Hey guys, just wanted to share my new build, and also say THANKS! If it weren't for the search function on this site and the folks here who actually know what they're doing this amp never would have happened.
It's based on the 16x8 layout in a Princeton chassis. I added a rectifier tube just because I like them and polished a few component values here and there like you do. It's nothing super special, but I think it came out pretty good for my first blank chassis build.
I think it took just as long to figure out where to punch the holes as it did to assemble the thing.
My goal was a compact, every day carry stage amp that gives good rock'n'roll without getting me cussed out by the sound guy. I think I got there. I have nicknamed it the Rumble.
6v6's over a 5y3, Edcore trannys and a fairly beefy choke. I'm confident I could run 6l6's or EL34's over a GZ34 in it and not hurt anything, but I haven't tried it yet. Just kinda getting to know it for now.
New D'lite build
Moderators: pompeiisneaks, Colossal
New D'lite build
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Re: New D'lite build
Ok, so now is the part where I ask a question. I've got a good number of hours and some jam sessions on this thing, and overall it's pretty hip. There is one really unusual quirk to it though. When first firing the amp up from standby, on the first start of the day, it sounds just a bit fizzy for the first five minutes or so until everything gets up to temperature and then it smooths out and sounds surprisingly good for something I built myself. Neither I nor any of my guitar geek friends have encountered this before. It's not really a problem, but it is quite curious.
I have tried different tubes. Makes no difference.
Letting the amp sit on standby makes no difference, it has to be played until it clears up.
The fizz is sort of reminiscent of a slight impedance mismatch. It reminds me of messing around with universal output transformers that would get really close, but not quite right.
These parts are all new, including the speaker, which may be part of it.
One of the things I did a bit differently on this build is use a 200ma 5H choke in place of the 500 ohm choke resistor. I may reverse the choke leads to see if this makes a difference.
Have any of you ever encountered something like this? This sort of rough running from a cold start is something I'm accustomed to dealing with in hot rod cars, but I have never encountered it in an amplifier before. It doesn't seem like anything is really wrong, but it's got me curious enough to throw it out here and see what you guys think.
Running a pair of 6v6's over a 5y3 with an 8ohm speaker.
I have tried different tubes. Makes no difference.
Letting the amp sit on standby makes no difference, it has to be played until it clears up.
The fizz is sort of reminiscent of a slight impedance mismatch. It reminds me of messing around with universal output transformers that would get really close, but not quite right.
These parts are all new, including the speaker, which may be part of it.
One of the things I did a bit differently on this build is use a 200ma 5H choke in place of the 500 ohm choke resistor. I may reverse the choke leads to see if this makes a difference.
Have any of you ever encountered something like this? This sort of rough running from a cold start is something I'm accustomed to dealing with in hot rod cars, but I have never encountered it in an amplifier before. It doesn't seem like anything is really wrong, but it's got me curious enough to throw it out here and see what you guys think.
Running a pair of 6v6's over a 5y3 with an 8ohm speaker.
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Re: New D'lite build
Doesn’t sound reminiscent to me. But might be that your warming output tubes start to draw a bit more current as they warm up, thus slightly shifting the bias point? Maybe the PI tube getting more balanced because of the same reason.
Point is, I observed that bias shift in my own amps, but can’t remember if it took 5 minutes tonreally settle. Something you can easily check with your DMM though. Measure your voltages right after power on and after 5 minutes and compare.
By the way: this looks as a fun build. I really like the out of the usual box method with a different chassis, tube recto, etc.
Point is, I observed that bias shift in my own amps, but can’t remember if it took 5 minutes tonreally settle. Something you can easily check with your DMM though. Measure your voltages right after power on and after 5 minutes and compare.
By the way: this looks as a fun build. I really like the out of the usual box method with a different chassis, tube recto, etc.
Re: New D'lite build
By the way: can’t see the 5y3 you are using. I tried a few of those recently and ended up with a JJ, because that was the only one remotely behaving as a real 5y3. The rest of the modern ones: not the required voltage drop and behaving more like a small gz34. What do you use?
Re: New D'lite build
Hmmm... Bias shift is an interesting thought. I'll plug in my leads and see if there's a change when it smooths out.
I've rolled a variety of rectifier tubes through this thing. JJ, JAN Phillips, Amperex, an interesting Russian 5Z4. None seem to have any effect on the warm up period, but they all change the character of the amp drastically. This thing is super sensitive to tube selection for whatever reason. I'm currently running an Amperex because it sounds the best to my ears. Not as firm as a JJ, not as saggy as a JAN. I have noted that the Amperex's (I have a few of them) trend towards a bit higher voltage than the others, but not enough to burn anything down.
This thing is not as smooth and sweet as a proper D-style amp. It's a bit edgier or "more throaty". Has a bit of a rougher edge to the overdrive that I actually really like. Run it up into tight compression and you can play metal with this thing. It's fun and handy, with good volume flexibility which were my primary goals. Assembled from components that are readily available for purchase so if something happens to it, it's not the end of the world.
I have another blank chassis, and I'm considering another one of these with a 35w 6.6K primary OT offered by Edcore that was spec'd by RJ. I think that might open it up a bit. But that's something for future me to worry about.
I've rolled a variety of rectifier tubes through this thing. JJ, JAN Phillips, Amperex, an interesting Russian 5Z4. None seem to have any effect on the warm up period, but they all change the character of the amp drastically. This thing is super sensitive to tube selection for whatever reason. I'm currently running an Amperex because it sounds the best to my ears. Not as firm as a JJ, not as saggy as a JAN. I have noted that the Amperex's (I have a few of them) trend towards a bit higher voltage than the others, but not enough to burn anything down.
This thing is not as smooth and sweet as a proper D-style amp. It's a bit edgier or "more throaty". Has a bit of a rougher edge to the overdrive that I actually really like. Run it up into tight compression and you can play metal with this thing. It's fun and handy, with good volume flexibility which were my primary goals. Assembled from components that are readily available for purchase so if something happens to it, it's not the end of the world.
I have another blank chassis, and I'm considering another one of these with a 35w 6.6K primary OT offered by Edcore that was spec'd by RJ. I think that might open it up a bit. But that's something for future me to worry about.
Re: New D'lite build
So, I tested for bias shift and didn't really see much. The amp starts to smooth out after about five minutes, and may continue to improve a touch for a further few minutes after. At that point it may just be a matter of wanting to hear something rather than an actual change though. It took about ten minutes of playing to notice the tiniest tick in the bias voltage, from a steady .023 to an occasional tick up to .024. Not enough of a fluctuation that I would expect it to make a difference.
An interesting test to run though. Thank you for the suggestion. I'm pretty much operating at the edge of my knowledge and ability here, so I appreciate the input of those more experienced than myself.
An interesting test to run though. Thank you for the suggestion. I'm pretty much operating at the edge of my knowledge and ability here, so I appreciate the input of those more experienced than myself.