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Hi all. It's been awhile since I've posted as I've been busy with a move, renovations, etc...anyway...

I built my 5e3 a few years ago and it's serviced me well. A few months ago I started to get crackle/pop noises when playing at high volumes. I opened it up and poked around with a chopstick and couldn't find any loose connections. I also swapped out tubes with no difference. I haven't played it for a month or so and fired it up today. I tested it at high volume again with the same result and then the volume dropped out to maybe 10% of what it should be. The strange thing is that it seems to keep the same tonal characteristics. For example, plugged into the bright channel I can adjust the normal volume and get the breakup and clean just like always, just at a very low volume. Before I jump in I thought I'd throw it out there to see if other 5e3 owners might have experienced something similar. Thanks for any help.

-Duke

First start with the voltage measurements and post them. We can go from there. Did you also change your rectifier tube?

_________________
Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

Voltages

V1. 1-141.5
3-2.23
6-138

V2. 1-186.7
6-225
7-17.3
8-45.2

V3. 2-382
8-22.3

V4. 3-384
4-356
8-22.2

V5. 2-409
4-375
6-375
8-409

Filter caps measure as follows: 389, 356, 268

After checking voltages I plugged in and the volume was back to normal. But it still cuts out at high volume especially when attacking high notes. I changed all the tubes with no difference. I held a note and lower volumes and poked everything I could with no audible results. I cranked it very high and managed to get it to cut out to low volume for about three seconds and then the volume jumped back to normal. ????

Your plate voltage on V2 (pin 6) is low.

Did you mean to measure the voltage on pin 6 of V3?

Could be a bad plate resistor on V2, could also be a loose connection around there.

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http://pdfelectronics.com

See updates above.

Ya so your voltages are fine then.

Look for a bad solder joint/connection and/or loose wires.

_________________
http://pdfelectronics.com

Sounds like a good next step. It sounded like a power issue so you might start
with rectifier, plate or cathode resistor and ground connections
intermittent ones are so hard to find

_________________
Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

This morning and desoldered and resoldered virtually everything. I fired it up and after a couple loud notes it dropped to low volume again and stayed there. Think Deluxe tones at apartment level volumes. Again I stayed plugged in and poked around the signal path and all the joints, grounds, etc. It seems stuck on low output now. Does this sound like a bad OT possibility. When I lost one before it farted around a bit and then totally died. I'm not sure how to test the OT but am willing to try if I'm walked through it.

Normally when they go, its lights out, but that is a possibility, although remote. We have spare OTs in stock. What is the part number on your OT?

_________________
Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

The numbers on the tranny read:

108-M
HTS-9800
9960935

If you think it's worth a try pm with payment info, Stephen.

That is the latest design spec transformer. It's very rare for an OT to fail.

_________________
Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

That is the latest design spec transformer. It's very rare for an OT to fail.

_________________
Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

Yeah, I think I have one of the first of the new bunch. I do have a BBQ OT I can test with. If that's the issue I'll order a new one from you, if not I'll pull it apart, test all the resistors, clean it up, and do a rebuild. I need the practice anyway.

All good now. Thanks for the help diagnosing the OT, Stephen.

Update...valve two pin two was shorting out. Easy fix but it sounded exactly the same as when the OT went out last time. Glad that's all it was!

_________________
Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps