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Topic: New 6L6's for a Pro Reverb |
Jack Stoner
From: Kansas City, MO
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Posted 10 Oct 2017 2:24 am
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Our lead guitar player asked me about replacement 6L6's for his mid 60's (blackface) Pro Reverb. I haven't been into tube amps for a long time and don't know what is "good" that won't break the bank. To tell how long its been, when I was working as an amp repair tech the RCA's were still being produced and what I used.
I know I tried several 12AX7's in my Carvin BX500 and the Tung Sol's sounded terrible but the Groove Tube is working out.
Thanks _________________ GFI Ultra Keyless S-10 with pad (Black of course) TB202 amp, Hilton VP, Steelers Choice sidekick seat, SIT Strings
Cakewalk by Bandlab and Studio One V4.6 pro DAWs, MOTU Ultralite MK5 recording interface unit |
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Mark Fowler
From: Minnesota, USA
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Posted 10 Oct 2017 3:49 am
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The wonderful world of valves.
After trying many NOS and new production tubes I usually use JJ tubes for both preamp and power sections.
There are quality issues in all new production tubes but that's just how it goes now days, new production tubes can be hit and miss.
If your maintaining your own tube amp and only have one or two I would seek out NOS RCA etc. However; since I build and repair amps I have to use new production tubes.
Some EH, Sovtek, JJ, Shunguay, Valve Arts, Northern Electric, and Mullard can be good choices.
Mark |
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MIchael Bean
From: North Of Boston
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Jerry Overstreet
From: Louisville Ky
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Posted 10 Oct 2017 8:48 am
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Maybe check with Ken Fox. He replaced my 6V6 bottles with new JJ's. I can't say he recommends JJ's for 6L6's however. |
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Michael Butler
From: California, USA
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Posted 10 Oct 2017 9:03 am
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i've been using the jj 6l6 and find they sound really good and last a long time.
i'm enclosing a 6l6 tube review by the tube store. i've purchased from them but i've also purchased from amplified parts/antique electronics/tubes and more(basically the 3 are the same company in arizona).
http://www.thetubestore.com/6L6-Tube-Reviews
play music! _________________ please see my Snakeskin's Virtual Music Museum below.
http://muscmp.wordpress.com/ |
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Ed Boyd
From: Illinois, USA
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Posted 10 Oct 2017 10:18 am
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I use Mesa Boogies in everything. They may not be the best but they really really test their tubes. Mesa disposes of a lot of tubes because they are not spec.
Mesa tubes have to be spec because Randy doesn't put bias controls on their amps so the tubes have to be spec. Allowing customers to change the amp's bias created a lot of tech support issues because guitar players eff up their amps jacking with the bias. |
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Mark Fowler
From: Minnesota, USA
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Posted 10 Oct 2017 1:42 pm
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I build a lot of amps and sell a lot of tubes and my number one selling brand is JJ, but I also like many other brands so it's very subjective which brings up what I do often "tube rolling" to find what sounds best.
Mark |
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Jack Stoner
From: Kansas City, MO
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Posted 10 Oct 2017 2:30 pm
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I ordered a matched set of JJ's for him. I may have to adjust the bias. It was set the last time I worked on it (recapped the power supply about 2 years ago). He's got lots of amps, two other Pro Reverbs among others but this one is his favorite and what he's used ever since I started working with him around 98. I've repaired it a couple of times. _________________ GFI Ultra Keyless S-10 with pad (Black of course) TB202 amp, Hilton VP, Steelers Choice sidekick seat, SIT Strings
Cakewalk by Bandlab and Studio One V4.6 pro DAWs, MOTU Ultralite MK5 recording interface unit |
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Godfrey Arthur
From: 3rd Rock
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Posted 14 Oct 2017 11:04 pm
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The best 12AX7 made was the Telefunkens. Achtung!
Tung Sol was a great company when made in the USA but these days they have reliability issues.
A single made in USA old stock 6550 power tube made by Tung Sol in the USA can go for $300 a tube!
Chris at Parts Connexion up in Canada has some made in USA tubes for sale, not jacked up in the price area. An "estate blow out" so you might check there.
I have purchased some parts from Chris. And he does sell a wide variety of esoteric audiophile items, caps. When you go to his website you'll get the idea.
http://www.partsconnexion.com
He has Telefunken 12AX7's and some RCA and GE 6L6's.
He does have Groove Tube items.
But keep in mind Groove Tube is a re-brand.
Best to check with the list:
http://www.partsconnexion.com/t/eblast/2015/estatetubes.pdf
But if you want lower cost Russians, the Sovteks seem to last the longest if longevity is your priority.
Some amp repair guys are leaning Shuguang tubes made in China.
You can get a matched quad of 6L6's for $60 off eBay; comes from Taiwan but they offer free international shipping.
http://www.ebay.com/itm/SHUGUANG-6L6GC-6L6-6L6GCR-NEW-PLATINUM-MATCH-QUAD-/270799279854
Shuguang 6L6GC matched quad. _________________ ShoBud The Pro 1
YES it's my REAL NAME!
Ezekiel 33:7 |
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Dan Robinson
From: Colorado, USA
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Posted 16 Oct 2017 7:44 pm
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Jack Stoner wrote: |
I ordered a matched set of JJ's for him. I may have to adjust the bias. It was set the last time I worked on it (recapped the power supply about 2 years ago). He's got lots of amps, two other Pro Reverbs among others but this one is his favorite and what he's used ever since I started working with him around 98. I've repaired it a couple of times. |
Jack, I replaced the original GrooveTubes in my Fender HR Deluxe with the JJ 6L6s. Bias adjustment was absolutely required. After an hour voltage at the test point had drifted, had to re-adjust.
edit for more info...
Don't know if there's a resistor in line where you could measure voltage drop to calculate bias current. Might not matter, IIRC the 60's Pro Reverb has a fixed bias supply. |
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Jack Stoner
From: Kansas City, MO
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Posted 17 Oct 2017 2:10 am
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What I have done, and it may not be correct but what I do, is take the fixed side voltage (e.g. -51VDC) and adjust the other side the same. Seems to work out OK.
He isn't going to let me adjust it right now. I gave him the tubes last night at our Monday evening gig and he replaced the old tubes before the show. He was really happy with the sound he had last night. I told him it really needs adjusting but he said "not now". _________________ GFI Ultra Keyless S-10 with pad (Black of course) TB202 amp, Hilton VP, Steelers Choice sidekick seat, SIT Strings
Cakewalk by Bandlab and Studio One V4.6 pro DAWs, MOTU Ultralite MK5 recording interface unit |
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Tommy Boswell
From: Virginia, USA
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Len Amaral
From: Rehoboth,MA 02769
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Posted 17 Oct 2017 1:59 pm
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Genuine Fender matched set of 6L6 tubes. $29.99
Rondomusic.com click on parts and bodies |
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Dan Robinson
From: Colorado, USA
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Posted 17 Oct 2017 10:43 pm
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Good resource for tubes.
http://www.eurotubes.com/store/pc/home.asp
The tubes I bought were thoughtfully packed, came with printed info on handling and installation that I found helpful.
Jack, seems that your guitar player is happy with them. It will be a surprise if that amp visits your bench again.
There must have been mfg. variation, even back when valves were made in the U.S.A. Amps had fixed bias supplies, and things worked OK. |
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Bruce Derr
From: Lee, New Hampshire, USA
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Posted 18 Oct 2017 2:53 pm
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Dan Robinson wrote: |
IIRC the 60's Pro Reverb has a fixed bias supply. |
Fixed bias can be a confusing term. Technically it just refers to biasing a tube by applying a fixed negative voltage to the grid and grounding the cathode (as opposed to cathode bias, the other common method). All Pro Reverbs were indeed fixed bias, but the blackface ones did have a bias pot for adjusting the bias voltage. In '68 or '69 Fender changed that to a bias balance control and made the bias voltage otherwise unadjustable. |
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