Ampeg V4B- the good, the bad, and NOS tubes

[alexchavel]

While i agree with you that there are excellent new amps being made today, the early 70's v4b I just purchased has really taken my joy of playing to a new level the last few weeks...

Old P bass + old v4b + old 8x10 = tone bliss

It's just the sound I've always wanted, and even the band is feeling the difference.

This head kicks serious ass

 

[alexchavel]

And I've been locating tubes for this beast with ease and at decent prices, well worth it for the smile on my face!

 

[Gabriel L'Heureux]

Just purchased a early V4-B and totally agree with alexchavel ! Im in tone heaven right now ...

4 JJ 7027A installed and one 6K11 Magnavox

What can you guys say about these ?
Planning on touring a little with this rig. What should I get for replacements and where ? (Live in Montreal BTW)

 

[JimmyM]

Just purchased a early V4-B and totally agree with alexchavel ! Im in tone heaven right now ...

4 JJ 7027A installed and one 6K11 Magnavox

What can you guys say about these ?
Planning on touring a little with this rig. What should I get for replacements and where ? (Live in Montreal BTW)

Well you have to get 6K11's NOS. There are a few brands...don't know that it matters so much. I'd never pay what they want for NOS power tubes so I'd stick with JJ's. 12ax7's and 12au7's I'm using JJ's in my HSVT-CL and V4B reissue, and I've also tried Tung Sols, which are brighter than JJ's and I didn't like it quite as much but it might be cool in an old V4B. For a 12dw7, do NOT get the JJ. It's crap. Go NOS. Any of them are pretty good.

But if your amp is tone heaven right now, save your money and leave it.

 

[waltdogg]

The only thing I'd suggest is take it to a tech that's good with V-4's get your tubes tested and the amp recapped if it hasn't been in the last 5-10 years. V-4s sound just right with JJs, NOS helps if you're a complete tone sniffer.

 

[khangurumc]

I put a quad match of TAD 6L6GC-STR in my V4B and instanly love it.For the 6k11 I have a Tung Sol and 3 Westinghouse.The Tung Sol is taller than the others,and prefer the westinghouse.
This amp sound so good.Im in tone heaven too!Any word can describe it.

 

[jastacey]

The 12DW7 tube in the old V4B can be swapped out for a 12AX7 ...there was a service note from MTI when they owned "Ampeg" and they just said swap out the 12DW7 with a 12AX7 ...provided your not going to use the "slave out jack"

 

[JimmyM]

The 12DW7 tube in the old V4B can be swapped out for a 12AX7 ...there was a service note from MTI when they owned "Ampeg" and they just said swap out the 12DW7 with a 12AX7 ...provided your not going to use the "slave out jack"

MTI never made a V4B. You're probably right that you could use the 12ax7 and skip the slave out jack, though, but there's no reason to do that when 12dw7's are still commonly available.

 

[jastacey]

Your right about MTI not making the V4B ... but back at that time, there was a shortage of the 12DW7's and when they made the SVT they changed the 12DW7 circuit to use the 12AX7 and they had a service letter on it .... and your right, now you have some choices of 12DW7's

 

[B-string]

I tried the 12AX7 drop-in for the 12DW7/7247 with my V4-B. It did something I just didn't like with the amp's tone. Always went back to a 12DW7.

 

[waltdogg]

I order JAN Philips military grade 12DW7s from fliptops. But I have JJ on reserve in case the JAN tubes ever go out. Which I had to do, because the last JAN 12DW7 I ordered from them was installed, tested once but it went microphonic in the past few months.

 

[coreyfyfe]

I order JAN Philips military grade 12DW7s from fliptops. But I have JJ on reserve in case the JAN tubes ever go out. Which I had to do, because the last JAN 12DW7 I ordered from them was installed, tested once but it went microphonic in the past few months.

I've got a few of those as well that I got from AES. Have one in the PI position of my SVT. Been having a fair amount of noise trouble with some other JAN stuff (6C4WAs, 6188s) that surprised me. Would have expected better quality with JAN stuff...

 

[B-string]

6C4s were mostly used as local oscillators or class C RF amps, finding quiet ones is a challenge. They didn't see much audio band use so attention to microphonics was not a high final test priority. I had to buy at least 5 to get an "acceptable" one. Just the nature of that tube.

 

[waltdogg]

Yeah I've had a slew of JAN 12AU7 and 12AT7s that were all bad. That was really annoying as I was just trying to get my phase inverters squared away.

 

[DavidEdenAria]

Yeah I've had a slew of JAN 12AU7 and 12AT7s that were all bad. That was really annoying as I was just trying to get my phase inverters squared away.

The good news with 12au7 is they are very abundant in NOS or slightly used NOS for cheap....same with 12at7 to a certain extent.

 

[DavidEdenAria]

I've got a few of those as well that I got from AES. Have one in the PI position of my SVT. Been having a fair amount of noise trouble with some other JAN stuff (6C4WAs, 6188s) that surprised me. Would have expected better quality with JAN stuff...

I've purchased tubes from AES in the past....I never trusted them for thoroughly testing tubes in years past at least....don't know what their testing procedures are currently though.

Otoh, I bought a bunch of metal can 6SC7 for my 48 Fender Deluxe amp for dirt cheap from AES expecting maybe 1 or 2 to be quiet.....I have maybe 6 now that seem almost dead quiet which can be very rare for metal can 6SC7.

 

[B-string]

AES will accept and credit you for excessively noisy tubes. You pay shipping, but there is no hassle so long as it is not broken in transit on return.

 

[chadds]

Those old tubes made it through WWII.

They also could take that hard banked turn in your B-52 with that mushroom cloud in the port windows. You've just brought a millenium of craze to that foreign land, heading home now for steak and beer.

Making great musics in your pre or head are the least they can do to justify their existence.

 

[coreyfyfe]

I've purchased tubes from AES in the past....I never trusted them for thoroughly testing tubes in years past at least....don't know what their testing procedures are currently though.

Otoh, I bought a bunch of metal can 6SC7 for my 48 Fender Deluxe amp for dirt cheap from AES expecting maybe 1 or 2 to be quiet.....I have maybe 6 now that seem almost dead quiet which can be very rare for metal can 6SC7.

I've had no trouble with AES and have actually scored some pretty good old stock stuff from the on a few occasions (got the last of their 6K11 selection a few months ago for half the price of most other vendors). I know they offer a burn-in on power tubes in addition to their standard matching for a couple dollars per tube or so. Not quite as good as the matching done by TC (for no additional cost) but better than some other sellers.

 

[beans-on-toast]

I've purchased tubes from AES in the past....I never trusted them for thoroughly testing tubes in years past at least....don't know what their testing procedures are currently though.

I buy tubes there from time to time but I test them after receiving them.


They offer a good selection of tubes but I don't think that they do much more than use a tube tester when matching tubes. I don't believe that they even test the singles that they sell. If you have an issue, they will send you a new one but they leave it up to you to find the problem. They are not alone in doing this, a lot of companies operate this way. As you can see below if you buy a matched set of NOS tubes, they only match them if they have sufficient stock of the same make of tube. They sell selected pre packaged matched sets. I believe that they buy them that way.


From their web site:

We match current production power tubes based on plate current and transconductance. We charge an additional $1.25 per tube for matching. Due to the difficulty of finding NOS tubes that match brand and ratings, NOS tube matching is $2.50 per tube. They are matched for transconductance and, if possible, we also match them for plate current.