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The JE Labs/ Angela SE 2A3 amp done my way

WOW, looks great Nate!

Get me some specs for your box and I'll get to work on it. Or maybe I'll have to stop by for a look see.

Can't wait to hear it.

OUTSTANDING!
 
Thanks Gary! I'll see what I can do to get some good measurements for you. We'll have to get RC over here for a listen too.
 
Congrats on a beautiful job. I'm anxious to hear your listening impressions, once you get the Klipsch's hooked up. :thmbsp:
 
Well, the word is good! My Forte's are supposedly 98 dB sensitive. I put the amp in, and after giving it a chance to warm up a little I was able to make it DEAD quiet! Those little hum pots are pretty slick - about all the gadgetry I need. Pressing my ear to the grillecloth revealed nothing on the left channel, and only the slightest of residual hum on the right. From a foot away, you won't hear it.

I haven't had a chance to turn this up since no one else is awake yet, but I can tell that the middle and upper registers are really nice. For some reason I'm hearing less bass now than I had with the SE EL84 Olson. Maybe I need more volume, maybe different drivers. Right now I've got old RCA 6SL7's in the front end. Anyone have ideas about that?
 
Nice job Nate and congrats on it coming up right the first time out!

Looking forward to hearing your thoughts as you do some listening and tweaking. As much as I love the 45, the 2A3 is where I live now as it's got a little more power and does most things a little better than the 300B amps I have.
 
The amp is looking great Nate! You did a real professional job laying everything out and the solder work looks top notch. I really look forward to hearing it.

RC
 
WOW :drool:

I lust for your amp; it looks great - very clean wiring job !

It would look really sweet with a teak base :yes:
 
Thanks fellas!
Billfort said:
As much as I love the 45, the 2A3 is where I live now as it's got a little more power and does most things a little better than the 300B amps I have.
Click to expand...
Bill, shouldn't I be getting some decent bass extension here? It's like someone turned a tone control all the way down.
 
I haven't heard any problem with the bass using a 2A3, actually, within it's power limits, the 2A3 amp I use outperforms my 300B amps in the bass. Some friends and I have even done direct comparisons between my 2A3 amp and some decent SS amps and we where surprised how well the 2A3 hung in there bass wise, it even bettered one of SS amps we tried.

I am talking about a different amp and speaker combination of course but I don't think it is something you could blame on 2A3 per-se.
 
That's what I thought... I'm looking for other explanations for this. Could be the driver tubes, maybe the OPT's... who knows? I'm hoping Pak will weigh in, as he's actually built this one before. I have yet to try the 6EM7's he recommended, so maybe that will help. Of course, some more listening time is in order.
 
Well, poo.

I blew a fuse. :no:

It's a slo-blo, 2A as the circuit calls for. Where do I start looking?
 
Wow, nice job. Your layout and wiring are spot on. Next time someone ask how they should lay out there amp I’ll say just look at what Nate did. I like the way you put the 40uf caps up front. Mine are always at the back of sides, why? Because that’s how I’ve always done it. learn something new every day.

One thing the cathode resistors run a bit warm. When you are ready to button it up, pull the black caps away from them as much as the leads allow.

The bass may come with break in also you can experiment with the different taps on your output transformer. Then there’s tube rolling. Do you want a pair of NOS Russian 6SL7’s

Drop me a PM with your address…John
 
Hey, thanks for the kind words, John. I'm feeling pretty good about how this turned out and it's nice to hear others say so, too. :thmbsp:

I'm not sure how the 40uf caps ended up where they are, but it was a nice fit. Call it beginner's luck? You can take credit for the grounding scheme! :D

The caps over the cathode resistors float nearly a half inch above them. I plan to put lots of ventilation underneath, too.

I think I fixed my fuse popping situation. When the second one went, I noticed that the rectifier (old, used) gave a nice flash before the lights went dark. I put in a different tube and it's been behaving nicely for the last hour.

My OPTs have 2.5K and 3.5K taps, currently wired 2.5K. I don't know enough to predict what 3.5K will do for me. Anyone want to give me a hint?

I'm an impatient man. I've already rolled in some 6EM7's to see what difference they make. Problem is, I hadn't listened to the 6SL7's I had in there enough. I think the 6EM7's sound better...
 
Fuses blow, try another if they keep blowing look for something that got too hot. Start with the power supply resistors. Recheck that all of the electrolytic caps are wired correctly, it is not beyond reason to get a leaky one. If you don’t see anything wrong, run it with the light bulb and see who that works. Use the biggest bulb you have on hand.

As to the bass. You should get decent bass, I don’t know what el84 your running but they should be in the same park. If not the two problems may be related. Post your voltage measurements and how you have your OP trans connected…John
 
I'll give you an honest account of my experiences with the tubes you are using. The RCA 6SL7s are my least favorite in that spot (driving EL34s in triode mode). I found them to be very lacking in the bass dept. The very best (all around) 6SL7 I've found is the Sylvania with bottom getters. The deepest and most bass I've found in a 6SL7 is the GE with silver colored (some say it's nickel) round plates. As far the Sovteks, they should make bass ok, but I find them to be just a little "edgy" towards the top, compared to a good ol' RCA dual plate. I think your on the right track with your suspicions of the driver tube. Jay
 
I knew you could do it....:D I't always a plus when planning an patience pays off..Well done my friend..:thmbsp:

Dave
 
Music is playing right now. It's very detailed. Vocals are crisp, clean. I'm wondering if "bright" might be the word I'm gravitating to... I'm not sure yet. But it's an altogether different sound than my beloved little Olson, and I think I like it. I swapped in some Sylvania 6EM7 drivers and the bass seems to be coming in better.
 
Redboy said:
Hey, thanks for the kind words, John. I'm feeling pretty good about how this turned out and it's nice to hear others say so, too. :thmbsp:

I'm not sure how the 40uf caps ended up where they are, but it was a nice fit. Call it beginner's luck? You can take credit for the grounding scheme! :D

The caps over the cathode resistors float nearly a half inch above them. I plan to put lots of ventilation underneath, too.

I think I fixed my fuse popping situation. When the second one went, I noticed that the rectifier (old, used) gave a nice flash before the lights went dark. I put in a different tube and it's been behaving nicely for the last hour.

My OPTs have 2.5K and 3.5K taps, currently wired 2.5K. I don't know enough to predict what 3.5K will do for me. Anyone want to give me a hint?

I'm an impatient man. I've already rolled in some 6EM7's to see what difference they make. Problem is, I hadn't listened to the 6SL7's I had in there enough. I think the 6EM7's sound better...
Click to expand...


Never hurts to try the 3.5K tap. If you don't like it, swap back. It may give more damping, maybe not...

I don't understand....I thought a 6EM7 is a dissimilar triode like a 6EA7. And you've swapped the dual triode 6SL7 for a dissimilar triode?

Maybe I better read through this thread a bit more......
 
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