Tube tester!

[KuruPrionz]

I know, archaic...

I had the opportunity to purchase a working Hickok 600a tube tester in decent condition for $100. The seller included a complete printout of tube charts since the roller chart in the unit is broken and a PITA when it does work - too slow.

Also included is the manual for calibration of the unit.

 

I've got a stash of tubes that need testing. Some will stay and some will go. I still own 2 small all tube guitar amps ("clones" of vintage designs), a tube microphone (12ax7) - CAD M9 and recently a Blue Robbie tube mic pre.

 

Not my favorite thing but long overdue and some of my stash is pretty valuable if the tubes test well (some Amperex Bugle Boy from Holland for one). Ugh, onward and upwards!!!!

[Mike Rivers]

I know, archaic...

I had the opportunity to purchase a working Hickok 600a tube tester in decent condition for $100.

 

It wasn't too long ago - or maybe it was too long ago since I seem to be forgetting what year this is - that these things were hard to give away. I don't know my tube tester models, but most test the same things, and there are some things with guitar amplifier tubes that people want or need to test that aren't tested by most models.

 

I suspect that by now you've read a few books about guitar amplifier maintenance. I don't know of any standard service shop tube testers, for example, that test for noise, either electronic or mechanical (microphonics). They all test for emission, most of them test mutual conductance or AC gain, but that might be as far as they go. I know that people build test fixtures for matching tubes, and probably for noise, too.

 

I, too, have a carton of tubes but never got around to getting a tube tester. I figure that whatever needs the new tube is my tube tester.

[KuruPrionz]

I know, archaic...

I had the opportunity to purchase a working Hickok 600a tube tester in decent condition for $100.

 

It wasn't too long ago - or maybe it was too long ago since I seem to be forgetting what year this is - that these things were hard to give away. I don't know my tube tester models, but most test the same things, and there are some things with guitar amplifier tubes that people want or need to test that aren't tested by most models.

 

I suspect that by now you've read a few books about guitar amplifier maintenance. I don't know of any standard service shop tube testers, for example, that test for noise, either electronic or mechanical (microphonics). They all test for emission, most of them test mutual conductance or AC gain, but that might be as far as they go. I know that people build test fixtures for matching tubes, and probably for noise, too.

 

I, too, have a carton of tubes but never got around to getting a tube tester. I figure that whatever needs the new tube is my tube tester.

 

I had a Hickok 600a quite some time ago. It can be a tedious process. I am not sure I understand the cryptic instructions regarding mutual conductance. Testing a pair of Baldwin labelled 6L6 and depending on how I am understanding the scale the first tube of the pair is testing pretty low. I may have to compare it to known good tubes and see if they show similar results.

I remember this pair sounding very good in my Redplate Blues Machine and Allen Accomplice - both amps that require you to measure and adjust to properly bias the tubes in the amp.

 

And both amps needed to be re-biased every now and again. Fine, until the Redplate went badly out of bias on New Years Eve. That was my last gig with a tube amp, a nightmare of toneless struggling.

 

I didn't have a tester when I owned those amps, I just popped them in there, biased them and went with it. I put newer Russian tubes in when I sold them and kept the vintage ones. Not sure who made the Baldwins, I also have a pair of Conn labelled that are Sylvania 6L6, a sought after tube. I should compare them.

 

My current amps only use 6V6 or EL84 / 6BQ5. I never gig with them, too many tube failures at gigs, I will not repeat that less than delightful experience. Solid state has gotten pretty amazing, I'm pretty sure a considerable aspect of the "tube sound" is emotion/nostalgia.

 

I wish Peavey would make a Mic/Instrument channel strip with Transtube in it. They used to but the latest version of TT is hugely better than even the legendary Red Stripe series. Transtube is probably Hartley Peavey's greatest contribution to the world.

[KuruPrionz]

Lots of tests!!! You could spend an hour testing one tube. Ugh...

 

The seller was working his way up to a new computerized tube tester that costs over $5k new.

You plug in a tube, let it warm up and hit the Go button. Then it knows everything and displays all information, done deal.

 

Glad I don't have that many tubes!!!!!!

[Dr Mike Metlay]

I would imagine Metasonix needs absolutely top quality tube testers for its products.

 

(Actually Metasonix f#Çk!ng RULES.)

[KuruPrionz]

I would imagine Metasonix needs absolutely top quality tube testers for its products.

 

(Actually Metasonix f#Çk!ng RULES.)

 

Yes, and Manley and Tube Tech just to name a couple more manufacturers that use select high fidelity tubes.

 

Aspen Pittman brought matched tubes to the common man - Groove Tubes have improved the tones of many guitar amps. They would have to own some fantastic, efficient tube testers to stay in business, too labor intensive using a dinosaur tube tester like my Hickok.

 

Randall Smith - founder and owner of Mesa Engineering - Mesa Boogie amps, had a concept long ago that he would eliminate the bias adjustment on his amps and sell only tubes that were within a somewhat narrow testing range.

They've had a rigorous tube testing procedure for many decades. Mesa tubes may not be the very highest fidelity but they've been very reliable in my experience. Guitar amps are gloriously low-fi by nature, it would be painful if you could hear all the high frequencies clearly.

 

This is an interesting 5 minutes!

[Doerfler]

for those who prefer embedded videos

 

[video:youtube]

[KuruPrionz]

Thanks Dave, me not smart!