Expensive Commercial Amps

[Bryan]

Hey guys,

So, I was a little bored this morning, and I got to thinking about the commercial value of production amplifiers...

So, what are the most expensive TUBE amps you can think of, and what do you think the average cost to clone them would be (without purchasing the original to reverse engineer of course)?


Also, what is the most power you can get from a SET, if you want to go "all out". I've seen ratings in the 50-70 watts, and that seems quite high. Is is possible to get 100W from a SET?

What are the alternatives to tubes like the 211 and 845 for high power SETS?

Just hungry for food for thought!

Thanks,

Bryan

[Alastair E]

Ive been doing some experiments with the 811A but thats a smaller tube than the ones you mention--Works very well at the mo in P-P mode though..............

Take a quick look at George Anderson's Tubelabs, Hes been doing some experiments will the 833, a LARGE triode transmitting tube. He got something like 200W before his PSU sagged and limitted his power, and with quite low distortion too!

http://www.tubelab.com/833SE.htm


I think the limitting factor for power on the SET, is the cost of the PSU components (high voltage/current) and the HUGE amount of heat generated!
There are some VERY large glass triodes out there if you search around!--Ive got a triode, Its 18 inches tall, and four inches in diameter Massive thing, but its got O/C heater so no experiments with it! Guess one of those would give some power, Dont know the number, its so old and used its long gone!! Nice display piece though...........

[Sherman]

I'm too much of a newbie to answer the questions regarding SET power but in poking around over the past couple years I've seen some pretty expensive amps out there.

Check this site- http://www.electronluv.com/index.html

for some expensive hardware. Of course these are sculptures as well as working amps.

[Brett]

Originally posted by Bryan
Hey guys,

So, I was a little bored this morning, and I got to thinking about the commercial value of production amplifiers...

So, what are the most expensive TUBE amps you can think of, and what do you think the average cost to clone them would be (without purchasing the original to reverse engineer of course)?

You're looking at it the wrong way. There are amp designs out there that you can make DIY, that most manufacturers wouldn't be game to for a lot of commercial reasons, eg size, weight, costs, availability of tube types etc. Some examples I can think of are Lynn Olson's Amity, Steven Robinson's SuperAmity and the partial (plate to plate) feedback amps from Gary Pimm.
Based on a lot of what I've heard in commercial amps, I think most if not all can be bettered by a DIYer with time and dedication and a whole lot less money.

When manufacturing, about 20% of the final RRP is component costs, but that can vary. Manufacturers with some volume to their lines, eg Audio Research will be able to get much larger volume discounts from suppliers and have transformers made to spec for much lower cost that you or I could from a manufacturer, one off. Or we may need to use a couple of transformers to get the final required secondaries. Some parts wouldn't be available in the quantities a company like AR would need either, such as Magnequest cobalt O/P transformers.

[amperex]

I believe the limiting factor with regard to Class A SE is the audio transformer. Two routes is high voltages or high current. Very high voltages requires lots of windings & primary impedances above 10K adding to leakage. A large lot of parallel connected tubes is reported to add smearing to the sonics.

Even 70-watts RMS is a lot of power & is not a difficult task for a large transmitter type triode.

[HFGuy]

833 or gm100 is the largest SET amps ive seen. Both are capable of exceeding 100w.



P.S.

No such thing as RMS power

[Geek]

Originally posted by HFGuy
833 or gm100 is the largest SET amps ive seen. Both are capable of exceeding 100w.

There's a European one out (can't remember the URL) based on the 4-1000A transmitting tetrode. Monoblock on oak selling for $30,000 USD/ea.

It wasn't pushed though - they rated it at 10 watts output. That would mean they ran the 4-1000 at ~1/25 what they could have.

[tubelab.com]

The true costs in producing comercial amps add up real quickly. If you were to figure in all the overhead involved in producing a comercial product I would think that the 20% number is too high. If you had an original amplifier design (not a copy of an existing product) with $100 worth of parts in it, it would sell for at least $750 to $1000, once you figure all the costs of producing, engineering, advertising, insuring, and selling that amplifier. This in not even counting the cost of getting safety (UL in the USA) agency aproval in EVERY country that you intend to sell it in. Now those $100 worth of parts will cost the average DIYer about $150 TO $200 since only one amp is being built.

Yes I have built an SE amp that puts out over 200 watts RMS. The limiting factor in big SE amps is definitely the output transformer. Make it big enough to get high power at low frequencies, and it has too much winding capacitance to do the high frequencies. I had a custom transformer made that works well for a guitar amp, but doesn't quite cover the whole Hi - Fi range. The 212 watts that I was getting was measured at 1 KHz. I am going to try again with Hammond 1642SE's. The results will be on the web site.

[HFGuy]

At what power point do we start to question our speaker selection ??? Seems to me to be a squeeze out of medium effec speakers. The trend seems to be going either high effec > 100dB/w/m or very low < 85dB/w/m. There are advantages to both sides but why doesnt there seem to be any middle road choices ?? I dont think you'll find too many high power SET amps because of the safety issues. Look at the safety warning on grocery bag forget equipment that runs 2kV.

[tubelab.com]

I agree, going from 86db speakers to 96db speakers is the same loudness increase as going from a 10 watt amp to a 100 watt amp. Unfortunately I have a small listening room, which is also the lab, and I have 86db speakers. My favorite amp ( Tubelab SE ) puts out 2 watts per channel with 45's. I am considering new speakers but given the size constraints the best I am going to find in my price range is about 95db. I was considering the Klipsch RB-35 but the local dealer wasn't interested in spending the time to let me try them with MY amp for ONLY a $550 sale.

My infatuation with BIG amplifiers has more to do with a desire to build something different. And the fact that I have 24 833A tubes. I had some 4-1000's but given the high plate impedance I know that transformers would be impossible, so they went on Ebay.