Let Me Roll It...NOS

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Too Many Notes
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Apr 26, 2012
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Tubes to roll...

Finding that Winged C EL34s were an NOS thing as of last year, I figured I'd get a set or two for spares, but was shocked at how expensive they've gotten. Yes, they're good sounding tubes for recent production. But at recent prices, there are more desirable NOS out there. Worse still, there are lots of factory second Winged Cs floating around on the NOS market.

So I decided to keep an eye out for other good NOS tubes for my HXDA - the DG30 already has NOS preamp and power tubes, as well as a spare set of NOS power tubes.

I lucked out, finding a lovely set of NOS Siemens EL34s for about the same price as the Winged C, and the icing on the cake is that I scored an NOS CV4004 (12AX7) Mullard at a not-too-terrible price from a vendor I trust. CV4004 means that the Mullard is a military-grade tube, with tighter tolerances than usual production. The Mullard will go in the V1 of the HXDA; I may or may not go with BRIMAR in the other two preamp positions, or I may stick with the JJs it came with. I guess trial and error will judge. One thing about the BRIMARs is that they can be a bit iffy in terms of signal strength and some are unacceptably noisy. I only have a couple left, and this pair are two that didn't make it into the DG30 as they didn't sound as good as the two that are in there now. I don't know how they'll sound in the HXDA, so I'll try 'em at the least.

If neither the remaining BRIMAR tubes nor the JJs meet expectations, I'll order a couple of NOS RFT (East German tubes), as I understand they're very capable in an amp like the HXDA, though a little dark. However, that would be fine in my HXDA, as long as they aren't noisy or weak, since I like a warmer sound, and I tend to turn the treble down in that amp as it is. They're about a third the price of an NOS Mullard, so I guess they're kind of a bargain in NOS-World.

I'm saving the Siemens EL34s for eventual replacement of the Winged Cs, as the amp was built this year, and has gotten pretty light use, sharing time with the DG30. So the Winged Cs are still very strong and sound "as-new."

It'll be interesting to see how this all comes together. With any luck, I'll have the killer-diller sound I'm hoping for (obviously the amp already sounds great, this is to make it sound even better!).
 
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I recently burned out the tubes on both my MDT and Archon. I suspect I'm doing something wrong. What is the correct turn-on and turn-off sequences? And at which points in the sequences should I be sure to have a guitar plugged in (I have a speaker plugged in even in standby mode, that's not a problem, I rarely switch speaker cabinets, but I often switch guitars, and I wonder if I should turn the whole amplifier off between guitars or not)? I'm deliberately not stating what I do so that I don't spread misinformation.

I have a friend who collected tubes, but now he has way too many spares. His trick was to buy batches to find the really good tube buried in someone's grandpa's inherited collection from someone who had no use for -- and more importantly, no knowledge of -- what they were selling.

Of course, now he's stuck with a bunch of crap, because he knows they (the non-buried-treasures, the "chaff" as it were) are worthless, and he's honest enough not to sell it as anything but (also too lazy to put anything on the market that has little return value -- for which I don't blame him).

I mention this because I'm still looking for that good-return-value method of finding good tubes. Back in the early oughts, when I was searching for tubes, I tried a bunch of different new production tubes. My favourites were Ei gold pin Elite EL84 tubes. Now all I can seem to find are 12AX7 tubes.

Sidebar: anyone know what the tube complement for the MDT is? "MDT" appears to be too short a search term for the forums, and "site: prsguitars.com mdt tube complement" isn't turning up anything useful. I'll email customer service, perhaps they have a soft copy of the manual archived somewhere that I'm not finding.

I will follow this thread with interest.
 
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What is the correct turn-on and turn-off sequences?

Power up the amp so that it is in standby mode when you switch the amp power on. After the amp warms up a bit (PRS recommends a couple of minutes to lengthen tube life), switch the standby to the position where the amp will play. I'm saying it this way because there is often some confusion as to whether the standby is "on" or "off" when the amp isn't making noise.

Powering down, I switch into the standby mode first, then switch the amp's power off. Some players don't feel a need to do that, and just switch the amp off.

And there are lower powered amps - my Roccaforte Rockie being one - that don't have a standby mode in the first place. You really don't break anything not using a standby on an amp that has one, you just shorten the tube life.

With any amp I turn the master volume down before switching the amp on or off to prevent accidental noise issues, and on non-master volume amps like the Rockie, I just turn the channel volume to off.

The purpose of the standby mode is simply to warm the tubes up to operating temperature, however, I use it also as a fail-safe to prevent loud pops when plugging in a different guitar, etc.

I always switch an amp to standby when plugging in a guitar, or unplugging one, but that's to save my ears from loud pops, and probably has little to no effect on tube life.

I mention this because I'm still looking for that good-return-value method of finding good tubes.

I'm not sure there's such a thing as a truly good 'return for value' on stuff like NOS tubes. After all, the prices on some of them have gotten very high; for example, there are Telefunken preamp tubes that go for $2000 apiece. New in the 60s or 70s, they might have cost a dollar or two.

On the one hand, that's crazy, and on the other hand, if you've got a vintage Telefunken microphone worth $15,000 and you want to keep it sounding the way you love it to sound, you just might think it's worth it. Then again, the new price of the mic would have been only a few hundred bucks, too...

My own thinking is this: when it comes to tubes, they aren't making the really good stuff any more (or maybe they aren't making it yet because who knows what the future holds?). So people get as high a price as the market will bear. Sure, you can buy new manufacture tubes, and make a small compromise in the sound. My HXDA still sounds damn good with its complement of new tubes. So if one thinks of it in terms of paying 20 times the cost of a new JJ for a good NOS Mullard, there is no return on value. It's a crazy thing to do, and only a die-hard crazy would do it.

Then again, I'm that guy. It's really an enthusiast thing, more than it is a sensible person thing.

I buy from tube shops that have a warranty period, usually 90 days on NOS tubes. There's no way I would want to sort through a crapload of junk to fish for a couple of gems, though I understand why there are folks who like to do that.
 
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Ah. So the 3-way position switch is probably preferable for people like me, whereas the two single-stroke switches just confuse me -- I was definitely doing it wrong. Thanks for that.

And yes, it's definitely at the point of dimishing returns -- I probably should have said "optimal method for obtaining the best tubes for the best price", or something to that effect.

I should probably practice with cheap(er) new production tubes, and save the good stuff for recording. Thanks for all the advice, as always.
 
Oh, hey, now that I'm turning it on properly, I may not have burned out my tubes. Cheers!
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Les, you should have fun with the Mullard in V1. I've had one in that spot in the SuperD for a year and love it. However, I've not dropped in an RFT and that certainly would be interesting, if it doesn't mute the beautiful cleans of this amp. That's always the compromise. On the Boogie, I kept an RFT in V3 to flavor only the lead channel and it did a great job. You can see why Diezel likes them in their amps.
 
Les, you should have fun with the Mullard in V1. I've had one in that spot in the SuperD for a year and love it. However, I've not dropped in an RFT and that certainly would be interesting, if it doesn't mute the beautiful cleans of this amp. That's always the compromise. On the Boogie, I kept an RFT in V3 to flavor only the lead channel and it did a great job. You can see why Diezel likes them in their amps.

I really am looking forward to installing the Mullard when it arrives. With any luck, it'll be worth the dough, like the BRIMAR tubes were.
 
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Markie, your collection has to be awesome! It'd be cool to see photographs of each guitar - I've only seen recent stuff you've posted from time to time.

The Markie Collection Coffee Table Book would be hella incredible!
 
C'est arrivée.



Triodes nicely matched, picked for low noise and microphonics. Should sound very good, indeed!

I will report back - will be installed later when I get back to the studio, and I'll test it for a couple of days before the tone report. Proper labeling and date codes, too! :top:
 
Interestingly enough, when I went to put the tube in my box o' valves, I discovered that this at-least-38-year-old tube measures stronger than a pair of new-manufacture JJ ECC83s tubes I got from the same vendor. And the JJs are tubes that measure pretty strong in relation to other new-manufacture tubes. Go figure!

I think I'm changing the name of my box o' valves to Box O' Rock. It's so much more fitting! ;)

I've managed to assemble an amp or two's worth of very nice NOS tubes!
 
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I installed the NOS Mullard 12AX7 in the HXDA's V1 position today, and I also decided to install the two gold pin JJs that were also tested for microphonics, noise and triode balance that I had on hand.

I did this because I previously noticed an occasional hum, and sputtering from one of the stock JJs, and wasn't in the mood to figure out which one was doing it. I figured, let's just start fresh and tackle the whole ball of wax at one go. I figured the tested JJs would be an improvement on the stock tubes, and they were. Or I should say, they fixed the occasional problem I'd been having. And they're very quiet. So is the NOS Mullard, as it was also tested for low noise, microphonics and triode balance.

Here's what I've noticed that the Mullard changed:

Some readers may remember that I thought my old 50 Watt HXDA sounded a bit warmer and more syrupy than the 30 Watt HXDA I now have. Well, the 30 now sounds like the 50 in that department. The low end is better, the lower midrange has that wonderful "give," and the highs are noticeably sweeter. With the Mullard in V1, there is a warmer, richer, and dare I say it, more "vintage" tone to the amp. It sounds right.

When the amp goes into gain and grit, there is a smoother, more gradual transition, too. There is sweet overdrive, and although I never thought my HXDAs were harsh in any way, this is a sweeter kind of breakup than either the 50 or 30 (with JJs stock).

These are the qualities I had hoped for; the amp sounded great before, now it's just that much nicer. So I couldn't be happier! :2channelh:
 
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Sweet.

It's probably wise to try them now, anyway, I almost said something, you don't want to wait until months down the road to try newly purchased tubes.
 
I got a good reminder tonight how much the right tubes can matter.

Last month or thereabouts I brought home a shiny new 2 Channel Custom 20 combo. I'd tried one a few months ago that wasn't for sale, but really liked it. The local music emporium got one in, so I went down there with card in hand, played it enough in the store to make sure it was functioning OK, and brought it home.

And it didn't take me long to realize I was not in love...

The clean channel was fine (no surprise there). But I was not getting along with the lead channel. It seemed harsh and "blatty" to me, for lack of a better word. I wanted to blame the speaker (G12H30, not yet broken in), because it did sound better plugged into some of my other speaker cabinets.

But still I wasn't quite feeling the love from that lead channel. Tonight I was playing around with it, surfing this forum and realized that it sounded fine to me if I had the volume knob on the guitar down. As long as it was below 7 or so, things were fine. Up to 8 or above, and that blattiness came back. Hmm..

Les' posts about tube rolling and NOS tubes were swirling around in my head, especially the one where he mentioned gain differences between different preamp tubes. Hmm.. Maybe less gain in the lead channel would be the ticket.

So I went rummaging around in my preamp tube stash and came up with a few goodies. I'd previously replaced a couple of JJ ECC83s with modern Tung-Sol 12AX7s, though when I looked closely at the tube sockets, I realized I'd left the stock tube in the first preamp tube socket, which wasn't deliberate.

So I went with Input Tube: Tung-Sol 12AX7, Red Channel Tube: JJ ECC803S, Blue Channel Tube: Tung-Sol 12AX7. I also swapped out the stock phase inverter tube for an old-manufacture Mullard CV4024 (12AT7 equivalent).

Result? Happy camper! The harshness I hated was gone, and the lead channel was bright, round, and smooth, the way I wanted it. Pretty good for my first crack at it. As long as those tubes don't make a lot of extra noise, I'll probably leave it as is. The good news is that none of those tubes are very expensive. The Mullard CV4024 is about $40 now (they were $24 when I bought them), but that's the most expensive one of the lot.
 
These are the qualities I had hoped for; the amp sounded great before, now it's just that much nicer. So I couldn't be happier! :2channelh:
Excellent. Mission accomplished. :cool:

(I'm also a little relieved. I feel a bit responsible for your expectations and I was worried about possible disappointment. *whew!*)
 
Glad you like your amps after the roll! Tubes can be so hit or miss. A good referenced is upscale audio.com who sells a lot of the vintage tubes and gives great descriptions of the different tubes. Not surprised the amp sounded better with the vintage Mullard vs. the JJ's. I think JJ's are still in production in Yugoslavia so they are used on a lot of tube based amps and pre-amps vs. the Mullards are fairly rate and expensive when you find them.
 
I got a good reminder tonight how much the right tubes can matter.

Last month or thereabouts I brought home a shiny new 2 Channel Custom 20 combo. I'd tried one a few months ago that wasn't for sale, but really liked it. The local music emporium got one in, so I went down there with card in hand, played it enough in the store to make sure it was functioning OK, and brought it home.

And it didn't take me long to realize I was not in love...

The clean channel was fine (no surprise there). But I was not getting along with the lead channel. It seemed harsh and "blatty" to me, for lack of a better word. I wanted to blame the speaker (G12H30, not yet broken in), because it did sound better plugged into some of my other speaker cabinets.

But still I wasn't quite feeling the love from that lead channel. Tonight I was playing around with it, surfing this forum and realized that it sounded fine to me if I had the volume knob on the guitar down. As long as it was below 7 or so, things were fine. Up to 8 or above, and that blattiness came back. Hmm..

Les' posts about tube rolling and NOS tubes were swirling around in my head, especially the one where he mentioned gain differences between different preamp tubes. Hmm.. Maybe less gain in the lead channel would be the ticket.

So I went rummaging around in my preamp tube stash and came up with a few goodies. I'd previously replaced a couple of JJ ECC83s with modern Tung-Sol 12AX7s, though when I looked closely at the tube sockets, I realized I'd left the stock tube in the first preamp tube socket, which wasn't deliberate.

So I went with Input Tube: Tung-Sol 12AX7, Red Channel Tube: JJ ECC803S, Blue Channel Tube: Tung-Sol 12AX7. I also swapped out the stock phase inverter tube for an old-manufacture Mullard CV4024 (12AT7 equivalent).

Result? Happy camper! The harshness I hated was gone, and the lead channel was bright, round, and smooth, the way I wanted it. Pretty good for my first crack at it. As long as those tubes don't make a lot of extra noise, I'll probably leave it as is. The good news is that none of those tubes are very expensive. The Mullard CV4024 is about $40 now (they were $24 when I bought them), but that's the most expensive one of the lot.

Awesome that you made the switch and discovered how good the amp can be!
 
Excellent. Mission accomplished. :cool:

(I'm also a little relieved. I feel a bit responsible for your expectations and I was worried about possible disappointment. *whew!*)

Happy with this swap, sir! Thanks for the tip!
 
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