( filters ) link in the analog audio chain.
I want to let clear that there is no single advantage, in any way, using SUT's, any of them.
The SUT always be a : wrong PATCH.
In the past and for many years I was thinking that the SUTs were the best way to go till I learned about. I try almost any SUT out there, in my system or in one that I knew very well, and always corrupted the signal that pass through it, that's why in the last 10-12 years we design and active gain and perfect a phonopreamp with out SUTs: we try every single technology: bipolars, fets, mosfets, tubes, combinations, etc, etc ( btw, Doug: bipolars for MC and fets for MM cartridges ) and this self design is what I'm using for and its quality performance is far away ( very far ) from SUTs design and far from any SS or Tube today comercial design. In our design there are no trade-offs.
There are not many good phonopreamp out there ( and are expensives ) and this is because it is a great challenge to design a good phonopreamp that can achieve targets like: accuracy on RIAA eq. ( inverse ), deviation no more than 0.05db between 20 to 20Khz, enough gain with out noise and distortion free.
The challenge is too big for some phonopreamp designers and they choose the " easy path ": SUTs and you people have to suffer. That's not fair, for you and for the music reproduction.
Regard and enjoy the music.
Raul. |
David12. I have looked at the K&K p[hono stage. Does it have nice tube warmth?
In M Fremer's colum last mnth he reviewed the art audio ref1, which is based on the K&K. he commented on overloading and distortion when using a .5mv lyra titan. This does not sound right. have you have any of these issues?
cheers Shane |
I was not thinking so much of an attempt to compensate, rather a better interaction btwn either an SUT or a gain stage with a certain kind of cartridge or line stage, or amplifier. Just a question, I have no idea if that is true or if any generalizations can be made. |
Hi Doug,
Hop onto Dave Slagle's forum at Intact and join the frey.
Likely you can get into the evaluation loop as these are being developed.
The forum category is near the top - "MC Step-ups". Note that in order to view any attached photos or graphs, you need to establish a logon. The text of the posts is there for all to see however.
This thread ought to whet your appetite:
http://www.intactaudio.com/forum/viewtopic.php?t=139
Once again ... the dislaimer: NO COMMERCIAL INTEREST, YMMV, etc. etc.
Cheers,
Thom @ Galibier |
>> I am looking forward to continued discussion on this, but mostly, I would love to hear a demonstration.
Open invitation to one and all! Hear it live! Bent Audio Mu's vs. one "no holds barred" FET gain stage.
Of course I defer to Thom's experience with better SUT's. If he'll ship me one we'll include them in the shootout and report. ;-)
I've also heard Frank Schroeder's unobtanium SUT's. They were certainly very good, but some other parts of the system were insufficiently transparent for me to note specific differences between them and the Bents.
>> ... are there certain upstream or downstream choices that affect the step up vs gain stage decision, all other factors being equal?
Great question. One thing that comes to mind is frequently balance. If a system or room happens to be tilted up or down at either end, it might be possible to compensate with SUT's by adjusting reflected impedance. I would never recommend such a "band-aid" approach, but it might work for someone who doesn't have the time, interest or resources to solve the problem directly.
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This is a very interesting thread. David12, you are right on the money. While for certain goals or design criteria, a certain design approach (step up vs gain) may be superior, its highly unlikely that any individual design does not involve compromise. Picking one design approach vs another is the easy part, based on your design criteria; effective implementation is the hard part if cost is a factor. I am looking forward to continued discussion on this, but mostly, I would love to hear a demonstration. One additional thought or question I would throw in the mix is this- are there certain upstream or downstream choices that affect the step up vs gain stage decision, all other factors being equal? I have no idea and look forward to comments from others. |
I can't compete on the technical descriptions, which are helpful by the way. In fact I have just changed from a good SS conventional phono stage, the Clearaudio reference, to a K&K phonostage. The lateral is a JFet/tube hybrid with Lundahl transformers. In the past I have tried Tom Evans and Trichord stages too. The K&K is head and shoulders above the rest, more detail, much more dynamic, much quieter, no better imaging, but every other parameter is better. Is that because transformers are intinsically better than active gain stages? I am sure it is because in this case, the K&K is a better thought out design.
At the risk of being obvious, are'nt you dealing with a set of compromises particular in good as opposed to the best gear. For most of us buying the good, it may not matter if the phonostage is active or with transformers, or the amp is SS or tubed, what matters is the skill of the design, which in turn depends on the balance of compromises made. There are still compromises with the "ultimate", design, such as the boulder. Perhaps its more interesting to discuss which way you would design the best stage you could build, at any cost, would that be active or transformer based? I don;t know the answer. |
Audio Note KSL-spx, - their step up Transformer - did anyone try it? |
Hi Doug,
I would categorize the S&B in the very, very good category, but not in the world-class range of component. It continues to be my humble opinion that an extreme solution, whether it be a step-up or an active stage will be satisfying to the music lover.
Coming out of an after hours session at the Rocky Mountain Audiofest this October, the seeds of some very cool development in MC step-ups were planted. I have NO COMMERCIAL INTEREST in this project, but check out Dave Slagle's Intact Audio site (the forum) for ongoing discussions about what Dave is developing (http://www.intactaudio.com/).
In that Saturday night session, the likes of Frank Schröder, John Atwood (Artemis Labs), Dave, and others got together to play with step-ups.
Dave's first attempt nudged into second place behind Frank's unobtanium step-ups. For this experiment, Dave reached into his parts bag and pressed into service an autoformer volume control. In other words, it was an adhoc attempt, done on the fly, and not in the least sense of the word, a mature design.
In recent months, the boys in Fort Collins have been playing with dedicated MC step-up designs from Dave. These are the "boys from Colorado" referenced in various threads on Dave's forum. They have been playing with dedicated designs - trannies that surpass Frank's on a range of cartridges from Myabis to a Lyra Olympos.
There are some characteristics of step-ups which might be beneficial to musical reproduction.
One of them which comes to mind is bandwidth limitation. Note that trannies like the Jensens go out to 100KHz, so I'm not talking about premature HF roll-off. I suspect that some of that "juicy" sound inherent in good iron has to do with the filtration of RF Interference. This is speculation on my part.
Secondly, consider the moving coil cartridge. It's a motor assembly. The better cartridges have a reduced winding count (and the resultant output voltage) in order to minimize moving mass. Given a compatible transformer, what better way to effect gain than to "restore" some of the windings, but outside the cartridge so moving tip mass remains optimized ?
Thirdly, bass response is a function of the inductance of the trannie. It's definitely another one of those matching issues we've discussed.
Once again, it's my contention that there are multiple ways of solving a problem effectively, and the above thoughts are most definitely slanted toward my bias - in favor of trannies. I have no doubts that an extreme approach to active gain can also accomplish these ends.
Certainly, we're in agreement, that at real-world prices, MC step-ups rule.
Cheers,
Thom @ Galibier |
Thom,
Brilliant post. Thank you very much for saving me alot of typing!
The Bent stepups are indeed excellent, though as Thom implied there is no one "best" trannie. Adjusting the reflected impedance on the secondary side (very easy with the Bent's) is vitally important, but even then you have the issue of the primary side impedance interacting with the cartridge. I suppose this is why (IME) some trannies work better than others with a particular cartridge even after reflected impedance is optimized.
As Thom also implied, using trannies well involves a lot of work. LOMC's are extremely sensitive to reflected secondary side impedance. Those who claim trannies have non-flat frequency response simply haven't done the necessary work.
We spent dozens of hours swapping cheap resistors. Finding the optimum value for a cartridge almost always requires doubling up resistors on each trannie. (This allows much finer gradation of resistance values.) Having done all that, we then spent hundreds of dollars on multiple sets of high quality resistors. I'll discuss those results in another post if anyone cares. The results with every cartridge were always an even frequency balance.
At ultimate performance levels, however, it is now my belief that a properly implemented gain stage will outplay any trannie. A transformer must, by its nature, diminish amplitudes and smooth waveforms. The effect in a good trannie may be very slight, but it cannot be eliminated. This means a diminishment of dynamics and a rounding of notes (bloat, in plain language). My new preamp/phono stage is built as Hi5harry described, FET followed by RIAA circuit followed by tubes. It easily outplays the Bent's and every other tranny I've heard. I have a friend who owns nearly 20 different stepups. He's used some of them for over 30 years. Once he got his new preamp (same as mine) they all went into the closet.
Beating the Bent's and Cotters takes a large outlay however. If you aren't able to spend $6K+ on a privately built preamp or $10K+ on a commercial one, the trannie route will often do a better job, provided you're willing to do the work.
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the transformers sounded a little more dynamics in the bass I think you'll find this is due to better loading -- rather than a characteristic of trannies at large. What a well implemented tranny should offer is a little bit of extra signal purity... Makris explains all of this above. You can also consult Stevens & Billington's (S&B)site (link above, FLemke) for some implementation info. Finally, experience I've with S&B trannies is very encouraging. I believe Bent uses these for their products. |
When I had MC pickups I initially used a Signet transformer that was almost the size of a beer can, which I gather is larger than most. I was very skeptical about the merits of a transformer, and it was only after I abandoned it and went on to active MC preamps that I realized how good the transformer was.
This is probably an area where generalities are inapropriate. Results will be highly dependent on which transformer and which pickup is involved, and which preamp you compare it with. |
Thom. thaqnks for that, The Bent audio Mu transformers appeals to me as it is easy to change the loading and seems to have a good reputation.
What is the difference between changing the load on a MC transformer compared to changing the loads on an active gain stage. Most active gain stages have several impedance loading options these days.
there still seems to be no consensus on whether a MC transformer adds bass or takes it away.
My only expereince with MC transformers was with the Manley Steelhead and the transformers sounded a little more dynamics in the bass compared to the straight gain - sound wise not my cup of tea, a little hi fi sounding
Rwwear, I think you will find that ARC have dereleased their ref phono stage and replaced it with the PH7 phono. get / tube like the PH5 but souped up to the max. |
Rwwear,
Look at these. When I get a few buck,I am going to mod my 834p with a set of these mosters.
http://www.stevens-billington.co.uk/page103.htm
Makes the jensens look like toys.
Tim |
I've used a couple of inexpensive Denon step-up trannies with Denon DL-103 carts and think they're great. Excellent synergy. Dave |
The Jensens are amongst the best. Audio Research uses them in their reference phono and Rowland uses them as balancing transformers. I think though Audio Research is charging a lot of money for something you can buy directly from Jensen for a couple of hundred bucks. |
This topic can be one of the most contentious ones you'll find in this forum. There are people I respect greatly, but with whom I disagree on this topic.
The relevant question (as far as colorations are concerned) is to compare an MC step-up against an active gain stage.
I fear that those who report bad results with step-ups are wrongly accusing the architecture when it is the implementation that is at fault. Anytime you're given freedom to choose (a transformer, interconnect, line stage, etc.), you have an opportunity to screw up.
Matching a trannie to a cartridge (assuming we're talking about a quality trannie) involves knowing the DC Resistance (DCR) of the coils in your cartridge. You're typically looking to match the cartridge's DCR with that of the transformer's primary ... with the trannie being as much as double the cartridge's DCR, but not much more than that.
Secondly, there is the issue of the reflected impedance that the cartridge sees. In it's native mode (without additional loading resistors), a cartridge will "see" a 470 ohm load through a 1:10 step-up, when connected to a phono stage with a 47K input impedance.
You can run into problems if for example you have a cartridge that wants to be loaded at 1K or 5K and you're using a 1:10 step-up. You will have excessive high frequency roll-off. This is not normally an issue, because the numbers tend to work in your favor. For example, almost all .2mv to .5mv cartridges can use a 1:10 step-up from a gain perspective, as well as from the perspective of the impedance they like to see, which is typically well under 470 ohms. You can always add resistors in parallel to drop the load, but you can't easily raise it.
For some excellent discussions on transformers, go to the Jensen transformer website (http://www.jensen-transformers.com/mc.html). On my support page, I
have some links to excellent articles on step-ups - written by Jim Hagerman (Hagerman Technology) and John Chapman (Bent Audio).
Trannies are yet one more instance of the old adage - it's not so much the chosen architecture, but how well you implement it. I happen to like them because it allows you to tailor a phono stage to a particular cartridge. Other people are baffled by such choices. Others have fallen in love with the colorations of their favorite MC active gain stage.
Knowledge is power.
Cheers,
Thom @ Galibier |
You're going to get a some interesting responses to this question. The two sides will probably confuse you more than help you. All I know is that I have a Hagerman Trumpet MM phono stage and the designer himself confirmed for me that the MM version of the Trumpet combined with a quality MC step-up was a better configuration than buying the MC version of the Trumpet. In any event I think system synergy is more critical when using a MC step-up as you're adding another piece to the chain, but I have experienced great sound with my modest K&K Lundahl and haven't had any issues with bass. |
I agree. I have had no luck with them. I think the j-fet before the tube gain stage ( as in the new Audio Research phono pre amps) is going to be the way to go. |
All of the ones I've heard cause harm to the bass and reduce transparency. |
