Discussion
selym said:
I use a Chinese valve pre-amp for phono duties. You need to determine if you like the 'valve sound'. Borrow one and give it some serious consideration.
My mate was trying to persuade me to go with a chinese amp. The price range on eBay/alibaba is immense so it's impossible to choose.I had a World Audio Design KEL84 amp for a while which I really liked. A rather different sound compared to a transistor amp, good clarity and surprisingly fast and punchy.
Outputs are typically low so you'll need some speakers which are reasonably easy to drive - at least 90db rating and a nominal 8 Ohm impedance whould be a good starting point. I used a pair of Rega RS1s to good effect. That said, people seem to believe that valve watts are more effective than transistor watts.
You'll also need to be prepared to give it some room to breath as they run surprisingly hot.
If you can get around the pratical considerations I'd thoroughly recommend listening to one. Now we have more space I intend to buy another when I can.
Outputs are typically low so you'll need some speakers which are reasonably easy to drive - at least 90db rating and a nominal 8 Ohm impedance whould be a good starting point. I used a pair of Rega RS1s to good effect. That said, people seem to believe that valve watts are more effective than transistor watts.
You'll also need to be prepared to give it some room to breath as they run surprisingly hot.
If you can get around the pratical considerations I'd thoroughly recommend listening to one. Now we have more space I intend to buy another when I can.
I have used an Audio Innovations S500 Since 1992. It's rated at 25Watts per channel and works really well. It is considered the "classic" British Valve amp of it's time. Generally they sell for between £450 and £700 depending on the Power Supply and Valve's fitted. Plenty of inputs and will support a MM cartridge on a turntable. The New Chinese amps are a mixed bunch. Those built for British companies tend to be a safer bet. The Main "British" players still going are Esoteric Audio Research, (EAR/Yoshino). Audio Note and "The Affordable Valve Company" whose amps are sort of Chinese but sorted out. There are plenty of Older makers and as the Amps are usually based on Circuits from the 1950's and 60's they are usually easy to fix. As said a lot of the Amps are considered "low" power. The Audio Note OTO is a great amp but only produces 10 to 12 watts per channel whereas the Affordable have 40watts but does not sound as good. Personally I would look for a amp speaker combination that sounds good to you. And take your time over the listening process.
Roadster25 said:
I had a World Audio Design KEL84 amp for a while which I really liked. A rather different sound compared to a transistor amp, good clarity and surprisingly fast and punchy.
Outputs are typically low so you'll need some speakers which are reasonably easy to drive - at least 90db rating and a nominal 8 Ohm impedance whould be a good starting point. I used a pair of Rega RS1s to good effect. That said, people seem to believe that valve watts are more effective than transistor watts.
You'll also need to be prepared to give it some room to breath as they run surprisingly hot.
If you can get around the pratical considerations I'd thoroughly recommend listening to one. Now we have more space I intend to buy another when I can.
I've had a fair bit of valve kit over the years - Pre's from Copland, Quad and Audio Research, and Powers from Quad, McIntosh and Audio Research.Outputs are typically low so you'll need some speakers which are reasonably easy to drive - at least 90db rating and a nominal 8 Ohm impedance whould be a good starting point. I used a pair of Rega RS1s to good effect. That said, people seem to believe that valve watts are more effective than transistor watts.
You'll also need to be prepared to give it some room to breath as they run surprisingly hot.
If you can get around the pratical considerations I'd thoroughly recommend listening to one. Now we have more space I intend to buy another when I can.
I'm not sure about this stuff that there is a valve 'sound' which is different from a 'transistor' sound. There was years and years ago when valves tended to sound a bit warmer than transistors, but things have moved on a bit, at least in terms of solid state amplifier design. Lots of the modern valve designs date back to the fifties - the McIntosh 275 I had certainly did - but the modern ones are better built with high quality components.
The goal of any hi-fi system is to produce a sound that's faithful to the original recording, and IME, a good amplifier be it valve or solid state will do that, and you wouldn't necessarily be able to tell the difference between them. Again, in my experience, where the valve amps might just shade it is in the presentation of the music. I had a Quad valve set up for a while driving a pair of Quad electrostatics, and the sound staging with that equipment was just awesome. It was, however, an extremely domestically unfriendly set up, and SWMBO made me get rid of the speakers.
None of the valve amps I had would have had a problem driving low efficiency speakers, although it is true that with a very low output amplifier you might have to take that into account.
And it is true that some valve amplifier designs run very, very hot. Others however run quite cool. The hotter a valve amplifier runs the shorter the tube life tends to be though.
I moved away from valve amplification precisely because of valve life. The last ARC power amp I had used 8 (matched) KT120 tubes at about £40 a pop each. The life of a power tube can be as little as a couple of thousand hours, which is maybe 3 months of continuous use. But no-one I know leaves a valve amplifier switched on 24/7, not only because it drastically shortens the life of the tubes, but because there is a fire risk if one decides to go bang when you aren't around. Some die gracefully, some don't.
There are other disadvantages to valve amplification. They tend to need lots of space, not only because they are physically large, but also because they need space around them to allow for air flow to soak away the heat generated. They also tend to be heavy. Th last two I had weighed in at over 30Kg each, which isn't funny if your listening room is on the top floor of the house and you have to hump them up three flights of stairs.
Anyway. I now have a Naim based system, which is left on 24 hours a day, so no waiting around while the system warms up. I still have a valve phono stage though - a slightly modified EAR 834P with some Telefunken valves in it dating from the 1950's.
Would I go back to valve based pre-power combo? Possibly
For all the people who seay any competently designed amplifier should sound the same, in reality there's an enormous spread of characteristics between them with no hard and fast rules about what valves or solid state will sound like.
There is no 'valve sound' as such (and neither is there a 'solid state' signature). A valve amp that comes across all warm and cuddly (and gutless) probably has inadequate output transformers, and a transistor amp that puts a hard 'glaze' on the sound probably has an operating point well into Class B and lots of global feedback.
There's pentode/tetrode amplifiers and triode amplifiers, the former category can work in ultralinear or triode modus, there are Class AB, Class A push/pull and single ended amps - all design choices that have a big influence on the end result.
The good thing about valves is that, being more linear amplification devices than semiconductors, they can operate in really simple circuits which retains an immediacy and sense of 'being there' in the music reproduction that is very hard to achieve with solid state amps.
The downside of valves (apart from wear and hum/microphony issues) is that they need anoutput transformer in the signal path, the quality (and price!) of which for 95% determines the sound quality of the amplifier. Therefore the cheaper valve amps can be really charming in a relatively modest set up, but are ultimately limited which will show up when paired with wide bandwidth, highly dynamic speakers.
In general, the 'purer' the design in terms of SQ, the more difficulties the amplifier will have driving 'real world' speaker loads and the result can be a sound that you can't really call 'hi fi' anymore (some folks will like it, though)!
My feeling is that if you want to go valves, you need to take a long hard look at your speakers. Are they really efficient (high sensitivity = high sound pressure level for each Watt) with a benign impedance curve? Then a simple, well designed valve amplfier could well be what you're after.
If not, there will still be valve amplifiers that will work with your speakers but they will tend to be expensive and complicated, negating the chief advantage of valve amplification. In that case I'd either start choosing different speakers or not bother.
There is no 'valve sound' as such (and neither is there a 'solid state' signature). A valve amp that comes across all warm and cuddly (and gutless) probably has inadequate output transformers, and a transistor amp that puts a hard 'glaze' on the sound probably has an operating point well into Class B and lots of global feedback.
There's pentode/tetrode amplifiers and triode amplifiers, the former category can work in ultralinear or triode modus, there are Class AB, Class A push/pull and single ended amps - all design choices that have a big influence on the end result.
The good thing about valves is that, being more linear amplification devices than semiconductors, they can operate in really simple circuits which retains an immediacy and sense of 'being there' in the music reproduction that is very hard to achieve with solid state amps.
The downside of valves (apart from wear and hum/microphony issues) is that they need anoutput transformer in the signal path, the quality (and price!) of which for 95% determines the sound quality of the amplifier. Therefore the cheaper valve amps can be really charming in a relatively modest set up, but are ultimately limited which will show up when paired with wide bandwidth, highly dynamic speakers.
In general, the 'purer' the design in terms of SQ, the more difficulties the amplifier will have driving 'real world' speaker loads and the result can be a sound that you can't really call 'hi fi' anymore (some folks will like it, though)!
My feeling is that if you want to go valves, you need to take a long hard look at your speakers. Are they really efficient (high sensitivity = high sound pressure level for each Watt) with a benign impedance curve? Then a simple, well designed valve amplfier could well be what you're after.
If not, there will still be valve amplifiers that will work with your speakers but they will tend to be expensive and complicated, negating the chief advantage of valve amplification. In that case I'd either start choosing different speakers or not bother.
Edited by 900T-R on Tuesday 28th October 12:24
In answer to the OPs question , yes quite possibly but you won't know til you try it.
All of the above caviats apply when looking at amps. A valve heats like an old light bulb (very inefficient at it's intended job) so will always be hotter than a transistor amp. Valve amps need maintenance and replacement valves so long term cost is an issue especially if you like to change them to keep the "best" sound and use matched sets ! Valve circuits are simple and most designed over 50 years ago. Performance is based on the quality of the components (transformers) so you can happily buy a 50 year old amp , change the valves, restistors and capacitors and have an amp that will compete well with new ones
All of the above caviats apply when looking at amps. A valve heats like an old light bulb (very inefficient at it's intended job) so will always be hotter than a transistor amp. Valve amps need maintenance and replacement valves so long term cost is an issue especially if you like to change them to keep the "best" sound and use matched sets ! Valve circuits are simple and most designed over 50 years ago. Performance is based on the quality of the components (transformers) so you can happily buy a 50 year old amp , change the valves, restistors and capacitors and have an amp that will compete well with new ones
I still think Valve amps have a 'sound' usually laid back and warm, If you are happy with the Cyrus which are quite lean and bright you may struggle with the 'valve sound'.
Also if you've picked the rest of the system to tone down some of the excesses of the cyrus kit, you may find a valve amp a bad fit.
Valve amps are usually low powered so may have issues driving some speakers.
Also if you've picked the rest of the system to tone down some of the excesses of the cyrus kit, you may find a valve amp a bad fit.
Valve amps are usually low powered so may have issues driving some speakers.
Edited by sparkyhx on Tuesday 28th October 14:46
nyt said:
My mate was trying to persuade me to go with a chinese amp. The price range on eBay/alibaba is immense so it's impossible to choose.
I use one of these. It was a secondhand buy and was recommended by people on one of the hi-fi forums I use. I've had a lot of fun 'tube rolling', which is modding for valves. One thing to note with Chinese kit; they won't be set up to accept 240v as standard. Buying new you will have the option to choose 240v, but mine is the 220v version. You pays your money...
sparkyhx said:
I still think Valve amps have a 'sound' usually laid back and warm
Only old-school and/or cheap Far Eastern ones, or when paired with unsuitable speakers (anything with complex crossovers and lots of drivers is a no-no, in general). Conversely, the thing that always gets me about properly executed single ended valve amps is their sheer immediacy, speed and vibrancy (they will have VERY substantial and expensive output transformers though, and even then only shine when driving sympathetic speaker loads).
Apologies to the OP for diverting off topic but some valve fans may be interested in the attached review; the reviewer appeared to be seriously impressed with the monoblock's performance relative to his single ended 300B Western Electric valve amp.
http://www.enjoythemusic.com/magazine/equipment/05...
http://www.enjoythemusic.com/magazine/equipment/05...
Crackie said:
Apologies to the OP for diverting off topic but some valve fans may be interested in the attached review; the reviewer appeared to be seriously impressed with the monoblock's performance relative to his single ended 300B Western Electric valve amp.
http://www.enjoythemusic.com/magazine/equipment/05...
Note that he doesn't specify the make of the 300B amp, just that it's got WE tubes. The amp itself could've been anything from a ch-fi Ebay special to a £60K Kondo. http://www.enjoythemusic.com/magazine/equipment/05...
As he states that his 300B amp would set him back about $4000 inc special capacitors and WE valves we can eliminate all but the cheapest. Sadly whilst price cannot be taken as a guarantee of quality there are very few exceptions in terms of giant killing cheap amps. For T class amps they are expensive, £27 on e-bay buys you a new 20w per channel amp with the same chip 
900T-R said:
The downside of valves (apart from wear and hum/microphony issues) is that they need anoutput transformer in the signal path, the quality (and price!) of which for 95% determines the sound quality of the amplifier. Therefore the cheaper valve amps can be really charming in a relatively modest set up, but are ultimately limited which will show up when paired with wide bandwidth, highly dynamic speakers.
Not totally correct. There have been several valve amplifiers built without output transformers. I had the original Acoustat X electrostatic speakers which came with a massive valve amp directly coupled to the panels.Edited by 900T-R on Tuesday 28th October 12:24
Futterman built amps in the US which again didn't have output transformers as did Glen Croft in the UK.
Multiple parallel output devices in all these amps mean you can direct couple and sound is really good, however should one output valve go down, all output valves and speakers can suffer so not without problems!
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