So it’s been a while since I first grabbed the plank of Zebrawood in my shop and envisioned it wrapped around an amplifier. That was June 13th. Here it is a little over two months later and I now actually have a functioning amplifier. I have to say I’m pretty happy with how it turned out.
Here is the new amplifier playing it’s first music last night in my office.
Now the back is still missing and the base plate isn’t installed, but she sounds really good. The bass seems fuller to me which was my main intent with this amplifier redesign however it has sacrificed none of its speed and detail. With no signal the amp is dead silent. This is good because I was a little concerned with the main power transformer so close to the right channel output transformer. Obviously I worried needlessly. The new power supply topology worked out really well.
The next step is to take all the technical data on the amplifier and compare the results to the original 6CY7. I hope to get this testing done sometime this week. However, given the extended timeline that this amp already has, I would not be surprised that it takes me longer to get the formal testing completed.
Although, even without the testing, I can tell that this amp is a solid performer.
Matt,
What a beauty. Congratulations on building the best looking amplifier I have ever seen.
Glad you like it. I’m pretty proud of getting a whole amp out of the smallish plank of zebrawood I had in my stash.
With your woodworking skills, have you ever considered building a pair of speakers?
Over the years, I have built a few kit speakers, and modified/upgraded many existing cabinets. You’d be surprised how much improvement in sound quality you can get by upgrading drivers.
I have toyed with the idea, but not seriously. I have been slowly educating myself on the basics of speaker parameters and enclosure design but it a slow slog. I will probably at some point try my hand at a set of speakers, but for now it’s a ways down the priority list.
Looks good!
The speakers look like Dayton B652’s.
What speakers do you use in your listening rooms? (Always meant to ask)
Those are actually Presidian PBS-5053 bookshelf speakers previously sold through RadioShack in the last century. Not the best in the business by any means but surprisingly good with small tube amps. I’ve also found the BIC DV62si suitable for small tube amps. These are relatively clean and sport a sensitivity of about 90dB.
Thanks,
My main listening speakers are stand mounted oak veneer “homebrew” sealed boxes with 8” Dayton Classic woofers with very old Realistic mylar dome tweeters.
Living room are modified (stuffed port) Pure Acoustics mini cabinets with Dayton 3” FR drivers – more bass than you would think a 3 incher could give.
Shop stereo has some plastic cabinet Pyles – sound ok for what they are. Nothing to write home about.
All are in the upper 80’s dB sensitivity.
And, I also have an assortment of other bookshelf speakers that I occasionally use.