Can someone explain is there is a difference between the watts of a tube amp vs vSS amp, Looking to get a tube amp ,but i see that the watts are much less than the SS amps, So how do these Tubes amps with 25 -70 - wpc drive these high end speakers, I have a vintage pair of AR 9s and 2 mcintosh MC2200 amps in mono (400 WPC) to drive these ,what tube amp will power these under 3-4k new or used, Thanks
If you are starting with the premise that you need 400 wpc, and you have a somewhat tight budget restriction, most tube amps are not good candidates. I think that even ultra expensive high powered tube amps don't sound very good and would stick with solid state for delivering that kind of power.
But, are you certain you really need that kind of power? There are meters that can tell you how many watts are being delivered to your speakers. If you use one of these meters while playing at typical volume levels and at the highest volume levels you play your system at, you will have a better idea of your power requirements. If it turns out you do need more than 50 watts, it might best to just stick with solid state.
First off yes, there is a difference between tube watts and ss watts. Tube watts seem subjectively to be about two to three times as powerful, authoritative, whatever you want to call it, as ss watts.
When it comes to driving "these high end speakers" its not the size or cost but the impedance of the speakers being matched to the amp that matters. Any fairly efficient easy to drive speaker, you won't need a lot of tube watts to be satisfied, volume-wise.
Which is why yogiboy is right. Although I would prefer, you are better off using different speakers with a tube amp.
There are lots of great tube integrateds that, matched up with some nice efficient easy to drive speakers, will easily outperform your current combo.
Or if you are married to the vintage look then let the tubes go. A man's got to know his limitations.
I too have heard the claim that tube watts are subjectively more powerful than solid state watts, and I have sort of felt that way myself. I actually think that good tube amps, coupled with appropriate speakers, sound much more lively and engaging than solid state amps playing at the same volume; you have to crank a solid state rig up to a higher volume to get the same sense of liveliness, hence, the impression that tube amps sound more powerful than their rating.
The actual numbers would suggest otherwise. The published tube amp output is typically where the tube is actually distorting quite a bit, and a more comparable wattage rating to where solid state is rated would actually be MUCH lower. Arguably, a tube watt is less than a solid state watt, but the subjective impression is quite the opposite.
The AR 9 is somewhat of a beast to drive (87 db/w @ 4 ohm nominal impedance). While it is possible to use a small tube amp successfully, it would mean accepting modest sound levels, a smaller room, etc. I think solid state is more likely to be the best choice, but, you never know unless you audition some tube gear in your system.
I find it interesting that so many audiophiles, particularly those who favor high-powered amps, measure quality by how loud an amp will play. For me, the measure is just the opposite--how soft can an amp play and still deliver satisfying sound.
Tube W sound more powerful than SS W because tubes distort more and higher distortion will be perceived as higher loudness even if the measured SPL is the same.
Oh my merciful heavens. Please read Roger Sanders excellent white paper on tubes vs solid state. He explains in language anyone can understand why tubes sound different than solid state. Much of what I have read on various fora in response to questions like you have posed is amassed in his white paper. Google his website Sanders sound systems.
With tube amps it is not all about the advertised wpc, the transformers ,power supplies are the key and the quality . i have seen a 18 watt parallel SET amp with great monolith transformers destroy a very respectable 100 watt SS amp by having big high headroom transformers that makes all the difference in the world.
Its a long road my man. With a thousand explanation your best bet is to try it both and be the judge of it. Realistically and no offense to anyone, even audiophile guys for years and years still bonds with buying new gadgets almost every 1/4 of a year. How do you explain that? My advise to you is make the most of what you feel is good to you. If you find your component singing to you, she is the one.
Sanders biases his arguments towards his own amps which are admittedly great values in high powered amps. Yes, high powered tube amps waste a lot more energy as heat than an AB SS amp. He is also expressing his opinion with a bias toward driving his electrostatic speakers. He dismisses OTL amps off hand. He is right that you need to use a lot of tubes to reduce the impedance of the output section but once you do so they are every bit as effective at driving electrostats as SS amps. Sanders is right about clipping affecting the sound quality of amps. Power is expensive it is also everything in terms of producing realistic dynamics at comfortably loud volume levels. Boulder has come to the same decision. There is no such thing as too much power and I am inclined to agree. I am also guilty of being attracted to notoriously inefficient loudspeakers. All things being equal you are way better off buying more power than more cables.. Audioman58, transformers do not make power no matter how big they are and no transformer is always better than any transformer. There is no SET amp capable of the kind of visceral dynamic sound close to being realistic. IMHO they make great headphone amps. There is no speaker efficient enough to make a Set amp produce an undistorted 95 db comfortably which is around what is measure in most small jazz clubs. I suppose if you live in an attached condo and can't disturb the neighbors they are fine. Seigan, a 100 watt tube amp clips at exactly the same place as a 100 watt SS amp. But tube amps clip softly while SS amps clip hard. The Tube amp sounds better clipping than the SS amp which may be the major cause of the attraction of tube amps. The tube amp will seem to play louder. But any amp that is not clipping will sound better than an amp that is. You get an amp to POWER your loudspeakers. Power is everything. The more you can afford the better, Tube or SS.
I'm not an engineer but it's my understanding that if 2 amps are of equal gain they'll be equally loud at equal wattage output. Meaning that you'll likely be ok with a lower wattage tube amp vs a ss that you rarely ever use all those reaerve watts
I liked my tube amp but it didn't drive my woofers as well as a SS amp does. I tried the different ohm settings and the 4 ohm was better than the 8 ohm, still wasn't to my liking. Amp had 4-kt120 tubes.
But I agree that for most speakers of 80 - 90 db sensitivity a good 50 - 100 wpc amp (SS or tube) will be more useful! Beyond that, more power is just wasted in the typical home at average listening levels!
Roberjerman, I will agree that if you never play louder than 85 db you do not need much power and I had a very good audiophile friend in Miami who never did and he use to sit right on top of his Dalquist speakers wearing them almost like a set of headphones. His wife who was a sweetheart had relegated him to the smallest room in the house. I bought my Heresy's back in, lets see I was 17 at the time so that would be 1971. I think that was just when they were released. In college I use to drive the crap out of them with a Phase Linear 700. I use a YFE YF 20 sound level meter which is a fun piece to have and not very expensive. I can adjust my volume very accurately when AB ing equipment using a sine wave. At 100 db you are for certain clipping your amp. SETs do clip very gracefully which is one of the attractions and Herey's are very efficient. When I first got mine I had a Dynaco Stereo 70 which for my teenage ears did not play loudly enough. But, I had come from AR 2Ax speakers so the Heresy's were a big improvement. Subs would have helped but we did not have them back then. If your SETs do the job for you that is wonderful. They certainly can sound beautiful but I am the crazy maniac who wants the drum set in my media room and that requires serious power and subs even with efficient systems. Peaks can easily require 10 times the power which again is one of the big draws of tube amps. They clip more gracefully which allows them to play louder before getting obnoxious.
AR 9's are bi ampable. Consider using tube for the mid and upper end and SS down low. Or.. Pair your SS amp with a tube pre amp. There are some nice ones in your price range. It can be a very good combination.
Frankly I would change you speakers to more efficient speakers. You might be amazed by the quality of modern speakers. Also the posting on the liveliness of tube amps is right on the mark. No solid state amp can equal the sound of tubes, that is the presence, sound layering and ability sound good at low volume levels.
@mijostyn : The Heresy's date from 1957 (same as Quad's). I think they sound even better with my First Watt F5 (25wpc). Still, for dinosaurs they are certainly capable of rocking out - try a nice vinyl copy of the Stones Let It Bleed!
@browndt: "No solid state amp can equal the sound of tubes ..." NONSENSE! I'm sure that Nelson Pass would agree with me that either type of device is capable of accurate reproduction of a musical waveform!
@bestbaker, as mentioned earlier the speakers are spec’d at 87 db/1 watt/1 meter, with an impedance of 4 ohms nominal and 3.2 ohms minimum. A brochure I found at HiFiEngine.com indicates that an input of 8 watts will produce 96 db at 1 meter, which is precisely consistent with the 87 db/1 watt number. I couldn’t find an impedance curve for the speaker, though, which would indicate how its impedance varies over the frequency range.
**If** the 87 db and 96 db specs are accurate (and speaker efficiency and sensitivity specs are often optimistic by a few db) it can be calculated that at a listening distance of say 12 feet in a medium to moderately large size room two such speakers driven by say 50 watts will be capable of generating an SPL at the listening position that is in the mid to upper 90s. That will be enough volume for most listeners with most or all of their recordings, but it will certainly not be enough for some listeners with some recordings. Especially recordings having particularly wide dynamic range (i.e., a large **difference** in volume between the loudest notes and the softest notes), such as many well engineered minimally compressed classical symphonic recordings.
What may be a more significant concern, though, (which Millercarbon alluded to in his post early in this thread) is impedance compatibility. The speakers were presumably designed with the expectation that they would usually be driven with solid state amplification, and solid state amplifiers almost always have output impedances that are a tiny fraction of an ohm. While the output impedance of tube amps varies widely, and can be anywhere from somewhat less than an ohm to several ohms or more. If the impedance of the speaker varies significantly over the frequency range (and it probably does, although as I mentioned I couldn’t find an impedance curve for it), the interaction of that relatively high amplifier output impedance with the speaker’s impedance variations is likely to have unpredictable tonal consequences that were not intended by the designer.
To minimize that you would want to choose a tube amp having relatively low output impedance, which correspondingly means a damping factor which is relatively high (for a tube amp). I would certainly not feel comfortable choosing an amp having a damping factor of less than say 8, and many and probably most tube amps do not meet that requirement.
Makers of tube amps having relatively low output impedance/high damping factors include Audio Research, Music Reference, McIntosh, and possibly various VAC models which provide a 2 ohm output tap. However finding an amp which provides adequate power, low output impedance/relatively high damping factor, high quality sonics, and meets your stated budget, is likely to be a challenge. Personally I would follow the advice of those who recommended staying with solid state.
Efficiency is a much more useful spec when dealing with tube amplifiers as tube amps don't double power as impedance is halved.
The bottom line is if you want satisfying sound pressure *and* you want tubes, you are far better off getting a speaker that is not so inefficient!
Sanders biases his arguments towards his own amps which are admittedly
great values in high powered amps. Yes, high powered tube amps waste a
lot more energy as heat than an AB SS amp. He is also expressing his
opinion with a bias toward driving his electrostatic speakers. He
dismisses OTL amps off hand. He is right that you need to use a lot of
tubes to reduce the impedance of the output section but once you do so
they are every bit as effective at driving electrostats as SS amps.
@mijostyn ESLs don't obey the same rules of loudspeaker operation as conventional box speakers; no doubt because a box isn't involved for starters :) As a result, to make them more compatible with solid state (as otherwise ESLs are *far* more compatible with tubes), Sanders made his speakers fairly low impedance, just like Martin Logan. This results in impedances that are south of 1 ohm at the upper range of the speaker. For more on how this works seehttp://www.atma-sphere.com/Resources/Paradigms_in_Amplifier_Design.php
In a nutshell since your speakers are 4 ohms the efficiency is 3dB less than the stated 87dB.
Hi Ralph (Atmasphere),
In this particular case the 87 db spec is stated to be based on an input of 1 watt, rather than on an input of 2.83 volts. Also, as I mentioned in my previous post the brochure for the speaker states that an input of 8 watts results in an SPL of 96 db at 1 meter, which is consistent with 87 db/1 watt/1 meter. So if those numbers are accurate the efficiency is 87 db, rather than 84 db.
VTL 300 Deluxe would work if you want tubes. Personally my AR-90s never really sounded that good with tubes. What you need is high current SS. I like Threshold myself. Using a 550E at the moment but my 300 worked well. I'd love a pair of SA/1 but need the coin.
Atmasphere, thanx for the article. For certain humans are extraordinarily change resistant. That is an unusual perception for an engineer. Those that embrace change are the pioneers like Tesla, Ford, Musk and others less well known. Too bad non of them are politicians. Under the power paradigm you want speakers of steady impedance and relatively high efficiency. How does Soundlabs achieve this with an electrostatic loudspeaker. My Acoustats drop perilously low at high frequencies. I had to put a1 ohm series resister on the primary to prevent my amps from overheating. I removed the stock transformer drive and put one large 1:100 Sowter transformer on them resulting in this behavior. Conversely I always shied away from McIntosh amplifiers because they used transformers. I am not sure how they use feedback but it would appear they applying the objectivity principle. I am sure you prefer not to make comments on other companies amplifiers but how do you think this affects their sound versus standard voltage driven SS amplifiers. My final question is, how do you keep your amps power driven without transformers. I have long forgotten what boxes sound like;-)
Atmasphere, one more series of questions. The Sensitivity measurement in db/1watt/1meter, is this measured with white noise? Does this really tell you how the speaker will perform with music? Is "music sensitivity" frequency dependent. I roll off my speakers at 125 Hz 48 db/oct. My assumption has always been that the efficiency of the speaker increases because it would require less power to reach a certain volume than if I ran it full range. Is the correct or am I deluding myself? The sensitivity has not changed but efficiency increases? The Soundlab Magestic 845 has a senstivity of 89db/1watt/1meter. This means that it would take 128 watts to get to 110 db. This is the loudest playing music I would ever go. The MA 2 has sufficient power to do this. How would the MA 3 sound better. Some would argue that music being dynamic has peaks that go much higher than the steady state volume requiring much more power to handle without clipping. Music obviously has peaks like the snap of a snare drum but are these peaks that much higher? The power required does increase geometrically. The MA 3 will go about 4 db louder than the MA 2. Does this headroom make a difference?
In this particular case the 87 db spec is stated to be based on an input of 1 watt, rather than on an input of 2.83 volts. Also, as I mentioned in my previous post the brochure for the speaker states that an input of 8 watts results in an SPL of 96 db at 1 meter, which is consistent with 87 db/1 watt/1 meter. So if those numbers are accurate the efficiency is 87 db, rather than 84 db.
@almarg
Apparently it matters where you look. The specs I found stated 4 ohms and 87 dB Sensitivity; since the sensitivity spec is a voltage spec and not power, this translates to an efficiency as I stated. I’ve seen speaker manufacturers confuse efficiency and sensitivity before; is this one of those cases?
Under the power paradigm you want speakers of steady impedance and relatively high efficiency. How does Soundlabs achieve this with an electrostatic loudspeaker. My Acoustats drop perilously low at high frequencies.
@mijostyn Actually a steady impedance is not required of either paradigm. What is required is best put as the designer’s intention- and the behavior of the technology. In the case of ESLs, the impedance curve is based on a capacitance rather than a driver in a box (with its consequential resonance). On this account, ESLs have an impedance curve that essentially decreases as frequency increases. The Sound Lab for example is about 32 ohms in the bass but only 1.5-3.0 ohms (depending on the position of the Brilliance control) at 20KHz. The impedance curve of a box speaker maps out its efficiency with respect to frequency; with an ESL the efficiency remains constant despite its impedance.
One sign of a speaker that is a Power Paradigm device is that it will have controls in the crossover- like you see in the Sound Lab, but also like you see in vintage speakers like Altec, JBL, KLH and so on. These controls are not there to adjust the speaker to the room (although they are often used that way) they are there to adjust the speaker to the voltage response of the amplifier, which is an unknown. In the Voltage Paradigm the voltage response is a given; the idea was pioneered by MacIntosh and ElectroVoice in the late 1950s to assist with plug and play. The problem is to do so audible distortion in the form of brightness is usually introduced by the operation of the feedback loop in the amplifier, and one has to come to terms with the simple fact that no loudspeaker is actually flat in frequency response- so getting ’flat response’ is a bit of a red herring.
Add to that the fact that the ear/brain system interprets distortion as tonality (which is why we perceive the distortion added by feedback as brightness), often favoring it over actual frequency response, and you have a situation where you can often achieve greater neutrality without feedback. Crazy world, but we really can’t change how our ears perceive sound except by damaging them. So it seems pragmatic to come up with engineering solutions that take the human ear/brain hearing perceptual rules into account rather than ignoring them!
I would like to add, compare a high power amp to a high horsepower car. Even at lower operating levels you can feel the power that is available. By this I mean it is much more responsive and effortless in its presentation.
Atmasphere, I am certainly a believer in considering how the sensitivity of our ears changes with volume as were scientists long ago. Harvey Fletcher and Wilden Munson wrote their famous paper back in 1933. Loudness correction was a standard feature in preamps back in the day. The problem was that only one correction curve could be used which would only be accurate at one volume level. My processor uses a set of 6 curves pertaining to specific volume levels. The processor automatically blends from one curve to the next as volume increases, Dynamic loudness correction. The end result is that the music sounds the same regardless of volume. Bass and treble are automatically cut as volume increases. Under these circumstances I think distortion/clipping is more obvious as it stands apart from the high frequencies of the music. It also makes listening at high volumes magically comfortable. Violins and female voices do not cut your throat. The processor also does room control. IMHO the importance of room control is not in obtaining a flat frequency response as flat sounds terrible at most volume levels it is in obtaining exactly equal frequency response in both channels. The end result being laser imagining as frequencies don't shift between speakers. Any speaker's frequency response will change with position as well as two speakers of the same model will have slightly different frequency response. This technology is starting to become available in various iterations and I expect it will drift down to lower price points. None of the currently available units have dynamic loudness correction.
My understanding is that the concept of “bandwidth” is very important. Perhaps more important for tube amps than solid state. But I have a First Watt SIT-3 which is a low watt solid state amp. It apparently has some bandwidth to it because it drives my Magico A3s well. They have a sensitivity of 88dB, an impedance of 4 ohms and recommended minimum power of 50 watts. The SIT-3 drives them just as well as my Bryston 4B3, which has a lot more power. But what I would like to know from the group is: how is bandwidth measured? How do you calculate bandwidth? Thanks.
I am driving 85 dB sensitivity speakers with 200 WPC of pure
analogue
tube power using 8 KT150s. I can drive these to 98dBA spl with little effort and NO clipping and more to go. It sounds better than the comparable powered SS amp that I replaced.
It's most likely been already covered but a watt is a watt whether it is sand or glass. All other factors will influence how amps work in their installations but a Watt is the same no matter where it comes from.
May want to consider a solid state amplifier with a little more ‘meat on the bones’ to emulate (75% or so) tube sound but maintain the high damping factor and needed power. Consider used GamuT D200 or possibly older Clayton Audio amplifier. Both amps are built to last.
As others have said, tube amps provide a more usable power band than most solid state amps. I've been in audio for over 40 years, and have listened to countless amps, and of this I have no doubt. Another point on most tube amps is that the output transformers allow these amps to deal with complex loads quite well. Sonically, I have always found tube amps to be less fatiguing in the mids and highs.
That said, the tradeoff is the low end. AR9s, even with a massive tube amp, will be soft in the bottom end. This is the biggest tradeoff in my view. That, and the dynamic compression that occurs at higher volume on tube amps, will lead to a choice. If recreating the energy of a concert, with gut punching bass is what you're looking for, best in class solid state is hard to beat.
Roberjerman, I went back and looked at the Heresy's timeline. It does date back to 1957 but it was called the H 700. It was given the Heresy name with an update in 1972 which was probably the year I got them as they were marketed at the time as new speakers. The K horn is the longest running production speaker of all time! I remember listen to them at the store I eventually got the Heresys at. They were being powered by Marantz Model 9 mono amplifiers and a Model 7C preamp. The turntable was a Thorens TD 124 with an SME arm. I don't remember the cartridge. That was the absolute State of the Art at the time. It had no problem doing realistic volume levels.
My understanding is that the concept of “bandwidth” is very important. Perhaps more important for tube amps than solid state. But I have a First Watt SIT-3 which is a low watt solid state amp. It apparently has some bandwidth to it because it drives my Magico A3s well. They have a sensitivity of 88dB, an impedance of 4 ohms and recommended minimum power of 50 watts. The SIT-3 drives them just as well as my Bryston 4B3, which has a lot more power. But what I would like to know from the group is: how is bandwidth measured? How do you calculate bandwidth?
Bandwidth is important to keep phase shift at a minimum. To this end, phase shift is minimized if bandwidth is 10x the maximum frequency to be amplified (20Hz, so 200KHz required) and also 1/10th the lowest frequency to be amplified (20Hz, so 2Hz response required). Bandwidth is measured by either a sine wave or square wave; with a sine wave the signal is applied to the circuit and the output observed to be within usually + or - 1/2dB to be considered ’flat’; with a squarewave rounding of the edges can be seen to show a rolloff at high freqencies and tilt on the top of the squarewave shows a rolloff at low frequencies. This is fairly easy for transistor amps, and there are tube amps that meet the ’2Hz-200KHz’ requirement too, but to my knowledge they are all OTLs (Output TransformerLess).
Keeping phase shift linear has to benefits: more accurate presentation of the soundstage and more accurate presentation of tonality. As an example of the latter, if there is a rolloff at 10Hz, phase shift will cause a lack of impact up to about 100Hz despite the amp measuring flat to 20Hz on the bench. This is why if there is a problem at 50KHz it can often be heard as well, since phase shift artifacts will exist down to 5KHz. Again, this will be interpreted by the ear as a tonality.
So one takeaway: three things affect tonality: actual frequency response (which is different from bandwidth), distortion and phase shift.
The tubes vs SS discussion should focus more on the type of music one prefers rather than the technical merits of each amp. I have multiple tube and SS amps that I interchange frequently. If you primarily listen to Jazz, voice, acoustic music of any kind there is nothing better than a quality tube amp.
The only time I would caution someone about moving toward tubes is if they primarily / exclusively listen to rock & roll at higher volumes. i don’t feel the benefits of tubes are realized in that case. I prefer listening to that type of R&R music on my SS amps. But that being said, most guitar amps use the EL34 tubes so when I listen to earlier R&R with guitar emphasis they sound more live on my EL34 amp.
The reason tube watts seem louder than SS is not because tube watts are more "powerful" but because you can listen to tube amps louder than SS without as much fatigue. The listenable / enjoyable wattage range of tube amps is greater than an equal SS amp.
I would also recommend an EL34 tube amp as a starter / first tube amp because the EL34 really hits the sweet spot of tubes. If budget is any consideration, you can buy a quality used one very reasonably and latter upgrade to a new tube amp if you find that tubes are for you. That is what I did and got a very good price on a Cary V12R EL34 amp and then latter bought a new tube amp. I still own the V12R and enjoy it daily.
I have two listening systems one with difficult to drive speakers. I bi-amp them both with a tube amp on top and a SS amp on the bottom pushing the woofers. This works very well with difficult speakers that demand more power.
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