A note on 6386 replacement tubes

[Lawrocker]

To pile on to the sentiment, the JJ 6386s don't last for very long, just like their 12AX7s, 12BH7As or any other tube I have used of theirs. The 'unfairchild' was designed around the JJs and they have adjustments that seem to compensate for the difference. Just be prepared to lay down a couple hundred dollars every few weeks as the tubes fade.

 

[soapfoot]

I assume the new Heritage Audio 670 copy is using them as well? Or are they using some kind of t-bar solution?

 

[waltzingbear]

I should take this moment to remind people that the original 6386 in a 670 did not last long either. In a Sta Level they would last quite a while ( no matching between sides ) and nobody expected anything but crunch from them. Bob Ohllson (sp?) complained about changing tubes several times a year in the Fairchild.

 

[emrr]

I should take this moment to remind people that the original 6386 in a 670 did not last long either. Bob Ohllson (sp?) complained about changing tubes several times a year in the Fairchild.

....as did Cosimo Matassa.....

 

[iampoor1]

Isn't owning a Fairchild sort of like owning a ferrari? Yeah the expierence is amazing but 13k brake jobs and replacing the clutch every 10k miles is all just part of the existence if yoh want it to work "just like new". Of course...I own neither....just thinking out loud

 

[mjrippe]

To pile on to the sentiment, the JJ 6386s don't last for very long, just like their 12AX7s, 12BH7As or any other tube I have used of theirs. The 'unfairchild' was designed around the JJs and they have adjustments that seem to compensate for the difference. Just be prepared to lay down a couple hundred dollars every few weeks as the tubes fade.

The JJ 6386 that I have come across tested lower when new than the vintage ones I had. So that *may* point to shorter useful life. As for 12BH7, there is no decent new manufacture that I have seen yet. Fortunately NOS can be found for the same price or less. Not so much with 6386.

 

[Big G]

I realize this thread is very old, but I am experiencing the exact meter discrepancy you are having with JJ’s. ~10db of gain reduction on the meter with only 5db of actual GR. My build is brand new (newly completed Drip V2) and otherwise functioning perfectly. The JJ tubes test and sound fine. Curious if there is any workaround for this issue or if this is actually normal behavior?

Just chiming in too ihearttubes, it is an old thread ;-), certainly not disagreeing with troublereports point, but like you I have a DRIP V1, full of JJ's - working flawlessly for years.
Although I did buy all tubes from someone who handpicked and matched as best they could, so i paid extra for that service.

Don't sweat the VU problem, i spent an hour on the phone with Greg (DRIP) on VU's, its a rabbit hole, and seems its just a fundamental challenge with even the originals. I just let the VU's be, and use my ears 1st then look at my console and DAW meters to get the gain reduction i want.
I just allow my Fairchild to be old and graceful in the rack, and let the meters dance around as a form of entertainment.

I can hear what it does, and I just dial it in and out to what I like ;-)

but I get in a measurement world, that kind of thinking isn't acceptable.

#privilegedtohaveanyfairchild

 

[gyraf]

its just a fundamental challenge with even the originals

Only if you can't get good 6386 tubes - differences in meter reading comes from flawed current/Gm behavior in the tubes themselves, nothing to do to correct that here. Note: This mismatch also messes with your ratios.

And even if you pay for matched new-production tubes, you only get them "matched to each other", not at any even remotely absolute precision. I have a strong suspicion that JJ traces and selects heavily already from factory, and send the few good ones to PR-heavy customers (thereby upping their apparent quality)

 

[joshua]

If only Larry Janus had enough interest to build more tube-matching set-ups.

 

[joshua]

Thinking about this, there are more than a few tube heads here making products for the market. I think the hurdle for Larry is, in order for him to make his tube matching setup into something he'd sell, he'd need enough investment to make the effort worthwhile - no mystery there. EveAnna wants one, if a few of you also wanted one, there could be enough interest to make it worth the effort to elevate the setup he made (and showed at one AES long ago) to something bullet proof and sellable. His setup takes 20 tubes at a time, plots curves, puts the matches together, checks microphonics, does the full kaboodle. How many would benefit from this enough that they'd spend money to have their own setup?

 

[emrr]

Still not a big market, still the territory of manufacturers cobbling together for their own needs.

We don’t even have anyone offering the matching service for others that I’m aware of.