To be fair, I’m not expressing any opinion at all about the speakers - just sayin’ that if you feel you need a powerful valve amp then they’re perfectly do-able. Valves used to push half a megawatt of radio 4 up the twigs at Droitwich all day every day without fail, after all. And GEC had a DIY design for an 1100W audio valve amp back in 1957 (as it happens I have a copy of An Approach To Audio Frequency Amplifier Design, retired from Aston Uni’s elec eng library open on my desk right now).
I don’t have first-hand experience of VTL’s 450W monos. But the 200 WPC amp is a development from their 150 WPC version which I have had on the bench here. Really the only lunatic thing about that was the idea that 6550’s would survive in it. Everything else just amounted to a lot of rather nicely engineered normal. Once it had KT90’s in all the valve expiry trouble stopped. I heard from the owner, out of the blue, the other day. Oh dear, I thought, has a valve gone pop after a couple of years ? No. The amp is fine. But he’s now started importing Japanese vinyl and was wondering if I might be interested in a disc or three.
There is theory and there is actually owning and using them with different amps. The ATC 40s need at least 200W and the ability to drive low impedence well, otherwise you are simply not getting the best from them.
Then you need low output impedance. Not power, usually of course high output amps have many devices paralleled, and high feedback, which leads to very low output impedance, but there are exceptions, the 60w amp I built that Ian has for example has an output impedance of under 0.1ohms, and if it was an A/B amp could probably be 3-400w.
Power =/= Drive, Power(voltaqe) = Volume
And no not entirely Serge, but I have always been Serge lite
yes , were these that beautiful pair on aos ? . glad you could get them and glad they sound good . i know some on here like the mark 2 but the mark 1 sem to elicit various opinions
A few years back in my search for something that wouldn’t give me bass issues in my room I bought a pair of SCM40s.They didn’t last long. I even called ATC and asked of they had any alternative tweeter options. That went down well
They did however sound really good hooked up to a pair of Adcom monos.
Reminds me of years ago, when I was trying out speakers, I had a pair of Usher 8870s??, and I thought the tweeters were a bit hot.
They had three different pairs of tweeters, that were slightly less sensitive; the one I tried was about 1.5 DB less sensitive. Still didn’t like the speakers.
well , harbs arrived today from factory after a pretty long wait . just playing now so will feedback but bass is way more than i expected and if it continues like that the neighbours will be knocking on the door !!! hopefully it will calm down
How might the lows calm down? Not sure that is something which will happen without some form of adjustment to the signal & or removing the bass driver.
quite probably , we shall see how things go . considering i have those iso pucks and they are raised up on stands they certainly shake the floor with syriana soundtrack .
