Finished 😀
The top plate gets nice and toasty like Pete mentioned, but so does the mains transformer 😉
I hope the mosfets can handle it.
All in all I am very happy it sounds great!
Thank you Pete for another great amp. (note: Millett hybrid on pre-amp duty)
An externally hosted image should be here but it was not working when we last tested it.
The top plate gets nice and toasty like Pete mentioned, but so does the mains transformer 😉
I hope the mosfets can handle it.
All in all I am very happy it sounds great!
Thank you Pete for another great amp. (note: Millett hybrid on pre-amp duty)
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That's beautiful! I hope mine turns out as nice as yours. I think I'm going with a black anodized top plate, however. FrontPanelExpress, here I come!!!!
-D
Got mine (mostly) built up as well.
Assembled DCPP Amp (2 x 36W) on Flickr - Photo Sharing!
I'll try and get some hi-res photos up soon.
I'm running Heathkit AA-100 iron with pretty good success, B+ a bit higher, and getting ~36 WPC. The power xfmr is getting pretty dang hot, creeps up to 125...135...145 F over the course of a few hours of listening. I haven't let it get much hotter but it didn't appear to reach any steady state yet.
I've read other posts on stock AA-100 transformers running at 125 F being normal. For you guys that have done the stock build, what temps are you seeing out of the Edcors?
Thinking about putting some heatsinks right on top of the transformer, or maybe a fan.
Assembled DCPP Amp (2 x 36W) on Flickr - Photo Sharing!
I'll try and get some hi-res photos up soon.
I'm running Heathkit AA-100 iron with pretty good success, B+ a bit higher, and getting ~36 WPC. The power xfmr is getting pretty dang hot, creeps up to 125...135...145 F over the course of a few hours of listening. I haven't let it get much hotter but it didn't appear to reach any steady state yet.
I've read other posts on stock AA-100 transformers running at 125 F being normal. For you guys that have done the stock build, what temps are you seeing out of the Edcors?
Thinking about putting some heatsinks right on top of the transformer, or maybe a fan.
hey Geek,
How'd you like to look through a Peerless S-226-Q output? Nominal 20W, 6k6 a-a, 20-20 Plus series? maybe its 20-20 brother the S-230-Q for comparison? Loved your write-up on the Dynaco Iron, thanks.
cheers,
Douglas
The Edcor mains transformer can still be touched without getting burnt as can the top plate surrounding the Mosfets.
The pentodes can also be safely touched.
Nevertheless the sweep tubes WILL BURN YOU!!
Lets face it this is a DIY project that in its standard form would never pass any kind of safety standard. Commercial tube amps seem to have cages surrounding anything HOT.
The Edcor mains transformer can still be touched without getting burnt as can the top plate surrounding the Mosfets.
The pentodes can also be safely touched.
Nevertheless the sweep tubes WILL BURN YOU!!
Lets face it this is a DIY project that in its standard form would never pass any kind of safety standard. Commercial tube amps seem to have cages surrounding anything HOT.
Do you have any tube gear that won't burn you? Everything I have is home-built and has exposed tubes. At least the B+ is safely buried in the chassis.
I have just trained my kids to stay away from the tubes as they know they are hot.
-D
Still trying to teach my 10 month old baby girl to stay away from cables and the such.
No fear the DCPP is way out of reach!
Thanks! 🙂
Sure! If you can pull the core, you'd save a bundle in shipping. PM me for details.
Cheers!
Just got my shipping notification from Edcor - I should have my PT on 12/22, which means I can start breadboarding right after Christmas. Woo!
-D
-D
You mention higher B+ with the Heath AA-100 power transformer...what B+ and output tube idle currents are you using? I'm curious because I may also want to build using the AA-100 iron. The originally specified circuit values shouldn't load the Heath transformer beyond what it supports in the AA-100 design (the 6.3V filament load is a bit higher here, but having no 5.0V filament load should more than compensate). Thanks!
So - for those of you that have completed the amp, can we have a quick review of the results?
-D
-D
In my view an amp like this is never really "completed". It gets listened to until I grow tired or bored with it and then it gets experimented on some more. I haven't been home, so it is still in the same condition that it was in for my last post (#168 and #170). Of course 125 WPC is no small feat, but I plan to dial it up a bit more before I decide on the final configuration and build a real power supply and a box for it. In its current form it is an excellent sounding amp, but it is an "engineers amp" and the engineer in me wants to tinker with it some more.
I ran mine for a day or two with 6JN6. Within its limits, it's a fine amp. Pushed hard, it did not do as well as the RLD amp, but that's asking more of the amp than it is designed to give.
To solve that problem, I switched the output tubes to 6LF6 and ran it off a 600V bench supply with a 1250 ohm output transformer. I haven't had a chance to do bench measurements yet, but I did manage to crack a load resistor during testing, so I'm certain that the power is over 100W.
One request: my amp is lashed together on a piece of plywood. Has anyone gotten a top plate from Front Panel Express, and if so, could I get a copy of the file? I don't have AutoCAD anymore, so can't open Pete's dimensioned drawing.
To solve that problem, I switched the output tubes to 6LF6 and ran it off a 600V bench supply with a 1250 ohm output transformer. I haven't had a chance to do bench measurements yet, but I did manage to crack a load resistor during testing, so I'm certain that the power is over 100W.
One request: my amp is lashed together on a piece of plywood. Has anyone gotten a top plate from Front Panel Express, and if so, could I get a copy of the file? I don't have AutoCAD anymore, so can't open Pete's dimensioned drawing.
Unfortunately, the way providers (I use GoDaddy.com) can offer "unlimited badwidth" (really "unlimited traffic") is to restrict the data transfer rate to each domain hosted on a server. The result is that if there is a lot of activity the response gets slower and slower.
Once some guy posted a link to a PDF on my site on EDN. It slowed things down so much that I could not even access the server. Eventually I had to get the sys admin to delete the file so I could get back in.
I notice whenever I post a new PDF book, or even just post something new in the forums, my site slows down.
Being a self-supported hobby, I can't afford a dedicated server with a fat pipe to the Internet... and I have no desire to become expert enough to roll my own server.
Pete
I have figured this out too. I learned not to post too much new stuff at once.
That isn't too hard these days. There are several Linux geeks here that would do it for a few beers. I am sure that is true at the place you work. The hard part is affording the "fat pipe to the Internet". DSL or cable internet is usually quite assymetric. The down load speed is far faster than the upload speed.