• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Tube Amplifier Builder's Competition

midmoe

Member
2013-01-19 10:30 pm
hi, I wish there were and maybe something could be done about starting one. I am the guy who's built the monoblock circlotrons with 3X3-6550s in the output stage and I think I'd be able to compete. I'm in the midwest though. plus, I would need to get the high impedance systems going for any demo, but sounds fine on my modified bose 901's wired in series, with two 18" subs tied in with high impedance low passes. Also have three ribbon tweeters per side, on top of the boses. A special set of 250ohm to 8ohm transformers could be made up for max power, but I'm going for an OTL topology, so raising speaker system impedance is the way to go...What have you got? I visited to washinton state area about 7 years ago and loved it.... If the whole event could be made totally trustworthy, with bonded personel working the contest, perhaps amps could be mailed in, and uncrated , judged, then re-shipped back to owners. They would have to be ear tested with matching or same speakers of course (with power,distortion and freq. sweep equip. as final testing)...with a small entry fee to defray costs of contest....perhaps the management personel of DIY could be such individuals..??...midmoe
 
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Spriggs

Member
2012-12-10 5:16 am
hmm but there would be some issues as everything would be very subjective, cause im sure some people would just measure freq responce and distortion to give a verdict rather than listening to how musical the amp itself is. So i think some thing like what triode festival in europe has going on with their "shoot out" would work nicely but i dont want to fly to germany just to compete. A blind listening room with a 3rd party non competer handling set up and stuff and blind voting of the comunity. Something home bound in the US would be very nice. I am also unsure about the class system, as I have seen many an amp built by some no name talented person compare very well against big names, and again most of it is subjective again. Again of course no SS allowed (hahaha)
link to the triode fest shootout.
European Triode Festival - ETF2009 Shootout
 
Anyone else have some input for this? I see the competition being in Seattle or Portland with someone who could loan some very high-end source, interconnects and speakers. The competition would be officiated by three judges who would not be able to see the equipment in play as the amps were rotated through...
 
The USA is big. If this is realistic, it should be somewhere more central so those in the northeast and midwest don't have so far to go. And it should be more of a full DIY audio festival w/ sub-areas, such as the speaker shootout, and the tube shootout, and the SS shootout. Get enough interested, we could rent a big room in vegas.. that's why that place exists.
 
Here's my entry

AAIAMP_zps9dc128a9.jpg


I built it about 8 years ago. I started with a Lance Cochrane circuit and used only the best components I could find, from Soviet mil-spec teflon signal capacitors to silver wiring. A totally overbuilt power supply to the best 6SN7 type tubes I have ever heard. Hashimoto outputs and complete with Brazillian Rosewood end panels. And it runs 100% silent with no audible hum. And it weighs in at 105 pounds.

The power transformer is the large cylinder in the rear. Then the two main chokes to either side. And then the small gray pre-preamp secondary chokes in front of them with the Hashimotos on the front corners. 6J5s feeding in to 6SN7 spliters with KT88s providing the power in push-pull. Then dual 5U4-type rectifiers.

I would really like to enter this amp in a builder's competition. Now all we need to do is to arrange one :)
 
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I belong to a small group that meets occasionally in the Mid Atlantic area. We have held a couple of competitions that focus your mind by having restrictions.

The first was for a sub $200 amplifier using 6V6's as the output tubes. The amp had to built into some container that came from Ikea.

Audio ratbag: Bottleneck 6V6 Competition

The second was for a line stage under $100 using Russian tubes where the container came from Target. I'll post the link later after I reload the photos to the blog.

The third was for full range speakers under $200.
Bottlenecks Audio: Full range speaker competition

As they say about winemakers. Any decent wine maker can make great wine with the best of grapes. It takes a great wine maker to make a good wine with not the best grapes.

ray
 
Imagine picking up your amp to waist height and dropping it on concrete. That much of a drop is basically guaranteed if you ship it.

That could be part of the compition. (is it military worthy)
I'v heard you can throw a Hammond B3 out the window and when it hits the ground, plug it in and start playing, of course no one would but I think this came from the band "roadies" that throw equipment around all day long.


What about a breakout from the Rocky Mountion Audio Fest in Denver in November. We can all enjoy a few days of all kinds of audio fun.