I do not know why, but a solid state preamp and a tube amplifier sounds backwards to me. Most folks like to add a tube preamp to a solid state amplifier to give some tube flavor to the sound while retaining the wide bandwidth and solid bass performance of their solid state amp.
I'm a believer in matching amp and preamp whenever possible, so, I recommend a Meridian G56 or G57 amplifier. Both are available used on this site.
I would suggest a pair of Manley Snapper monoblocks. They are a true balanced design and produce a real 100 watts from 4 EL34s per amp. Super liquid mids and great extension on the highs and lows. They sell in the mid 2K range used and are a great value. Low maintenance and killer sound.
While what you noted, adding a tube preamp to a solid state power amp is more common, I've heard some exceptional systems set up the reverse way. Those tended to be more expensive than I can afford, but there has to be good options for me.
Thanks for the recommendation, Meadowman, I will add the Snappers to the list of options.
Nightfall, What price range were they in?
Combined pre and amplifier costs were in the $6-7k range of the two systems I heard. Also, several people reported wonderful results with good solid state preamps and Cary power amps.
I usually don't mix, but it sounds like something I might want to try. That's what this hobby is all about, right? It is probably easier to find a neutral sounding solid state preamp than tube type preamp.
Nightfall, what speakers are you using? That will help dictate good choices for a tube amp more than the preamp that you plan to mate it with.
I do agree, however, with your SS pre and tube amp combination desire. I can say from personal experience that it works great, and I think that a tube in the amp spot imparts more "tube magic" than in the preamp spot.
My speakers are the Silverline 17.5. This is a nearfield system in a small room.
Just FWIW... It is an easy task to add a true balanced connection to nearly any amplifier. Now before y'all go off on me, keep in mind that I am associated with balanced amps and preamps, and that I have good reason for saying what I did.
I am **not** talking about a simple XLR connector, that is only hooked up to the RCA input, nor am I talking about an input transformer. The mod is simple and inexpensive, so if you want, your range of tube power amps suddenly got a lot larger if you are willing to have the mod installed. It will not affect the sound of the amp otherwise.
Atmasphere/Ralph, that is a very interesting comment. I have not heard that before but would be anxious to hear more. Of course, I would love to own one of your amps, but even used, they are outside of my budget :-( You indicate that such a mod is relatively inexpensive - can you elaborate more on what "inexpensive" is? Or is this cost very dependent on the amp? Thanks and I will check back in with this thread for more info.
With just about any amplifier it would be under $250.00.
With tube amplifiers, normally the grid of the input tube is driven by the input signal. Since we want to do balanced (because it sounds better), we will have an inverted signal to work with as well. That is applied to the cathode of the same tube through a coupling capacitor (which might also be the cathode bypass cap of the amp; lacking that, then one is added as the coupling cap).
For transistor amps, the extra input is mixed with the feedback signal, which is usually applied to the differential input of the amplifier.
Both techniques work quite well, and essentially in the same way. It requires the connector, and the connections into the circuitry, perhaps a coupling cap or resistor. Otherwise you can see that this is an inexpensive mod; in either case **the amplifier is accepting the balanced input in the differential domain** even if the amp is otherwise single-ended.
And FWIW, I disagree with Rrog, its **much** easier to find a neutral-sounding tube preamp than solid state! However I find that listener bias does apply; I regard a preamp with a deep and wide soundstage to be more neutral than one that lacks such a thing, similarly I regard a preamp without brightness as more neutral than one that is bright.
I am a very great admirer of your wonderful products, and my first choice was to go with a used pair of M-60's, or even an S-30, my budget simply would not also support one of your preamps.
I then originally purcased the Meridian, since it was balanced, with that in mind, and buying a used Atmasphere power amp. However, I have since been told that your amplifiers only perform optimally when linked with one of the preamps of your own design, unfortunately.
My Subject title was somehow lost when I posted my last reply. Sorry.
However, I have since been told that your amplifiers only perform optimally when linked with one of the preamps of your own design, unfortunately.
Most of the reviews you might have seen on our amps have been done for the most part with single-ended preamps. The amps don't care if the preamp is single-ended or balanced, however its a fact that balanced cables, if driven properly, will sound better for their own reasons. So by default the amps will sound better when driven by a balanced source and our preamps *are* balanced, but the amps are designed to work with **any** preamp.
Nightfall- I can attest that my M-60s sounded great driven by a wide range of pre-amps. However, if you are using an RCA connection, you may to use a shorting pin in the XLR inputs on the amp.
However, I have since been told that your amplifiers only perform optimally when linked with one of the preamps of your own design, unfortunately.
I have no personal experience yet with Ralph's products, but fwiw I believe I can state with certainty that there is no technical reason why that should be so. Both your Meridian and Ralph's preamps are fully balanced, and have low output impedance. The amp will not know the difference, although of course synergy between the sonic characters of those and other components in the system will come into play.
Given that you want a tube amp, I would expect that apart from the intrinsic sonic character of the amp itself, by far the most important interaction that is involved will not be between amp and preamp, but between the amp's output impedance and the impedance vs. frequency characteristic of the speakers. I could not find an impedance curve for the 17.5's, but if you or someone else could locate and provide a link to one I think it would definitely help to focus the recommendations you will receive.
Ralph, thank you very kindly for your reply, more timely than my checking back in with this thread. This information may very well change my requisites for an amp, which I am in search of at this moment to drive a new pair of speakers I am getting tomorrow. I know I should get tubed, but I am leary of the upkeep (I have had several tubes amps in the past) and more so the neurotic feeling that I am always convinced the tubes need replacing.
Al, I believe the SR-17s are a pretty easy load. I recall several people running them with SET amps, if I am not mistaken. Perhaps somebody else with first hand knowledge can chime in?
I have had mostly great results with pairing a SS preamp and a tube amp. It just depends on the products that you pair and your ears. For example, I have used a CJ PFR amp with several different tube amps for years - it almost always sounded great. By way of comparison, the Krell KCT - not so great; at least with my tube amps.
Why use a SS preamp? Black, quiet background, usually plenty of inputs, often a remote. It's not the only or even the best way to go, but it has worked well for me. YMMV
Thanks to everyone for all of your thoughts thus far.
Al said "I could not find an impedance curve for the 17.5's, but if you or someone else could locate and provide a link to one I think it would definitely help to focus the recommendations you will receive."
I also could not find an impedance curve for the 17.5's but the specs are as follows:
Design (Bass Reflex): 2 way
Drivers: (carefully made for Silverline by Dynaudio*)
One Dynaudio Esotec D260 1.25" soft dome tweeter
One Dynaudio Esotec 17WLQ vented double magnet
long throw 7" mid/woofer
Frequency Response: 32 - 32,000 Hz
Sensitivity (2.8V/1m): 90 dB/1W/1m
Max. Transient Output: 127 dB
Nominal Impedance: 8 ohms
Crossover Frequency: 3,000 Hz
Recommended Power: 15 - 300 WRMS
Dimension (H x W x D): 14" x 8'5" x 15"
Shipping Weight: 90 lbs.(pair)
Speaker Connections: Bi-wire
I'm now leaning towards an Atma-Sphere S-30 as perhaps my best choice. However, this choice may be problematic.
What finally sold me was a lot of additional research and uncovering something I had never known, and which is very unique. According to what I've read, all of the Atma-Sphere power amps have equivalent sound quality (assuming they are the current version, or upgraded to it) the difference is simply in power. Having heard some of their top amps, granted it was a few years back, that has me convinced this is the right way to go.
As for why the S-30 specifically? , Well, the M60's would drive my very small listening to temperatures that would make it impossible to use them almost half the year. Trust me, I had a friend who owned those in Chicago, and his room was larger than mine and still became very hot during extended listening sessions and were unusable in the summer.
And now to the problematic aspect of this. I don't know how many S-30's have been sold, but my guess is that it is not a terribly large number. I base that on the fact that they show up for sale so seldom here on Audiogon. Of course, their owners may be so happy that no one ever sells one? Honestly,though, I don't recall ever seeing more than one or two of these appearing for sale here in an average year. You see far more M60's and MA-1's, etc. And to complicate matters further, I would only want one of the older style Mk II's that are long, front to back, as opposed to the newer wide style models (I just really don't care for the appearance of the newer models). I would then send the unit off to Atma-Sphere to be upgraded to 3.1, all of which my budget can accomodate.
And to top it all off, last week, just moments before I was considering purchasing it and just risking that it would work well with my preamp (which Ralph has answered), someone closed a deal to buy one in mint condition for a very good price here on Audiogon.
So, in the end, please keep any recommendations or advice coming. While I can get by for say, a few months, I cannot honestly wait six months, or even a year for another S-30 MKII in great condition to pop up for sale, and may be forced to go in a different direction simply due to that reason. Things are never simple in the audio world.
Nightfall, there is another alternative. Its possible to operate our amps with less than the full complement of power tubes. So if you have a set of M-60s, you could run them with 4 or 6 power tubes instead of 8.
The M-60 was also made in the long chassis. It was known as the M-60 MkII.3.
Ralph, I had seen a similar comment in an ad listing that your amps do not require all of the tubes to be installed to operate. Is there a minimum number of tubes, ie. half or something like that which is required? Is this true of all tube amps (for the power tubes at least)?
I would love to own one of your amps, sound fantastic but I always think to myself, how much does it cost to replace all those tubes? Which may say just as much about my ability to afford one of your beautiful sounding amps.
Ckoffend, you can usually run the amp with half the power tubes. Its a good idea to derate one of the power fuses but that is easy- just change the fuse. This is not something you can do with any tube amp BTW.
The tubes are inexpensive since they do not require matching.
Ralph, is the S-30 equal in sound quality to the M60's? I read something a while back that stated that, other than the wattage differences, all Atmasphere power amplifiers had the same sound quality.
Just wondering as I wait for either the M60's MkII.3, or an S-30 MK.II to show up for sale. I would then plan to send the unit(s) to you to upgrade to 3.1 status.
The more that I think about it, and given a great deal of input from audio aficianados here, and elsewhere, my speakers would almost certainly be driven better by 60wpc than 30. Which means the M60 MKII.3 are clearly my best option. And, having given this a tremendous amount of thought, that is what I want, heat be damned.
The issue now, is that I've seen these on Audiogon no more than a couple times in the past few years. They were only made from October 2003, until December 2005. And I really just don't like the look of the newer, wide chassis.
Sadly, this makes it almost certain that I will have to make a secondary choice of amplifiers to purchase. And I really, really, want an Atma-sphere. Based on that, I can hold out for, say, six months, but after that, well, I will have to make a hard choice and actually buy something.
Ralph, thanks for the explanation on the modification. Can you elaborate a little more based on the following:
First, is what you describe the same technique that is referred to as cathodyne? From what I have gathered from this technique the signal is applied to the grid, one side taken from plate and the other phase on its cathode. I have also heard that there could be issues where the impedances are not the same. For example, plate source Z is say 20K and cathode source is 1K. In this situation the problem is at high frequencies, capacity overtakes the plate side and it rolls off highs, while the cathode side still works. The signal is then an algebraic sum of the original signal.
I'm not an engineer so I'm trying to digest this because it appears to be a very simple and inexpensive mod, but then I have to wonder why more people don't do it this way versus using an input transformer. Any additional comments and insights you have would be appreciated.
Clio09, the circuit you described is for a phase splitter in an amplifier. What I was talking about is something different.
For example, usually you are driving such a circuit with a single-ended voltage amplifier. The mod I mentioned is to that voltage amplifier.
I think that the reason no-one is using this circuit is that they don't know that they can. I've done it a bunch of times and it always works...
After some further research, I seem to find myself back at square one. As noted in previous posts, I had more or less made up my mind to go with one of the rare pairs of the longer style Atma-Sphere M60's when they appeared used on Audiogon(or elsewhere). The big concern was how long that wait would be. I can be patient for a while, but not forever, as I have a preamp sitting in its box unable to be used.
Earlier this week, I had an unplanned business trip to Chicago materialize. Since I was to be there over two nights, I contacted an old friend I had not seen in some years who then owned a pair of M60's. It turned out that he still owned them, and had upgraded them to 3.1 status. This gave me a recent opportunity to listen to them, as a reference point. I must say that I loved the sonic qualities of the amps. To me, they did not truly sound like other tube amplifiers (and I have heard a lot)or like solid state, simply like pure music. I was also amazed by how well each instrument and vocal was reproduced, and by the depth, and quality of bass reproduction. My friend is associated with a large group of Chicago area audio enthusiasts, and one of them that he contacted even brought his pair of Silverline 17's (virtually the same as my 17.5's) so that I could hear the amplifiers with them (THANKS Fred!)
And now, on to the unfortunate part. My friends system is in a room approximately 11x15. After perhaps two hours of listening, it had become very warm. And this was on a day when his home thermostat was off due to the 59 degree outside temps. His thermostat was at 65 orior to our listening session. My listening room at home is a mere 10x10. I am certain the heat put out by the M60's would make them imposible to use except during the winter months. No air conditioner could cope with it, Im afraid. We did try Ralph's recommendation, and we removed four of the power tubes of the M60's to see what difference that made. While the heat output dropped noticeably, the Silverline 17's sounded much less optimal with the decrease to 30wpc. They really seemed to benefit from the full 60wpc. The Dynaudio drivers, I expect.
Give the above, and my room size, I think I am now forced to go back and look at other options due solely to my room size limitations.
Ralph, if you happen to be continuing to read this discussion, your M60's truly sounded superlative. The ONLY thing keeping me from picking up a used pair and likely being happy with them forever, is the small size of my listening room, and the heat issue.
Anyone Familiar with Consonance Cyber 800 SE amplifiers? I've just read some very impressive reviews, and some are available at my price point.
Nightfall, thanks for your comments. 10X10 is a small room; it sounds like you don't need a lot of power. What I would recommend, if you liked our amps, is maybe an S-30, and a set of ZEROs.http://www.zeroimpedance.com