Tubelab SPP with Parallel 6HB6
I used a SPP board from Tubelab and modified it for 6HB6’s. I added another board so I could parallel the 6HB6’s but then it sat on my bench for nearly a year. I took 2 weeks off over Christmas and built a chassis and cover for it. This is the result.
I used toroidal transformers from Amplimo, at the time the Euro and the dollar weren’t to far apart so I bought them for about what Edcor transformers would have cost and amazingly shipping was under $30. The 400mA power transformer fits nicely under the chassis.
I have only listened to it for about a half hour with my shop speakers and I’m pleased with the results.
I still have to clean up the aluminum and a few other details but it looks like the sketch I drew nearly a year ago. Its never going to be perfect like a cnc built chassis but I’m getting older and easier to please. The Japanese have a word for it Wabi-sabi “beauty that is imperfect and transient.” I’m going to go with that.
I have bought a couple different boards from George at Tubelab, they are first rate.
I had been thinking about the new 2-way Accuton speaker project, Catherine named “Tall Blondes with Beautiful Voices”, which will require 4 channels of amplification, one for each driver and I remembered the quad amplifiers from the 70’s. Especially the Sansui Quads but I had never heard of the QA-7000.
This is one one of the best looking amps I have had. The black anodized face, aluminum trimmed knobs with a small aluminum tabs on the 2 piece knobs. First class construction and detail.
The amplifier does sound pretty good but it is over 40 years old so I will be replacing all the electrolytic capacitors, the speaker relay etc. I will document this when it’s completed. I really want to use this amp with the new “Tall Blondes” but I have other amps that sound very good so we’ll see. The QA-7000 is so gorgeous though.
The QA-7000 page.
I built a prototype/test cabinet for the Accuton speaker. I like the look of stacked plywood construction. I have seen it called paralamb or translamb construction. I cut templates, then cut pieces close to size and fastened the template to them. I then used a router table and a pattern bit to cut the pieces to the template. You can see this here. It took a few days and after the glue up it turned out ok and good enough for the test cabinet but not for the final speaker.
I found a small CNC shop near me that cut the pieces for the final cabinets. He included indexing holes so everything lines up perfectly. Well worth the USD 185 it cost.
I have collected parts and designed a translam speaker cabinet for a 2-way using an Accuton C30-6-358 cell tweeter, Accuton C173-6-191E mid/woofer and 2 Accuton P173 passives. I will be using the crossover function included in Channel D’s Pure Music player.
Please stop back for progress updates.
The Opus 5.0 a modern Mullard amplifier using 2 KT88 output tubes per channel. The circuit was designed by SGregory and DIYAudio friends. I contacted him 3 years after he designed the amplifier and he told me it’s his main amp and he uses it daily. That is a stable, dependable amp. Just what I needed to satisfy my tube audio curiosity once and for all. read more…
The Jungson Hedo is a 200W per channel class A integrated amplifier. Beautiful, powerful and a joy to listen to. read more
This amp was built using Tubelab.com circuit board. This version uses type 45 triodes as outputs and mosfets for driver support.
The Telematic SA-777 from Telematic Industries.. read more
Well sort of, but a car this beautiful has to inspire something. Right?
The “Blackbirds” are in the living room and sound very good. I still haven’t had time to measure them but I will in the next few weeks. More information on the “Blackbirds look here.