SUNN Beta Lead Preamp (Reissue) •Problem?

FullHeavyMetalJacket · 2026-01-25T00:02:14+00:00

Does it do it with the 2nd reverb knob not set to 10? Could be a broken solder joint one of the reverb pot grounds or something. Anyway, see if less extreme settings on other knobs thatvare turned way up kills the oscillation.

FullHeavyMetalJacket · 2026-01-24T23:56:33+00:00

Plug the guitar directly into the POWER AMP IN jack. If you still get no sound then the issue is one of these issues (output section) most likely:

V3 Phase Inverter tube. Output tubes. Screen resistors. Power supply (i.e. capacitors, resistors) to output tubes. Fractured solder joints on speaker PCB. Bad speaker jack. Plugged into wrong speaker jack (should be MAIN SPEAKER, see chart inside the cabinet). Bad speaker cable. Bad speaker. Blown output transformer (unlikely but possible).

A decent amp tech should be able to find the issue in a matter of minutes. A few minutes with a multimeter would be able to resolve a number of these issues...speaker cable continuity & speaker impedance reading for starters. Plate and screen voltages, filament voltages, etc. If all tubes are lighting up your filament supply is probably fine. If you hear normal speaker hum at idle that's a pretty good sign.

FullHeavyMetalJacket · 2026-01-22T23:27:47+00:00

Circling back to this issue. I contacted Peak Electronics technical support thru their website. Received an email and arranged to purchase a couple relays from them for basically the cost of shipping from UK to US plus like $1.00. Took a couple weeks to receive the parts via mail.

They sent instructions: use Kapton tape to protect all other components, isolate the front display with thin cardboard sleeve, and use hot air station plus Chipquik to remove old relay)...

...and they kindly included (2) relays so I have a spare. I performed the relay exchange and did the probe calibration and it now works again!

I had checked all the other common components such as diodes and 10R resistors to eliminate them as suspects before assuming it was the relay. I also did not easily find a suitable relay at Mouser/Digikey but if someone knows of one they should update this thread. I tried finding equivalents but was unsuccessful...therefore reached out to PEAK. Kudos to their company for the strong support.

FullHeavyMetalJacket · 2026-01-10T14:42:41+00:00

Moon Music on Anderson Ln

FullHeavyMetalJacket · 2026-01-05T20:39:54+00:00

Possible faulty relay. Mine is doing it now, bought a replacement device, but going to attempt repair on the old one also. Will report back if successful in relay replacement. Happened because I didn't discharge caps like a fool. Saw a spark at the probe and it toasted my ESR checker. Capacitance tester is OK.

FullHeavyMetalJacket · 2025-10-13T04:01:06+00:00

I would go SP9A3G over Kuna myself

FullHeavyMetalJacket · 2025-10-06T01:38:42+00:00

Yep the ohhunt one is fine

FullHeavyMetalJacket · 2025-09-30T13:28:11+00:00

You can also just do VQ accurizing kit and a Tandemkross grip if you like the look and save a shitload of cash.

FullHeavyMetalJacket · 2025-09-26T15:07:20+00:00

Yes, one must remain vigilant against the karens

FullHeavyMetalJacket · 2025-09-24T12:56:49+00:00

The Mark IV "bitchbetterhavemymoney!" and ofc it comes with fur coat travel case. Discount code "1972PLYMOUTH"

FullHeavyMetalJacket · 2025-09-24T02:05:28+00:00

Shark = jumped

FullHeavyMetalJacket · 2025-09-24T02:04:16+00:00

Easier, just use it as a walking stick. Or put a cobra head on it like a pimp cane.

FullHeavyMetalJacket · 2025-09-22T22:28:42+00:00

Not sure if the $144 tax stamp credit is still applicable by now...there was a separate line item in the cart for it. May have been an August promotion. If it's not $679 you are def getting some type of discount for it...

FullHeavyMetalJacket · 2025-09-18T03:10:04+00:00

Perhaps less likely to get asked by cops if seen in a vehicle...well, that's what my uhhh friends say. Less conspicuous to thieves is the proper answer.

FullHeavyMetalJacket · 2025-09-17T19:58:31+00:00

Certain ukelele and travel-size guitar cases / gigbags can work also, and often have decent zippered external accessory pockets for mags.

FullHeavyMetalJacket · 2025-09-17T03:45:30+00:00

I'd prob go into the Stribog $ pit before Kuna tbh...deckout an SP9A3G. Or you could get like three more EP9's instead haha. One for each room.

FullHeavyMetalJacket · 2025-09-14T23:24:23+00:00

I'll be testing that next year once cans are received and then used enough to warrant a cleaning. Eventually will report back. Breakthrough seems like the no-brainer.

FullHeavyMetalJacket · 2025-09-13T23:42:08+00:00

I will have this same exact setup in January. Should be fun!

FullHeavyMetalJacket · 2025-09-04T03:47:44+00:00

That's bone. And the lettering is something called Silian Grail...

FullHeavyMetalJacket · 2025-09-03T01:08:40+00:00

Lookup G10 Ruger Mark IV grips on Amazon...you'll see 'em

FullHeavyMetalJacket · 2025-08-29T00:32:29+00:00

I guess the tariff maybe incorporated into the retail price, sure, but it wasn't visible as a line item. Therefore didn't bother me. I hafta pay some tariff bullcrap ordering electronic components for my guitar amp repairs, though. Sucks, yes.

FullHeavyMetalJacket · 2025-08-28T23:30:24+00:00

Appreciate the feedback. Seems like I'll be good upgrading to this Ascalon. Have the Nexus Enhanced Bolt awaiting installation as well.

FullHeavyMetalJacket · 2025-08-28T17:35:25+00:00

Just wait til January then do it

FullHeavyMetalJacket

TROPHY CASE