New 5e3 build, faint sound..

[01bcat]

I was checking the resistors, that is how I caught it, switch on 1 jack wasn't working.
I also tried grounding the tube pins, no help. Still distorted, volume jumps in one spot on the knobs. Sounds terrible.
What next? Could it be a bad OT?

[Phildaman]

It also sounds like an input jack could be wired wrong and or not grounded right.
Short lugs 2 and 7 of the first preamp tube right to ground with an alligator clip lead and see if that kills the noise.

Bruce,

I just completed a first-build 5E3 myself, which I believe is a little noisy. If I short lugs 2 and 7 of V1 to ground as you described, what specifically should I look for in my jack wiring, presuming that does stop the noise...

[01bcat]

Raspy tones.....

I completely rewired my heaters and it substantially reduced the hum.
But I have absolutely no clean headroom at all, and when it does break up, it sounds like a blown speaker. Very little volume until 2 then it is just raspy sounding. No good tones at all.
I rechecked the pot wiring, and the input wiring, and re-flowed the joints.
Does anyone have any ideas what it could be, or have you had similar problems?
Thanks.

[Bruce / Mission Amps]

Bruce,

I just completed a first-build 5E3 myself, which I believe is a little noisy. If I short lugs 2 and 7 of V1 to ground as you described, what specifically should I look for in my jack wiring, presuming that does stop the noise...

Is it one of my kits and if so did you download the 110 megabyte photo album builder guide work?
I'd review the input jack's lugs vs the 1M resistors and the middle switch lug to be sure they are correct.
With no 1/4" phone plug inserted into any of the jack, the two grids of the preamp tube are at very very low potential and should be very quiet unless the preamp tube is bad.

[Bruce / Mission Amps]

I completely rewired my heaters and it substantially reduced the hum.
But I have absolutely no clean headroom at all, and when it does break up, it sounds like a blown speaker. Very little volume until 2 then it is just raspy sounding. No good tones at all.
I rechecked the pot wiring, and the input wiring, and re-flowed the joints.
Does anyone have any ideas what it could be, or have you had similar problems?
Thanks.

I have to assume you've double checked all your wiring but triple check to see if you have the wires from lugs 7 and 8 going to the right resistors on the circuit board... they could be flipped around on the 12AX7 socket, the one closest to the speaker jacks.

[01bcat]

Hey Bruce,
I actually pulled the board yesterday, and re-checked everything under the board.
I cant find anything wrong with the circuit. Is there a way to check the caps and OT?
Thanks!

[01bcat]

Thanks for everyone's help, great board.
I found a bad capacitor.
It sounds incredible!
Now for that 18 watt...

[Chuck H]

It's kinda like when your car breaks down. You find the problem but the car still won't run!?! It's because some other non obvious thing is wrong in conjunction with the main issue. You eventually find it, get back on the road and rationalize that even though you don't know everything about mechanics, you knew enough (and had enough confidence in yourself and your work/understanding) to look for something other than your own failings.

Kudos

Chuck

[Phildaman]

Is it one of my kits and if so did you download the 110 megabyte photo album builder guide work?
I'd review the input jack's lugs vs the 1M resistors and the middle switch lug to be sure they are correct.
With no 1/4" phone plug inserted into any of the jack, the two grids of the preamp tube are at very very low potential and should be very quiet unless the preamp tube is bad.

Bruce,

It's actually not one of your kits. I think I have ground issues, and that is what is causing my noise problems. I get the most noise when I use channel 1, so I thought you V1 grid test might help determine if I was correct (about grounding issues). My lead dress is less than stellar, and that may be part of the problem. With enough exploration, I'll find my problem. Except for the noise, the amp sounds great.

[vjf]

For those of you lurking here in preparation for a 5E3 build...buy your kit from Bruce! I can't think of any reason not to.

His parts are top quality, his technical support and customer service is exceptional.

I know this because I bought his kit. It was my first build and it worked the first time I flipped the switch.

[01bcat]

VJF,
While I have no problem with your statement, my kit was fine too. I do believe having a manual would have helped, though.
I would still be waiting for my kit instead of playing my new amp - if I ordered from Mission. I called them 1st, I think it was a 3 week wait, same with Weber. Fair enough...
Anyone could have sent me a bad part. I will also say that all the companies were responsive to my initial email.
Bruce is way more visible here, and I think that is fantastic.
The support at Triode was great, and the pricing was fair as well.
Funny thing is, I think I learned much more because I had an issue.
Really not sure about where I will get my next kit, but the "lag" time will matter once again. I am actually considering using multiple suppliers, and going scratch.
Cheers

[Chuck H]

I am actually considering using multiple suppliers, and going scratch.

If you plan to clone again I say go with a kit. Someone else has already sourced all the right parts and probably spec'd correct trannies that you either can't find or will cost twice as much as individual units. And think of all the shipping charges if you buy your faceplate from Mojo, trannies from AES, speaker from Parts Express, components from Mouser etc. You won't find everything you want in one place without some compromises. If you plan to build a design of your own then it's the only way to go though. Either way you'll spend easily twice what you would on a kit and no tech support (well, other than here )

Chuck

[01bcat]

True that Chuck.. But I want to at least give it a shot. Although it is nice knowing you are getting all the right parts, I think a scratch build may be a good challenge.

I may go back to kits, but I am really interested in the building, not "just" the amp. I think I have the Bug...

I also think it will prove itself out when I do the pricing, and crunch the numbers (sounds like you may have already)?
Cheers..

[Chuck H]

True that Chuck.. But I want to at least give it a shot. Although it is nice knowing you are getting all the right parts, I think a scratch build may be a good challenge.

I may go back to kits, but I am really interested in the building, not "just" the amp. I think I have the Bug...

Welcome, brother

I also think it will prove itself out when I do the pricing, and crunch the numbers (sounds like you may have already)?
Cheers..

True that. I build original designs. Recently for a big cootie in the biz. So far the pay is lousy The amps sound great but in this economy there's not as much room for hand wired amps and "boutique" designs as there was five years ago. I've been shelved in favor of a Chinese factory model Great experience though. I still do consulting and actually counceled in favor of the budget product to remain honest.

But I am speaking (writing) from experience when I speak about prototyping costs. What you propose should be similar. Very rewarding though, if your pockets can take it.

Chuck

[01bcat]

Hmmm.... Chinese made factory model? I will take a stab that it is an EL84 amp..
I would be afraid to do original designs until I sold quite a few "borrowed" ones, based on amps people know and possibly always wanted, but can't get now - for a reasonable price anyway. It seems like that is the best way to get started. If you punch the chassis (what is the plural of chassis?) yourself, and make the cabs, you could possibly make a few bucks per unit?
Do you have a brand name for your amps (pm me if you feel it is more appropriate)?
Now if I could just figure out how to make those transformers.....