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EF86 swap for 6BQ5 reverb?

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Greetings. I am new here to this site, so am looking for some help/hints.

I am a professional harmonica player and have three amplifiers that I use regularly. One is a very vintage 1941 Gibson EH-125 that works great and that I have kept as unmodded as possible.

I have a new Blackheart BH15H that I have swapped all tubes for better tone for harmonica.

The one I have this question about is a 1973? Traynor YGL-3 Mark III that I have extensively voiced for harmonica.
The original layout had five 12AX7A/7025 pre-amp tubes, a 6BQ5 reverb that is listed as V5, but is actually the third tube after V1 ( Ch.1 pre-amp/clean ) and V2 ( Ch.2 pre-amp/effects ).
The four power tubes are 6CA7/EL34's.
I have swapped all pre-amp tubes for better tone and less feedback.
V1 & V2 are 6211's, V3 (tremolo) is Philips 7025, V4 ( driver ) Sylvania BP 12AY7, for V5 ( reverb ) I had been using a Chinese EL84 or an RCA 6BQ5, V6 ( phase inverter ) Euro 7247 Mullard?
I bridge the channels, so am using all power tubes.
The unit sounds terrific, and I used it earlier this month for a high profile gig where we opened for a national touring band that features a top harp player. After hearing my sound, he complimented the rig.

Anyway, I recently acquired a Mullard EF86 with shiny nickel plates...along with some other tubes. I did not think that I could use it, but after investigation, it would seem plausible that i could use this as a sub for the reverb in this amp. I don't use alot of reverb, but like just a little for flavor. The situation is that with what I was using, reverb was barely noticeable up to ONE, and then it is too much...like playing in a cave or underwater, so I usually have it zeroed.
I decided to try out this swap experiment, with plenty of kill switches and other safety precautions. After letting the amp warm up sufficiently and with my mic hooked up, I first did the microphony test with a chopstick. Tapping the tube produces some chimey noise, but it is not all that unpleasant. No noticable noise when just played regular.
First off, reverb is now manageable...almost hard to hear. What was surprising was how much the tremolo jumped out, that sounds real nice and provides much more signature for my style of harp playing.

I played around with this for about a half hour and everything worked well.
Is this a reasonable swap? Anything to be concerned about?

Thanks for any help.
 
Hey Quidnuncle,

Totally wacko to use EF86😉. It does not in any way have the current capablity to drive the reverb-tank. Your EL84 is a great reverb-driver. We use either ECL86 or EL84 in our amps.

The odd thing about Traynor is they use direct-drive to a HiZ tank. If you want to upgrade, go for a long LoZ 3-spring tank and a Fender-style reverb-transformer.
 
Thanks Lars, I have a variety of good used EL84's around that I'll try. Picked up the EF86 for a fair price, so I can turn around and sell it to someone that can use it and maybe subsidize some of my other tube purchases. HA!

Have some tri-mica Sylvania 5814A's coming in that I'm anxious to try in the 2X12 beast in V1 & V2 for increased headroom.
 
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