you should go with an 845 or 211 based set for both vocal liquidity and orchestral slam
30 responses Add your response
The magic one gets from SET amps is achieved usually with high-efficiency speakers that can generate high SPLs at low power inputs. What's the sensitivity of your new speakers?
If you don't need ear-damaging peak levels, one can use a lower-sensitivity speaker, but that combo still needs more power than the flea-powered (ie 2A2, 845, 300B) SETs can produce. Until I fell in love with a pair of Eminent Technology 8s, I used 50-Watt 805-based SETs, Antique Sound Lab Exp. 805s, with 86dB-sensitivity Quad 989s in a fairly large (c. 3200CF) room. Peak SPLs tolerated by my ears is c. 95dBA, and that combo satisfied that. I ran them full range--no filtering and no subwoofers--and the combo sounded excellent. See Art Dudley's review of the ASL 805 in 'Stereophile' here http://www.stereophile.com/amplificationreviews/304antique/index.html . The 805s proved to be a few dB underpowered for the ET8s so I'm now using Quicksilver V4s.
My significantly improved pair of 805s is for sale.
Provided you have highly efficient speakers with a reasonably high minimum impedence (95 db.+ efficiency and minimum 6 Ohm impedence), a very well built single-ended amp that puts out 15+ watts/channel will generate high sound pressure levels. You will likely not have the bass tightness you want, however, as single-ended amps have little damping (unfortunately, you have to spend a ton of money to get a single-ended tube amp with the kind of output transformers and power supplies that will really control a speaker -- think Wavac or Lamm).
Will such a combination do justice to full-blown orchestral? It will be about as deficient as 99.9% of the standard (non-single ended) high-end stereos out there, meaning that it will sound pretty decent, but poop out when the going gets rough and also obscure the instruments and voices (very few stereos can realistically reproduce eighty people arrayed on a stage, playing instruments together).
Someone is selling a pair of Coincident Total Victory II's right now in the Audiogon classifieds. This is one of only a handful of non-horn type speakers that is full-range and built for low output single-ended tube amps, and will get you about as close to orchestral music with a single-ended amp as anything will (each speaker has eleven drivers -- they can go really loud, cleanly). The Coincidents are very well built, too. Here is the link to the ad:
Depends on design as regards the sound of a 300B amp. But as everyone knows, the speakers must be an easy load - higher and steady impendance (6+ min. without going much over 11-12 ohms), efficient (87db at least), and an easy phase angle through the crossover (which also contributes to impedance). Get these three things in a speaker (plus musicality) and the 300B should put an orchestra in your room. I use a room of almost the same size, 11 x 13.5 x 8, and currently use an Air Tight 300B to damn good effect.
I haven't bought my new speakers yet. I'm really starting from a clean slate. Only limitation is: Budget. Of course. Tomryan, you lost me at, "...easy phase angle through the crossover..." Can you break that down a bit for me. Also, which speakers are you using in your room. How's the bass?
Larry510; are 2a3's hard to find and/or expensive?
Raquel; see my limitation above. Thanx for the suggestion and advice however.
Jeffreybehr; I had read that review earlier and thought Atkinson's analysis was VERY harsh. Didn't you think? I think, towards the end, he said something to the effect of them being "broken" by most engineering standards? Did you get that same impression?
"...thought Atkinson's analysis was VERY harsh. Didn't you think? I think, towards the end, he said something to the effect of them being "broken" by most engineering standards? Did you get that same impression?"
Not at all. I was MUCH more swayed by Art's descriptions of the sound of the music, and, because Art used the same speakers I had and for other reasons, I bought a new pair. I believe that EVERY SET will measure similarly.
Remember, SETs are designed to make glorious-sounding music and NOT to measure well.
All things being equal (power, class A, good components) a similar powered push/pull tube amp will have a bit more "slam" than a comparable SET amplifier. A quality 300b push/pull interstage coupled hard wired amp with quality trannies will make your heart sing on complex orchestral works with the right speakers.
Phase angle is a by product of the crossover design. It's a good way to measure some of the difficulty or ease the amp will have driving the speakers. A benign phase angle will reflect a stable impedance load and therefore an amp has to work less hard to get the speakers up and running.
Having a stable (not to low and not too high and not wild swings) impendance load is just as important as efficiency. A speaker can show 91db eff. but have a wide impedance swing across the frequency spectrum (say, 3.5 ohms to 20 ohms) and therefore require a great deal of current to get going. Some Wilson Audio designs have fit this description.
Merlin TSMs are kind of the opposite - efficiency of 88-89db but a very stable and quite narrow impedance band and therefore quite easy to drive. I had a pair of them which the 300B amp drove just fine in my small room. Same thing for two ProAc models. I now have Harbeth C7s which, while wonderful speakers, need some current to sound their best. The Air Tight does not work well with them so I have a Plinius 50 watter which does superbly. Soliloquy speakers also are generally easy to drive but their sound is not to my taste.
Best thing to do is search this website for discussions about SET friendly speakers (there've been many of them). I would also always contact the manufacturer or importer of
whatever you are considering.
Also, 300B tubes are about 3 times as powerful as the 2A3 so you will need a speaker of at least 95db with and easy impedance load with the 2A3s. This substantially narrows your list. Horn speakers are an option but, man, do they have their own sound and you would absolutely have to try them in your room first. I've always found horns do best in med or larger rooms as I think you need to sit in the med or far field to not get that "honk-glare" effect.
I personally have never heard one that didn't have some of that stuff. I personally like a more relaxed, less tense presentation. But, this is all personal taste. I have a friend who loves his horn loaded Lowthers but I can't stay in the room for more than 2 minutes.
It's not that SETs, per se, can't handle large-scale orchestral music, it's more the case of people trying to couple inappropriate speakers to low-powered SETs. I have no problems with 8 watts of SET power (parallel 2a3s) on 99 db/w efficient speakers that are an easy load. I also get reasonable volume level with a pushpull 45 amp (about 3 watts). Both can do the closing minutes of Mahler's 8th at reasonably realistic levels.
By the way, I think choral music is a much harder test of output cabability for most amps than orchestral music. At surprisingly low subjective levels, choral music can start to sound strained and rough. Try Rachmaninov's Vespers, as an example of this phenomenon.
not agree with Jaybo, sorry. I have a set amp (master sound 845) driving my SAP J2001mkII horn/hybrid speakers. Most orchestra works sound wonderful with fast, accurate and natural music. Set amp can drive big orchestra easy, depends on matching equipments.
Patricia Barber and stuff like.... Patrica Barber, sounds fine with most of system, no need for high end system.
A quality SET does not sound mushy or bloated; it simply has a bit less "slam" than a comparable push/pull design. The SET has a bit better/lusher midrange than a push/pull.
If I wanted a quality tube amp making at least 20 watts with good dynamics the 300b push/pull interstage coupled dual monaural design would be at the top of the list. A 211 based SET designed to run up to 30 watts would also be on the list but it is more expensive to build than the push/pull due to transformer requirements.
Getting satisfaction from listening to large-scale music through SET amplification is not a function of the amplifier alone, but instead the combination of speakers + amp. On my 101 db/w/m Zu Definitions and Zu Druids, my various SET amps can produce explosive dynamics and project convincing energy along with tonality into the rooms the two systems operate.
As others have noted, an 845 or 211-based amp is a great way to get SET focus and intimacy with scale. 25w per channel goes a long way in a 101 db/w/m speaker. Most 300B amps sound progressively less incisive pushing complex, large-scale music at convincing domestic SPLs, the signature bass bloom and rich midrange thickening articulation. But as usual, this is a matter of cost. There are some highly evolved 300B amp designs at high prices that manage to tame the excesses of typical 300B sound to make it quite objective yet richly expressive at the same time. So getting what you want is also a function of finances.
If you are playing in the $6000+ region for SET amplification, you can get equally credible but different signatures from 300B, 845, 211 amps. But if you are considering an amplification allocation under $3500, don't let purist sentiments keep you from considering various single-ended KT88 options. They're not triode, to be sure, but some are quite competitive. In between, especially if you consider used amps, it can go either way. For instance, there is on Audiogon right now a used Audiopax Stereo 88 power amp (no, it's not mine). This is a single-ended KT88 that delivers 15/15watts of world-class clarity and on something like the Zu speakers is fully capable of impactful sound from an orchestral recording. The only triodes are in the input section. I think you can find that one for around $5K. You can also find Parallel SET offerings that retain single-ended attributes with more punch than a single tube outputting single-digit watts can muster.
But I'd have no trouble going back to my 7/7w 300B integrated even on symphonic music, if some combination of circumstances suggested I should.
I currently run my 99 db/w efficient speakers with a SET amp using parallel 2a3s. That is plenty enough power. While I like the sound of this amp very much, I also get pretty good results with pushpull triode amps as well. I know that there are a lot of people who will say that only a SET can deliver certain desirable qualities, but, since everything is a matter of finding acceptable compromises, if you don't have suitable speakers, if you prefer more control in the lower bass, etc., you should also look at good pushpull alternatives.
I have a 45-based pushpull amp that I keep as a backup (I may use it to bi-amp my system some day. It is not a shabby alternative to my SET amp.
Thanx for all the great feedback. I went ahead and bought a Cary CAD 300SEI (Sophia 300b). For awhile, I'll be listening to headphones only (Senn HD650s). Speaker selection now is wide open. Actually, it's probably not. I have a really dinky room, approx 13x11. I'm sure there are only a few speakers that are Full Range (or should I consider monitor and sub?), highly sensitive, and work well close to the walls. Oh yeah. And around $1,500. So, selecting the few that meet my criterial should be easy. Having your choice of 50 speakers that will work is probably a harder decision. (Read: sour grapes)
I use an 845 SET putting out 17 watts into Living Voice Avatars. I like all music, but if anything have gravitated to Opera and large orchestral music with this combo, they sound glorious. If you have tube friendly speakers 94db plus, with no dips into low impedence, IMO 7 watt 300B's will do fine for small scale Jazz, chamber music etc. A 17 to 20 watt SET will be perfect for the larger scale music, with appropriate speakers. Of course more and more manufacturers are bringing out "tube friendly" speakers. Look at the interesting industry SET review on www.6moons.com
I am not saying the SS super amps won't give you better base, perhaps dynamics, but they can't give what a SET will.