Mook's Taste Tests for 6V6


Well, here are the 6V6 Taste Test results. I tested 10 different sets of 6V6s in a Fender Tweed Deluxe and Fender Blackface Deluxe Reverb. Test results are not too surprising. Vacuum Tube Valley did the same in their issue #10, Summer/Fall of 1998 (believe it or not, I did not get the idea of doing listening tests from VTV). In some respects, my findings are the same as theirs. In other, respects, we differ. So, this report will serve as a "second" opinion for 6V6 tubes in guitar amps.

The following list of gear is for "comparative" purposes only. This is NOT meant to plug or praise certain manufacturers. The guitars were plugged straight into the amps with a 10-foot Spectraflex cord. Volume and Tone knobs on the guitars were set to full (10).

One thing to note about the pickups in these guitars: It seems to me that the Texas specials are just as "hot" if not a bit hotter than the Seth Lovers. The Seth Lovers are actually fairly low output and have lots of high end. Also, note that the Tweed is equipped with a P12R. Some of the "mush" (when the tubes were distorted) surveyed in the Raw Data section, is probably attributed to this fact. Both guitars were strung with D'Aquisto nickel round wound size .012-.052.

Tubes tested were Russian GT, Chinese GTB-C, Groove Tubes HD (the "cheap" 6L6), GE JAN (with thin black wafer base), Brimar British GT, PhilipsECG GT JAN, Mazda GT (France 1952), Visseaux GT (France 1951 Military with metal base), Marconi/MWT GT/G, and RCA GT (Black Plate). This list pretty much represents the "worst" to the "best" in terms of the 6V6-type tube.

I played both guitars through each amp for every duet of 6V6s. Both amps were evaluated with the volume knob on 3.5 (clean) and 10 (distorted - or 12 in the case of the Tweed Deluxe). I played for about 10 minutes on each 6V6 duet. Hot tubes were removed with leather gloves. In the case of the Blackface, I kept my BiasProbe attached to one of the tube sockets and every time I inserted a new pair of tubes, I adjusted the bias to 20mA.


Russian GT:

Tweed - With the LP, all pickup selections sounded fairly nice. Although there was no special magic or harmonic richness, these tubes were balanced. When distorted, the bass held up nicely. With a Strat, again, they were good clean, but when distorted, they had a mushy bass and piercing top end.

Blackface - Sort of brittle when played clean using the LP. Not bad when played distorted, but a bit "ratty". These tubes were nicer sounding with the Strat. They were a bit brittle in some pickup positions, but the clean and distorted tones were fairly nice.

Chinese GTB-C:

Tweed - With the LP, these sounded OK when clean. Very two-dimensional - nothing special. When distorted they sounded incredibly "ratty", more so than the GEs. These tubes liked to distort early. Even though they didn't evaluate too well with the LP, they actually sounded good with the Strat. Actually, I preferred these over the GEs for the Strat. When distorted, the bottom end was "mushy", but they gave a decent "Clapton" tone. The Strat second position was best.

Blackface - These tubes were piercing with the LP. When clean, the bass response was almost non-existent, especially on the neck pickup. Even though they didn't sound too good when played clean with the LP, surprisingly, they weren't too bad when played distorted. With the Strat, I was pleasantly surprised - I got some nice clean chime. But, even though they weren't too bad clean, they sucked when distorted.

Groove Tubes HD:

Tweed - With the LP, these tubes were lifeless and had no harmonic overtones. But, as lifeless as they were, they has a basic "good" clean; they were not piercing at all. Decent "jazzy" clean sound in all positions. When distorted, they were just...decent. They weren't "farty", but there was no magic. With the Strat, these tubes did better. Fairly decent mids and highs are not piercing. Nice in position 2 when clean. When distorted, they actually sounded pretty good - fairly smooth. Again, nothing magical, but they had a smooth, and strong distortion.

Blackface - With the LP, these tubes had no character, but they handled bass very well. Nice strong bass. Fairly nice when distorted; balanced and not "flubby". With the Strat, these tubes were decent. There were no harmonic overtones, but the clean was nice and balanced. Position number 2 excelled. When distorted, again, they were fairly decent - balanced and not "flubby".


Tweed - With the LP, these tubes sounded brittle with lots of high end. These really didn't have a good clean sound. When distorted, they sounded "ratty". Perhaps these tubes would be good for a few "Stones" songs. With the Strat, they still had a piercing high end. When distorted, they sounded "ratty".

Blackface - These tubes performed better in this amp. With the LP, they had good harmonics. Very balanced clean sound. However, they were still "ratty" when played at full volume. With the Strat, They had a nice clean, especially on position 2 - good harmonics. But, still, they sounded "ratty" when distorted.

Brimar GT:

Tweed - Lots of upper mids and highs (but not piercing) using the LP. Sounds best on the neck pickup; very jazzy. Neck pickup was also good for fingerpicking. Smooth when distorted. Even though they had more upper end when played clean, they sounded bass heavy when distorted. That being the case, the bridge pickup seemed best. With the Strat, clean sound did not excel. Every pickup configuration sounded piercing. But when distorted, these tubes exhibited nice harmonics and smooth distortion.

Blackface - These tubes acted similar as they did in the Tweed. With the LP there was lots of upper mids and highs, so the middle and neck pickup configurations sounded best. Actually, I was getting quite a bit of chime with the LP. When distorted, they were pretty "flubby" in the bass. Also, there was nothing special about the distortion. With the Strat, the clean sound was decent, but piercing. When distorted, there was nothing special, just a 6V6 sound.

PhilipsECG GT JAN:

Tweed - Nice harmonics with the LP, but a bit "honky". When distorted, they sounded the same: nice harmonics, but "honky". With the Strat, these tubes sounded excellent in all positions. Nice overdrive with decent harmonics.

Blackface - With the LP, these sounded great in the middle pickup position. Good clean with decent harmonics. When driven, however, these tubes sounded "ratty". With the Strat, these tubes were not good. They were very brittle. When overdriven, they were still brittle.

Mazda GT:

Tweed - Great harmonics and string detail in all positions when played both clean and distorted with the LP. With the Strat, these had a very thick midrange. All positions were great! These tubes had a very detailed sound, because all playing nuances were revealed. Great harmonics when overdriven.

Blackface - One word: SMOKIN'! The LP sounded great in all positions with great harmonics. The Strat, although still sounding excellent, did sound a bit shrill in the bridge position. Great when overdriven with both types of guitars.

Visseaux GT:

Tweed - With the LP, these tubes were very detailed, complex sounding (3-dimensional), and perfectly balanced. When cranked, they offered an incredibly thick distortion. With the Strat, they were still just as luscious and detailed when clean, especially in positions 2 and 3. Position 1, however, was a tad piercing. Distorted, these tubes were just as excellent, except for a bit of mush in position 5.

Blackface - With both guitars, these tubes just sounded awesome both clean and distorted. I couldn't find any faults. In fact, I couldn't find any difference between these tubes and the RCAs. The Strat sounded particularly incredible when distorted.

Marconi/MWT GT/G:

Tweed - Fairly thick mids, but a bit "honky" when played clean with an LP. When distorted, these tubes were not that harmonically rich, but really seemed to concentrate on mids. With a Strat, these tubes were great. Excellent harmonics with very rich midrange. Both clean and distorted were excellent.

Blackface - Very nice clean sound with LP with a fair amount of harmonic richness. These tubes had the most distortion out of all 10 types with both types of guitars - very, very thick! These tubes had a perfect number 2 Strat position (in fact probably the best of all the tubes!). The other Strat positions were very respectable when played clean.


Tweed - Great balance (high, medium, and low) with great harmonics using an LP. Perfect when distorted, especially on the neck pickup. Smashing Baby! Incredible harmonics with the Strat when clean and distorted!

Blackface -Incredible harmonic richness and detail with both guitars when playing clean and distorted. I couldn't find any flaws here.


The best were the RCAs. No question about it! To be absolutely truthful, not only did I want the Visseaux to win, but I wanted to dispel the "urban legend" that the RCAs are the best 6V6. The Visseaux, however, became a very close second place winner.

The RCAs and Visseaux were very hard to differentiate, because they both had a similar and superior detailed sound, incredible harmonic richness, thick mids, and smooth and non-flabby distortion. If the Visseaux had performed a bit better on the Strat bridge position (when played clean) and the Strat neck position (when played distorted), they would have tied with the RCAs for first place.

The Mazdas, while still exceptional tubes, did not have quite the harmonic richness and complexity of the RCA/Visseaux. Therefore, they deserve a very respectable third place. If you consider cost an issue, these tubes probably deserve first place since you get 90 percent of the rich sound as compared to the first and second place winners for about half the cost.

The Marconi/MWT come in forth place. These tubes are great for Strat in either amp. They have a fair amount of rich mids and harmonic complexity, but not as much as the first 3 winners. These had an incredible amount (probably the most!) of distortion tone when played full out. Although very nice with an LP, they did seem a bit "honky" in some positions.

Instead of awarding the fifth through tenth places, I'd like to separate the remaining tubes into two groups: "Notable Mention" and "Decent Budget Tubes".

Tubes of Notable Mention - The Philips and Brimar fit into this group. Of these I favor the Philips a tad more because of their great Stratocaster abilities. The Brimar was still very good, most notably for their nice chime with the LP through the Blackface.

Decent Budget Tubes - I put the GE JANs, Russian, Chinese, and Groove Tubes HD in this group. This is not to say that these tubes are bad, because they are not.

Of all the tubes tested, I'd say the GEs were the biggest "let down". They didn't sound terrible, but they also didn't sound too much better than the Russian or Chinese. These tubes favored clean Strat playing through a Blackface configuration. Anything else was either too brittle or ratty.

The Russian and Chinese have their strength and weaknesses. But, if you're a broke college kid or on a strict budget, these two kinds of tubes are not too bad. The Chinese 6V6 seems to favor the Strat a bit more, while not depending on a particular amp configuration. However, if using an LP, these two tubes sounded best in a Blackface configuration.

The Groove Tubes HD functioned more like a 6L6 - with larger bass and a more "open" sound. Well, that's because they are a 6L6. As far as I know, these are cheap Chinese 6L6 Grove Tubes re-branded as 6V6. Although sort of lifeless, they had a good clean sound with both guitars and both amps. Nothing was piercing. The distortion sound was also not half bad.

Hope this is helpful to some people.

Thanks to Kevin Miller aka "Mook" for doing the testing and sharing the results with us in alt.guitar.amps .
Last updated: 27 December 1999
Taste Test copyrighted by Kevin Miller aka "Mook" 1999. Incidentals copyright 1999 Miles O'Neal, Austin, TX. All rights reserved.
Miles O'Neal <> [remove the "XYZZY." to make things work!] c/o RNN / 1705 Oak Forest Dr / Round Rock, TX / 78681-1514