Harmony H 420 / Fully Serviced / 1960s / 115 Combo / Valco / (ffo Supro Thunderbolt)

As low as $41/month with
This seller is open to offers
Shipped From
Loud Art Gear Supply
Durham, NC, United States
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About This Listing

Harmony H420 in excellent electrical and playing condition, and fair to good cosmetic condition.

Fully serviced less than 5 hours of play ago by well respected pro tech Yontz Sucre, owner of Mad Science Works in Raleigh, NC. Receipts of work done included with purchase. 

Circuit is stock with all caps/out of spec parts replaced. Cabinet is original and has been stained and clear coated. Grill cloth and handle have been replaced. An extension speaker out has been added if you'd like to mess with other cabinet combinations.

2 6L6s and 2 12ax7s. About 30 watts from the factory. Marketed as a bass amp, and delivers wonderful tube tone on bass. Could be a bit quiet for live bass use depending on the set up, but would make a perfect studio companion.

But like most bass amps from the 1960s, it's even better on guitar. This one stays pretty clean with single coils up to about 7 on the volume knob and then fantastic overdrive starts to come into play. Breaks up a bit earlier with humbuckers. This amp loves being pushed! Boost, eq's, overdrives, and fuzzes play very well with this H420. 

Two band eq is unique and useful. I've found the full range of each knob, and all combinations to yield useful results. The treble and bass controls are deeply interactive, and together they influence the mids character a great deal. 

This is also a very simple amplifier. It's easily modified should you want it to overdrive earlier, or even coax a louder total volume out of it. I was interested in having it stock, but this guy could breathe a little more fire with some tweaks. 

This was made by the legendary folks at Valco and is very similar to the Supro Thunderbolt which they also made, but comes at a way smaller price tag. 

I've had the amp for about 4 years, but would like to put the cash towards a more robust home studio. 

Sold as is, with no returns. Will be packed well for shipping, and will ship with reverb insurance. 

Happy to send more detailed pictures and answer any questions.

This item is sold As-Described

This item is sold As-Described and cannot be returned unless it arrives in a condition different from how it was described or photographed. Items must be returned in original, as-shipped condition with all original packaging.

Product Specs

Listed3 months ago
ConditionGood (Used)
Good condition items function properly but may exhibit some wear and tear.learn more
Made In
  • United States

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