Tube Amplifiers

Mike Schwartzman · Post by **Mike Schwartzman** » 22 May 2009 6:34 pm

Yes indeed...plug and play...I like that too! But I must say this has been a very informative thread. Thanks to all...I've been really enjoying all this info.

I'm neither an audiophile or an electrical engineer, but I have worked on my share of guitar tube amps over the years and Bill, it's really not that complicated. I have an older Bandmaster Reverb that only has 2 ea. 6L6 power tubes that I play thru a Weber Ceramic 15" speaker. All that was required was changing the preamp tubes (V1, V2) from 12AX7's to 5751's and using a good pair NOS 6L6 power tubes just as Dave M said in his post. It's absolutely beautiful for pedal steel...Maybe not for every gig, but certainly for small gigs and for recording...superb. It's now plug and play also. So really all it involved was changing tubes. It can be made even cleaner, but that's been discussed well here already.
The Bandmaster Reverb is a stock 1973 Silver Face Fender that I "Black Faced" years back and it still sounds great with PSG. Very loud & clean up to about 5 or 6 on the volume pot. Good for 6 stringer too.

James Morehead · Post by **James Morehead** » 22 May 2009 6:57 pm

Bill Duncan wrote:Good grief, if I have to go through all this tube tweaking, bias setting, capacitor capin ritual, when do I get to pick? It just ain't worth it!

So I swapped for a couple D123's in my Vegas 400 and I'm pickin in thirty minutes, and it sounds great. I think I'll stay with plug and play.

Plug and play. Yep. Your still not immune. I have had peavey amps, as well as other solid state amps, back and forth to the shop--little things wear out. I had an LTD once, that had been gone through, had some upgrades, and given a good bill of health. 3 weeks later, I had a mild distortion appear(sound familiar???) One more trip back to the shop, and found a transistor that went hinckey. no, it wasn't missed, but simply decided to die. Sooooo, A new transistor, and the amp was perfect again--yes, it was back to "plug and play". Stuff happens--tube OR solid state--no one is immune. Want to discuss brand new amps out of the box that are broken, right from the factory?? Not too often, but it DOES happen. Another thread maybe.

Joel DeGarmo · Post by **Joel DeGarmo** » 22 May 2009 7:18 pm

I thought my old Fenders were plug n' play?

Bill Duncan · Post by **Bill Duncan** » 23 May 2009 5:55 am

I believe there are a lot of pickers who can just pick and not pay a lot of attention to their tone, especially when they play fast tempo songs. With slow to medium speed songs, I want my notes to sing, and sound crisp and clear, like cool spring water in the summer time, with no sign of hoarseness or "fur" around the edges. That's what I keep hearing, hoarseness and fur with tube amps, and that is absolutely intolerable to me!

Where I can really pick up on the "fur" is if I use echo, the trailing edges of the notes have fur on them with tube amps, and the echo seems to accentuate that effect. I don't hear that with my Vegas 400.

Surely I am not the only one who hears this with tube amps.

Bernie Hedges · Post by **Bernie Hedges** » 23 May 2009 7:42 am

Jim Sliff, In regards to your comment about JBL speakers not being high powered I am not under any mis-conception about the power rating. I should have been more specific about my particular case. My twin came stock from the factory with K-120 12" JBL speakers. NOT the D-120's that everyone keeps mentioning. The K-120's are rated at 100 watts continous sine wave, which in my mind is high powered. My twin is rated at 100 watts RMS. So what I have is 200 watts of speaker power in a 100 watt amp. If there is any distorion in this rig it is not coming from the speakers. The little fur or edge that Bill is concerned about could be coming from many different places as many have already pointed out.

Dave Mudgett, Your comment about NOS 6L6 tubes being essential IS a misconception. The best tubes being produced today are coming from Russia and Eastern europe. I do not believe there are any US Tube manufacturers any more. Tube companies like Groove Tube simply buy the tubes from Russia or china and pout there name on them and charge a lot more. I re-tubed my Twin with a complete set of tubes from JJ Electronics made in the Slovek Republic. These tubes come in matched pairs so biasing is almost unnecessary. They are the best sounding tubes I have ever put in an amp. Here are 2 links for reference:

http://www.jblpro.com/pub/obsolete/k_series.pdf

http://thetubestore.com/

The great thing about this forum is the knowledge available and shared by the members.

David Doggett · Post by **David Doggett** » 23 May 2009 9:00 am

Just to add to what Bernie said about JBL's, the 25 watt (RMS) rating was for full spectrum uses, which includes bass and is much more demanding. The rating was upped to 60 watts for guitar use, because it is a more limited spectrum without bass, and this was based on trial and error by increasing guitar volume until the speakers blew. Two of these are pretty safe in a Twin, but lots of distortion gets back into the full spectrum situation and can blow anything. Single JBLs in 200 watt solid-state Peaveys did blow a lot, which caused Peavey to develop the Black Widows. A single JBL in a 100-135 watt Vibrosonic is marginal. Diming that with a guitar, especially with distortion, would blow it. But clean steel with a volume pedal backed off (reserving much of the throw for sustain) is workable, if you are careful.

Bill Duncan · Post by **Bill Duncan** » 23 May 2009 9:09 am

Bernie,
I made no mistake in specifying JBL D123 speakers. The D120's, and D120F's I've tried don't sound as clean and smooth as the D123's. I've probably gone through 30 speakers in the last 6 months, and the D123's are the best sounding speakers I've found. I finally settled on 2x D123's in separate enclosures for my studio, and 2 x D123's in a single cabinet for travel. I used a 123A-1 and D123 combination for a while but settled on the 2 x D123's.

I didn't like the D130 or D130F nearly as much as the 12" D123's.

I tried Altec Lansing, but there is no comparison, JBL tops it!

Bernie Hedges · Post by **Bernie Hedges** » 23 May 2009 9:29 am

Bill, too bad the K series is obsolete but , as I said mine came from the factory stock with the K-120's. If you can find a used one with the K series I think you would like them. To my ear I like the old K series better.

Bill Duncan · Post by **Bill Duncan** » 23 May 2009 9:56 am

Bernie,
The K series is alive and well on Ebay, I've tried them. The 15's sound like the Black Widow pretty much. All of the K's I've tried sound as though there is a blanket over my amp.

For sure you can't push the JBL's I'm using hard, but I always mike my amp when I play out. I did that when I played guitar as well.

I started out in life as a Chet fanatic and it continues. Chet's tone was, and still is the epitome of tone. I think Buddy Emmons comes closer to Chet's tone than anyone, even the guitar pickers.

I know the pedal steel is a different animal, but the tone in my head is a Chet tone. I chased that for thirty years, and I love it.

Brad Sarno · Post by **Brad Sarno** » 23 May 2009 11:04 am

Bill Duncan wrote:Bernie,
I made no mistake in specifying JBL D123 speakers. The D120's, and D120F's I've tried don't sound as clean and smooth as the D123's. I've probably gone through 30 speakers in the last 6 months, and the D123's are the beat sounding I've found. I finally settled on 2x D123's in separate enclosures for my studio, and 2 x D123's in a single cabinet for travel. I used a 123A-1 and D123 combination for a while but settled on the 2 x D123's.

I didn't like the D130 or D130F nearly as much as the 12" D123's.

Bill,

I recently found myself a D123 for my smaller Tweed Deluxe type guitar amp. It's kind of a well kept secret I guess. Harvery Gerst, famous JBL design engineer swears they're his favorite guitar speaker from JBL, smoother than the 120 series. They're fairly low power though, so most steel players could blow them quite easily. But in my little guitar amp, it's really good. Full and smooth, but with an extremely clear top end, JBL style. I agree, it's quite a special speaker. It wins out over my D120 in this particular amp.

Brad

Joel DeGarmo · Post by **Joel DeGarmo** » 23 May 2009 11:36 am

Just wondering if anyone has tried using any of the EV guitar speakers? I've only heard them being used with a screaming Marshall. I do have a couple Jazz playing friends that use them too. They're heavy and somewhat expensive but they're rated for like 200-300 watts each.

James Morehead · Post by **James Morehead** » 23 May 2009 3:51 pm

Joel DeGarmo wrote:Just wondering if anyone has tried using any of the EV guitar speakers?

Oh yes indeed, the EV 15L and the EV 12L sounded real good to me, and they are very efficient. If I needed to be playing LOUD, I would shelve my jBL's and grab the EV's. For straight up tone compared to tone, my K 130's win out over the EV's and BW's to me. JBL's are my favorites.

Post by **Dave Mudgett** » 23 May 2009 7:12 pm

For a clean tone with a wide, flat frequency response and good power handling, the EVM-12L is my favorite speaker, bar none. I have a Thiele cab loaded with one that I use for pedal steel or jazz/funky-blues guitar a lot. It ain't light, but it's pretty compact.

I also am a fan of the EV SRO speaker. There are two versions - the earlier one with a white frame and orange/silver label, and a later one with a bare cast frame. I had one of the earlier ones in my blackface Deluxe Reverb for a few years when I first started playing pedal steel. I could barely play at all, but somehow the combination of my Franklin and that amp/speaker combination still sounded great if I was playing with someone at a reasonable volume that didn't bury it. Unfortunately, that rig just won't keep up volume-wise in a lot of situations for clean pedal steel.

I have another cab with a JBL K-130 - it sounds great with some guitar/amp combinations - especially my Dual Showman Reverb head. D-120's and D130's sound great sometimes also. I agree that one needs to be careful not to overpower these - they blow very easily.

I think it is important to look at all of this as a complex interconnected system, not an isolated set of components. Everything has to match up properly - player, strings, guitar, vp, connectors, effects, amp, tubes, and finally speaker(s).

Darryl Logue · Post by **Darryl Logue** » 23 May 2009 10:54 pm

Not all fender amps are created the the same. I used a 69 twin completly rebuilt with 417 Altecs Sat morning with no effects,..tone heaven. Sat. afternoon Verizon theatre backline fender reissue twin very fuzzy, not good. Then heard Junior Brown using a
fender custom 15 that I have played thru at knuckle heads saloon. He liked it better than his own amp. Tubes, speakers, bias, msc, it does make a difference.

Mike Poholsky · Post by **Mike Poholsky** » 24 May 2009 7:21 am

Here's my pocket change. Just had my 64' Blackface Twin rehabbed by Ken Fox, and I put in the 15" Eminence that came out of my Steel King when I put in the Peavy 1501-4. I've been using the Steel King for the last 3 years.
This weekend had a jam party and decided to A/B the amps so I could get an idea of the difference, in a live situation. Played the Steel King Friday night and my Twin Saturday night. It was outside not very loud, but we had drums, had the Steel King at 12:00 on both volume controls and the Twin was up to 5 mostly on 4.
Probably the best word to discribe the difference is presence. The Steel King sounds good, obviously has plenty of power, but lacks a presence that the Twin has. Probably most noteable on the higher strings and register. I know this is going to sound wierd, but the FSK doesn't sound as clear.
I was surprised that the Twin had so much more presence on the higher end. I can hear that 3rd string with a clarity I can't get out of the FSK. Even as I get up above the 12th fret, the tone & clarity are really pronounced with the Twin. They are NOT harsh, brittle highs. Yes I'll say it, I think I actually got a little more sustain out of the Twin. At least that was my perception.
There is absolutely a tonal difference between the two even at music room volumes. I prefer the tube sound, because of the presence and richness, that I can't achieve with the FSK. I did spend a lot of time reading on the Forum about settings for the FSK and got it dialed in to where I thought it sounded good. Having played the amps back to back in the exact same situation, there is a pronounced difference.
Now, this is a newly rehabbed Twin with new JJ Power Tubes, so its probably at the top of its game. I'm not hearing the fuzz, but I also haven't had it really cranked either. I am also well aware of the difference between the Peavy BW and Eminence speaker. I'm not sure if the Eminence is the speaker I'll eventually end up with, but I wanted to hear a 15" speaker in my Twin and it was the one I had. I have to say, a Blackface with a 15 in it, looks freakn' cool.
The speakers that came out of the Twin were EVM 12S and I did play those a little in the music room and they sounded great. So, I'm going to put those in a seperate cab. The weight is manageable, Twin is 71 lbs, down from 93 with the EVs. FSK is 61 lbs.
My vote: Tubes

James Morehead · Post by **James Morehead** » 24 May 2009 7:39 am

Mike, try that twin's volume at 9-10, and you will here more difference yet--in a good way. That amp will really open up and sing. I played my Vibro that Ken just did, and it was unbelievable. Volume at 9, and control it with my Volume pedal / Allen Bradley pot. K130 JBL, too. The rig is a screamer!! My Professional never sounded so good. Thanx again, Ken Fox!!

Post by **Dave Mudgett** » 24 May 2009 8:21 am

Somehow I missed this.

Dave Mudgett, Your comment about NOS 6L6 tubes being essential IS a misconception. The best tubes being produced today are coming from Russia and Eastern europe. I do not believe there are any US Tube manufacturers any more. Tube companies like Groove Tube simply buy the tubes from Russia or china and pout there name on them and charge a lot more.

I stand by my statement. You have a mistaken premise - that NOS tubes are being produced now. NOS stands for "New Old Stock", and are tubes that were produced some years ago - anywhere from the 80's on back - in US or European tube factories, but held in stock and never used. I am emphatically not talking about current Groove Tubes or anything like that.

It is my very strong opinion that nothing being produced today remotely compares to good examples of these US or European made NOS tubes - especially power tubes when the amp pushes voltages well beyond the tube's design center, like many Deluxe Reverb, Twin Reverb, Music Man, and some other amps do. The last time I listened to someone's "friendly advice" to use some "latest new and improved" Russian 6V6 power tubes in my Deluxe Reverb, two days later they failed catastrophically, taking the output transformer with them. It took me a year to find an appropriate old [edit - output, not power] transformer for that amp. I have seen similar cases. Go right ahead and use them if you like - to me it's like Russian Roulette (pun intended).

The only tubes being produced today are, essentially, being made in Russia, Eastern Europe, and China. There is a project to "make" tubes in the US, but it is my understanding that a good portion of the production - either assembly or parts fab - is being done elsewhere.

The fact that the "best" (only) current production is these offshore tubes does not change my conclusion: many vintage guitar amps - especially some of the high-power amps I like, which push the tubes pretty hard - demand good NOS power tubes. Try flipping the "Hi-Power" switch on a Music Man HD-130 amp, which puts 700 or more VDC on the plates of the 6CA7 power tubes, using a set of these imports. No thanks.

This is one reason I'm glad that there are some alternatives to using valuable old vintage tube amps with expensive NOS tubes, which was my earlier point.

BTW - I'm less concerned with preamp tubes. Some of the recent-production imported preamp tubes sound fine to me, and they're not generally having to handle beyond-design-center voltages and currents.

Of course, these are my opinions. You should use whatever tubes you like.

Brad Sarno · Post by **Brad Sarno** » 24 May 2009 8:37 am

Dave Mudgett wrote: It is my very strong opinion that nothing being produced today remotely compares to good examples of these US or European made NOS tubes - especially power tubes when the amp pushes voltages well beyond the tube's design center, like many Deluxe Reverb, Twin Reverb, Music Man, and some other amps do.

Thanks Dave. This is absolutely the case. There are some pretty impressive new tubes, but it's all relative. Even the best new stuff doesn't hold a candle to the ruggedness, reliability, and longevity of a good old US/Euro power tube from the '60s. Back then the whole build mentality came from military spec thinking and testing. Today, tubes are not critical devices, and they simply aren't built for the same reasons and with the same strict testing and assembly techniques. Over the years, I've found amps built in the '60s that still had original tubes, and were in excellent condition decades later. But now that life expectancy on tubes is 1/4 or less in general. It's the nature of what drives the vacuum tube industry. It used to be about manufacturing for the space program, military communications, professional broadcast/recording and cold war defense systems. Today it's pretty much just for guitar players and audio nuts. Not what some people consider critical applications.

For those with the $$, there are still some amazing NOS tubes out there to be had. And honestly, I myself generally save money and use the best new stuff I can find, and I've had pretty good luck. But if I did use some of these higher voltage and more high strung amplifiers more often, I'd spend the bucks and use the NOS stuff for the reason Dave explained.

Brad

Bill Duncan · Post by **Bill Duncan** » 24 May 2009 10:10 am

A note on the no tubes made in the USA. Musicians Friend is advertising Fender amps with USA made tubes. Such as the GT6L6-GE output in the '57 Twin reissue.

Post by **Dave Mudgett** » 24 May 2009 11:32 am

Bill Duncan wrote:A note on the no tubes made in the USA. Musicians Friend is advertising Fender amps with USA made tubes. Such as the GT6L6-GE output in the '57 Twin reissue.

It is my understanding, based on things I have read about them over a period of time, that these tubes are assembled in China with some of the parts (I've heard various percentages thrown around) made using the old tooling and materials from the GE plant in Owensboro, KY. If anybody has information to the contrary, I would be very interested to see it. Here are some discussions of these tubes -

Watford Valves Forum

Harmony Central Announcement back in 2002

Gear Page discussion

kcanostubes feedback

Some people like 'em, some don't. But I don't think - again based on reports I've seen - that they're "US-made" in the strict sense of the word. Two of the issues I have with new tubes are QC and vacuum strength - this is based on various reports I've read that I linked to in earlier threads on this topic. I expect that a forum search on NOS tubes with my author name will turn these up (possibly on the old forum, not certain).

The going rate for these 6L6GE's is $60/matched pair. I can still get NOS Phillips/Sylvania 6L6WGB tubes for that kind of money. No, these WBG's aren't NOS Phillips/Sylvania 7581A tubes or old RCA black-plate 6L6's ($100 apiece or more) that I'd love to have in my Dual Showman/Twin Reverb, but I have found them to be a good, workable tube in my old Fenders for the last 10-15 years.

I realize a lot of this is strictly subject to personal preference, but I don't think one should mistake any current production tubes for good examples of NOS tubes. If they work for you - great. But for me - as long as I can continue to get workable NOS tubes without completely busting the bank, I will. In addition - when a solid-state amp works for what I need, I'll save my old tube amps for another day. I didn't even bring a tube amp with me to Tennessee. VP => Tubefex => Evans FET500 works fine as far as I'm concerned, with a Pod for guitar. Travesty to a tube-o-phile? OK, I'm fine with that.

Bill Duncan · Post by **Bill Duncan** » 24 May 2009 12:53 pm

Dave,
I don't know what the actual state of US tube manufacture is, I just happened to notice the "Made in USA" statement about the tubes used in the Fender amps listed on the Musician's Friend website. To say that electron tube manufacture is not a priority in the US would be an understatement.

Mitch Druckman · Post by **Mitch Druckman** » 24 May 2009 5:30 pm

Even if tubes were to be made in the US, I doubt that the quality would ever equal that of the old RCAs and such. Back in the 50's and 60's the best tube manufacturing was tied to military specs and the abundant use of tubes in radios, TVs, and hi-fi. Today we're just talking about tubes for guitar amps.

Groove Tubes tried re-engineering the old Mullard 12AX7 a couple years ago. Designed in the US, I believe they were actually made overseas. While it was a noble attempt, most of us who tried them thought they missed their mark. There have also been attempts at remaking the RCA 6L6 and others. I just hope they keep on trying.

Joel DeGarmo · Post by **Joel DeGarmo** » 24 May 2009 6:32 pm

I feel like the the thing with tube amps in general is that for the most part each one imparts a certain character to the tone. That character ends up being somewhat unique based on tube choice,speaker choice,circuit type,transformer choice,capacitor choices,bias settings and overall amp health. The speaker thing makes it even more unique because we use "guitar" speakers. Sound reinforcement speakers at least try to be true to the original signal but guitar speakers by nature are designed to impart a certain "sound" to the situation. Just look at the frequency chart on a guitar speaker vs. a sound reinforcement speaker, it's full of mountains and valleys. Black widows in general are more of a PA type speaker so they bring less "character" to the table. To me, when you play a tube amp you choose to hear the amp just as much as the guitar, where with a typical peavey style amp you hear more of the guitar and less outside coloration. Just a thought. My favorite sounds are tube ones because I like how it flavors things.

Bill Duncan · Post by **Bill Duncan** » 24 May 2009 6:53 pm

Joel,
The JBL's were hi fi speakers. They made some for Fender, but even those were hi fi speakers with slightly opened up voice coil channels to help prevent voice coil rub. These were designated with an "F" in the number.

Joel DeGarmo · Post by **Joel DeGarmo** » 24 May 2009 8:23 pm

Is there a sound you have in your head that you haven't gotten yet? Some sound from an album you want to attain? Your ears don't lie. If tubes make your brain hurt, get rid of them. Liking what you're hearing makes playing worthwhile to me. If I don't like the sound, I'd rather stop playing for the most part. My background is 6 string guitar and I can't count the number of times I've heard people tell me how much they want a nice strat but they want to put humbuckers in it to make it sound like a les paul and my brain hurts for a second and then I knod my head and help them pick out pickups. They only want a strat because they like the idea of a strat. There's no magic frequency you're missing in your listening. In the end I feel like the question you should ask yourself is: "does it make you want to dance?" If the sound you hear doesn't do that, run away.

The Steel Guitar Forum

Tube Amplifiers

enjoying this...

EV speakers??

Re: EV speakers??

How do you put your finger on it?

Why do you have to like tube amps?