Back in 2008 or 2009 I built Eli Dustman's El Cheapo amp. It's a 6 or 12AQ5 PP amp with a 12AT7 LTP driver/phase inverter. I have the schematic if anyone's interested. I wired it up wrong at first, couldn't figure it out and eventually put it aside for years. But finally with the help of some friends here I got it figured out (I'd wired on OPT wrong) and fixed it.
Meanwhile I'd ordered some Mullard 12AT7 and some RCA 6005 output tubes but didn't use them until I'd figured out what was wrong. Now that it's working reliably, I installed the Mullards and RCAs.
It was always a nice amp but now I'm hearing detail I'd never heard before. I'm quite tickled at the sound quality and very happy with the "expensive" tubes - my budget is low enough that $50 or so to re-tube an amp is a stretch. So...while I may have posted this amp a long time ago, here are a few more pics. For some reason I just LOVE that blue tint to the tubes...
Meanwhile I'd ordered some Mullard 12AT7 and some RCA 6005 output tubes but didn't use them until I'd figured out what was wrong. Now that it's working reliably, I installed the Mullards and RCAs.
It was always a nice amp but now I'm hearing detail I'd never heard before. I'm quite tickled at the sound quality and very happy with the "expensive" tubes - my budget is low enough that $50 or so to re-tube an amp is a stretch. So...while I may have posted this amp a long time ago, here are a few more pics. For some reason I just LOVE that blue tint to the tubes...
Attachments
Here are my 2 cents 2 monoblocks of 100 watts using 4 KT88 in PP, Hammond transformers, no feedback.
3 inputs, 2 of them have a tone control that can be switched off. All inputs are anode mixed together. Small switches below the vol. control can increase the gain of each input 10 dB for e.g. a microphone input.
The amps can be switched between UL mode or TRIODE mode.
3 inputs, 2 of them have a tone control that can be switched off. All inputs are anode mixed together. Small switches below the vol. control can increase the gain of each input 10 dB for e.g. a microphone input.
The amps can be switched between UL mode or TRIODE mode.
Attachments
My wooden project SE GK 71 /similar as Gubernator GK71 Wavebourn/. Output power 2 x 19.8 W without distortions. No hmmmm, no hizzz. The box from Russian tape recorder Rostov.
https://photos.google.com/album/AF1.../AF1QipOA0zW7ARyhJJBtL6rQ0pbf3gWY0Cxtr8NizUcS
https://photos.google.com/album/AF1.../AF1QipMeABfi-H4hG_MZZYmIW9_61qu3OOR_UnvzcWlW
https://photos.google.com/album/AF1.../AF1QipPJS64v1Oo3q-8lghwz2zE0waCO1PR59w-VoqiX
https://photos.google.com/album/AF1.../AF1QipOA0zW7ARyhJJBtL6rQ0pbf3gWY0Cxtr8NizUcS
https://photos.google.com/album/AF1.../AF1QipMeABfi-H4hG_MZZYmIW9_61qu3OOR_UnvzcWlW
https://photos.google.com/album/AF1.../AF1QipPJS64v1Oo3q-8lghwz2zE0waCO1PR59w-VoqiX
I don't remember if I already posted something here about my few DIY audio tube amps...
If yes, then... Apologies !
My OTL6080V5 amps - now sold to an amateur that was more crazy than me - 15WRMS 8ohms :
My 6L6UL - very compact units at 10W A class 4/8/16 ohms - on sale now :
My ULTIMATE 300B - my latest release - also very compact at 4W or 8W RMS switchable output 4/8/16 ohms :
A+!
If yes, then... Apologies !
My OTL6080V5 amps - now sold to an amateur that was more crazy than me - 15WRMS 8ohms :
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
My 6L6UL - very compact units at 10W A class 4/8/16 ohms - on sale now :
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
My ULTIMATE 300B - my latest release - also very compact at 4W or 8W RMS switchable output 4/8/16 ohms :
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
A+!
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What is the chassis you're using on the ultimate 300B. Looks like the diecast aluminum hammond boxes, but I didn't think they made them that big.
Very nice builds!
Very nice builds!
Thanks !
Well, I don't have much spare time as in the past, and moreover I'm slowly loosing my interest in audio...
These chassis came from RadioSpares. I bought them in the early 2000s. But I think that Hammond still make them (1550 series). Mine were grey epoxy coated/baked. Some links to aluminium chassis of same dimensions :
https://www.banzaimusic.com/Hammond-1550J.html
https://www.banzaimusic.com/Hammond-1550JBK.html
https://www.banzaimusic.com/Enclosure-XXL-Die-Cast-Aluminum.html
1550WJ | Botier IP66, en Fonte d'aluminium, Dimensions 275 x 175 x 63mm, srie 1550 W | Hammond
A+!
Yes, thanks !
Just for the fun, some pictures of the prototype built in 2008, while the finished amps were completed in July 2015 🙄 :
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
A+!
tubelectron, only one very picky comment, plastic speaker binding posts? The rest really looks great.
Really impressive, and very clever.
I like the use of the plastic base for the 300B amp. It actually looks great, and it's so much easier to work.
I like the use of the plastic base for the 300B amp. It actually looks great, and it's so much easier to work.