You’re looking to buy a good vintage or second-hand amplifier, so do you go for tube (valve) or transistor?
This is a difficult question to answer.
On the face of it, tube amps are an antiquated technology with performance that is grossly inferior to modern solid-state designs:
- tubes have characteristics which affect the tonal balance of the speakers connected to them;
- the life of output tubes is pretty short, often 100s of hours (less than 500 hours in a pair of 100W mono amps I once owned);
- the heat that the tubes generate can shorten the life of internal components;
- distortion is often audible (one reason for the ‘creamy’ sweetness in older designs) and low bass can be severely distorted due to the output transformer saturating too early.
In summary, the performance of many tube amps is as if you’d added a graphic equaliser and had a good play with the adjustments.
In contrast, modern solid-state amplifiers offer inaudible distortion at all frequencies, masses of clean power and, these days, with good examples of popular models, very long and reliable lives. In all honesty, the best solid-state amplifiers can be regarded as commodities; you plug them in, switch them on and then basically forget about them as they do their job without drama. My own solid-state power amp dates from the early 1970s, it’s so ugly it has to be hidden away (it’s a pro audio unit) yet still performs very well and, sonically, just gets out of the way.
But the thing is, tube gear can look so wonderful. Glowing tubes evoke all manner of positive emotions. The best tube amps can perform very well and can have long lives, but it’s my view that such examples are few and far between. Most are poor derivatives of very old designs and perform as such. As with vintage cars, one needs to enter into an emotional relationship with the amplifier and fuss over it periodically to keep it running properly. Many valve-lovers enjoy tube rolling; fine tuning the sound with different tubes (old or new). For me, the fact that you can change the sound by replacing a tube shows the sound is coloured to varying degrees, but owners of such amps don’t care at all as it’s part of the fun and joy of ownership.
Having said all the above, I currently own a pair of rebuilt Quad II tube power amps. These were saved from a skip have been fully and sensitively rebuilt by a master craftsman. I have to say they sound is glorious, if they’re not pushed too hard, adding character to the sound that is so darned addictive. I get them out to play every so often, but couldn’t use them day-to-day as so much is missing from the musical picture they present.
Let’s compare these old Quad II power amps with Quad’s solid-state 606/707/909/QSP/Artera family of power amps dating back to 1988 or so.
The 606 family of amplifiers makes for a superb used buy, offering plenty of power for today’s music productions and a genuine ability to drive more difficult speaker loads (around 230 watts per channel into 4 ohms). They come from a different world of reproduction quality, yet the amplifiers themselves look like small breeze blocks. It’s these visual shortcomings that often result in their being ignored by the audiophile fraternity. Those that do try one in good order (most are), fall in love with them and are genuinely surprised how good they are. The Quad IIs beat them hands-down on visual charm but when it comes to reproducing modern recordings on good loudspeakers …
For the uninitiated, I’d avoid tube amps as they can be money pits if you buy incorrectly. There’s one current popular brand that is absolutely terrible and a dreadful example of the breed, yet wealthy enthusiasts buy them and use them with totally inappropriate speakers, giving a sound far removed from that intended.
So if buying vintage or used, I recommend sticking to well-reviewed, solid-state amplifiers. If you’re genuinely beguiled by the golden glow of tubes, save for something recent and properly designed. Quad and Radford immediately come to mind, along with the more expensive E.A.R. models. There is a wide range of tube amps out there (most of them imported), but many don’t live up to their alluring glow.