what is your opinion ?

Altecs have controlled directivity in the mids and highs. Your panel speakers need to use the wall behind them to work properly- that needs to be about 5 feet minimum and you can’t have side walls too close or the reflections will mess with the soundstage and make things sound harsher.

The Altecs are likely 16 ohms- all amps make less distortion into higher impedances, and your tube amps tend to make lower ordered harmonic distortion, which is far less audible to the ear than the higher ordered harmonics that are typical of most solid state amps. Plus they are efficient enough to properly take advantage of the very lower power of your SETs. This all works in your favor. In order to get the most out of SETs, they should not be driven past about 20% of their total power, as those higher ordered harmonics start to show up, making them sound loud. A good stereo won’t sound loud even when it is!

There are ways to improve what you are hearing even further. In the Altecs the horn tends to resonate due to its construction; if you can damp it with some proper extensional damping materials it will get smoother. But the horn itself has issues since it was designed (and fairly well for the time) before computer optimization. Modern horns can be smoother and more detailed as a result.


Believe it or not there are also modern tube amps that are more revealing than the SETs on Altecs. The technology has advanced...


BTW the solid state amps you were playing very likely had insufficient Gain Bandwidth Product to really allow them to be musical. Gain Bandwidth Product is a tricky bit to explain, but in a nutshell it means that while you might have adequate feedback to control distortion at low frequencies, you don’t at high frequencies, which causes the latter to be harsher. This has been a problem with all amplifiers over the last 50 years, including tubes, but because tube amps tend to make lower ordered harmonics they tend to sound smoother. This has fueled the tubes vs transistor debate for the last 50-60 years! But its really not about tubes, its about getting enough gain bandwidth product to really allow you to run enough feedback, and that is a real trick- its really only become practically possible fairly recently.

@sabih,

"my question is why these old school design audio sounds nearer to reality ?"

"or maybe we humans are we trying to re invent the wheel again ?"


There's no surprise here as many still hold those vintage designs such as your Altecs or Apogee's in high regard. Are they easily beaten by today's designs?
I think not.

I remember once reading an interview where the founder of Naim Audio, Julian Vereker, was asked what system he would listen to, if not his own.

His reply was, a vintage Quad amplifier! 

There does seem to be a lot of 'reinventing the wheel' going on in audio, hence it's all too easy to 'climb' the ladder only to find yourself eventually back near the bottom.

The single biggest improvement I've noticed in over 30 years is the quality of budget speakers. Some of the stuff made by companies like Dayton Audio, Adam, Edifier and Q Acoustics must be light years ahead of budget designs of the 1980s.

This seems to be a heavily competitive area of the market and has no doubt benefited from advances in computer design.

Yes, you are lucky to have a dedicated music room. Glad you're enjoying it.

Thanks , I  would really like to hear from other music lovers and Audiphiles, their experiences which regards SET amplifiers and horns and other high sensivity speakers,  as a retired BBC Sound engineer ,once I had a opportunity to good chat  with RIP Don Garber asked him what is the best system, his respond was ,,,The  Best system is the  one you are really enjoying listening to .

I run horn speakers and I've run SETs on them many times. But I prefer an OTL on them as it has obviously wider bandwidth, lower distortion, greater detail, etc. No going back.

I just recently acquired what to me is a fairly unique amplifier, a 3C24 amp that's giving me the best, most enjoyable sound I've ever heard with my Tannoy HPD 315 custom built speakers.

This amp was built for me by Paul Birkeland, designer for Bottlehead Industries.

This is in my living (listening room) in the home I have lived in for twenty seven years, where I have tried quite a few amps over the years. These being mostly solid state, but I was enticed by the likes of the late Art Dudley to try tube amp designs. I am not going back to solid state ever again. I've tried VAC (PA 35.35, and a very nice sounding Audio Assemblies SET 300B, but my new 3C24 is, and will remain, the best amp for my room and speakers. That's something, in my book.

Maybe Ralph may want to comment on how the 3C24 would match with your Altecs.

Best regards to all,
Dan