The Tube Swapping Thread

dears,

ordered my 2nd 5157 tube to make the preamp as: V1, v2, V3 = JJ5751, JJ5751,JJ83s or V3=JJ803s...
Should receive it today for tests ...!

Ignantios wrote:....That's all.Nothing more

Yes of course, I see your point Ignantios, I am aware that it was a LOT more info than you wanted.  Sorry if it seemed to suggest you don't know anything about it, that wasn't my assumption.  Well I would only say, please keep in mind you're not the only one who reads these threads.  People come here from other areas to just browse looking for help and some of them have very little if any experience of this stuff.  I know because I send them here from other Facebook pages, for example, when they request info like this for their H&K gear.  Perhaps they may benefit from seeing something written down which guides them as beginners? This info will be available on the internet long after you and I have stopped posting on the site.

I always think that we're primarily an info and advice site not a "swap a textspeak comment" after all, although it's nice to do that just for the human touch occasionally.  We now have the "Anything else that needs to be talked about" area for that.  It takes me only a couple of minutes as a fast typist to type a long post like that and it's time I'm prepared to give if it helps somebody.  It takes you only a few seconds to scan it ignoring any sections which are irrelevant to you, (the whole thing if need be ).  And it just might sort out somebody else's problem at some time.  I reckon it's worth it, don't you?

Hope that choice of another 5751 turns out to be what you're looking for TRB. I'll be interested to hear your opinion on the pair together, everyone knows I love 'em but I don't do really high gain stuff. Bon chance!

They are definitely a HiFi audio company first. They make their own speakers and amplifiers as well (and they are stunning). I`m not even sure how it came to be, but they are actually partnered up with H&K now, however.

When a piece of metal (the filament, in this case) is cast, it`s straight and has certain molecular alignment. When it`s bent (made into a curly bit to go in the tube), that natural alignment changes, and you have inconsistent natural tendencies for it. Their process Cryofreezes the tubes, which is supposed to re-normalize their molecular alignment, and it makes the innards think their new shape is how they were born. Supposedly it allows for nearly indefinite lifespan,barring abuse and utter neglect.

Is it all legit? maybe so. Would I encourage the average musician to put them in a beater rig just for kicks? Nope. It`s not enough of a difference, and the subtleties will get eaten up in the PA anyway.

I would have never willingly chosen to use these tubes over a brand like JJ`s, simply because they are *very* expensive. I just happened to be at the right place at the right time and the opportunity to get my hands on some at a more affordable price fell in my lap, so I took it. If I had to load my second GM with new tubes at full price, it`d be JJ`s in a heartbeat. But if I were a person who just had a pile of dough sitting around to spend without consequence, I`d not use anything but Wathen.

Love it when someone else's opinion confirms your own.  My first thought was "well all of that will be lost with the movement to micing up the amp and shoving it out through the uncryogenically powered PA!  Now for recording studio work...  Ok, that's another story.

Yes, the hifi world has this sort of thing embedded in there and it is relevant to that field.  People are prepared to part with silly amounts of money for diminshing returns gear which they have no facilities to get the best out of anyway!  The gullibility factor is always high.  It's easy to design and build an amp that shows <0.005% distortion nowadays.  (It would sound crap with a guitar through it of course but that's the sort of level you need to give that empty soundstage I was burbling about!)  But I'm not at all convinced about the audibility of this sort of thing in a live band context!  Any subtlety of sound would be swamped by other factors.  So, would most people be thinking that it's worth spending out a ransom for you to drool over your tone while you're noodling in your house?  I can't see the sense but that's just me.  (Hence the point about convincing yourself to not buy upwards unnecessarily in the above post.)

If I am linking it into the correct area the theory is sound I think.  Again it's an area which I have a dangeroous amount of understanding in, (and that means dangerously low).  They have used cryogenic treatment of steel to increase hardness for a long time now but, as I understand it, it is at the expense of toughness.  Brittleness creeps in and must be balanced.  Just as you said, the atoms originally start off packed in a basic lattice and get rearranged into a more coherent one (Austenite -> Martensite).  It does improve the hardness but I'm not convinced that that is really too relevant in a valve?  The cathode structure is only the former that the surface oxide coating is mounted on.  It's the coating that emits the electrons and most valves die by the contamination of that oxide coating not by falling apart.  I don't know if they are treated with the coating on or before, and if so whether the coating itself is restructured in any way.  And there is one thing that puzzles me.  The conversion back the other way is effected by - guess what - heating!  Now what is it do we do with a valve?  I wonder if we have someone on the site who has a better understanding of this than me?  It would be good to have someone explain why it is successful, (or not).

Anyway, as you said it was an opportunity for you and one which I would most likely have taken too if I could afford it at the time.  My curiosity gets the better of me I'm afraid.  I'm sure you do the same bit of maths as me when something like this is pitched to you by a marketing agent, divide what he tells me by four, take away the amount of gullibility he reckons I am showing, that is the maximum value of the amount of truth in what he says.  And you report that you CAN hear a difference which is the bottom line.  The H&K thing is making my nose twitch.  I smell an "audiophile quality version" of the GM36 coming out at "silly money" prices.  (But then I'm a died in the wool cynic as you know!  )

Ya know, I might just do another A/B demo like the last one but this time I`ll do JJ`s vs Wathen. The new amp should be here today. It`s really just a matter of copying the preset library to the new one so the settings are literally identical and letting it rip.

Now that would be cryogenically cool Jeff. I'd like to hear that, although it is possible that the differences wouldn't come across the digital interface if they are very subtle. Anyway, get it done and we'll see, we're waiting with bated breath!

HI all

not yet receive my 2nd JJ5751. may be today... for now V2=12AT7 NOS.

In the mean time I tested the V3 across JJ 83s, JJ803s, and TungSOl 12AX7 GoldPin.
Well I found the 803s to be the most agressive and prefer the rounder 83s and the TSGold. And between these 2, I give a longer try to the TS Gold, as I found it gives me :
- less microphony,
- as warmth as the 83s,
-  a tad more clarity...
All these things are subtle but noticiable enought to make a "feeling"....

will keep you in the loop when testing with the 2nd 5751.

Dears

just instaled my 2nd 5751 tube.

Well very nice tone, I ended up with:
V1, V2, V3 = JJ5751, JJ5751,JJ83s.

I previously tested the TS Gold in V3, and it was nice with a 12AT7 in V2, but with the 5751 in V2, the TS Gold was still clear but more on the clinical side with the 5751 additional gain vs the 12AT7... if makes sense...
So I put back the JJ83s in V3, and a bit less "clarity" but more warmth, what I was after... So I closed up my GM36 and go now for this set up !

In another thread I mentionned the usage of a Buffer: I'm testing different Aop from Burr Brown and TI. As I said, the buffer adds a bit of "creamy tone/less harshness" (subtle, used with mys Axe FX II and the GM36). With these tests I'll try with a friend to improve this buffer "effect" (even if a buffer should not have any effect !), but it's a nice addition.

I think you might mean a clean boost buffer immediately before the GM36?  If that's right it's strange as I strongly suspect the GM already has a SS buffer built into it!  There will be crying and gnashing of teeth over this news, I've seen it elsewhere, but it doesn't alter how the amp sounds to you, you already like it or loathe it so why should the technology make any difference.  I just view it as another offering in the line of onboard effects, a built in overdrive unit just like most of the SS detractors put into their chain anyway and a better one than any of the scratched and battered noisy worn out "vintage" pedals most people seem to want to pay a fortune for!

In at least one other amp in the TM/GM range I know there is one based on a MC33087 dual opamp, (one amp of this is not in use for anything), with +-15V lines.  That's a general purpose offering as it makes no difference to guitar circuitry providing the opamp is not used to generate the distortion internally in any way.  If the signal is within bandwidth limits and below the power lines as it is here, the amp just passes it through like sweetcorn.  I have a wonderfully robust opamp comparison report by Samuel Groner which makes for interesting reading.  He tried to update and improve on Walt Jung's work in this field.  If anyone would like a copy you can download it here:  Operational Amplifier Distortion - Samuel Groner.  It doesn't include those Burr Brown "mega well good" types but it does have equivalents and also humble TLO71/2/4 types, and if the Burr Browns are even better then the result is a no-brainer.  Guess what they show....  It's a dry read but if you jump to the final "Some Personal Conclusions" section and just read a couple of paragraphs it's there.  It proves once and for all that when you use even a simple TLO71 with sensible bandwidth and voltage level signals, high enough power lines and you don't load it incorrectly, all of which things are taken care of in the H&Ks, the distortion it generates is below the level the best quality instrumentation can measure!  That's kind of 150-170dB below the signal level.  That's - err - 0.000000032%.  Must have ears like Yoda to hear that!

The answer to all of this and whether or not you can really hear any differences is Blind Listening Tests which you and your friend could try out if you set it up correctly.  You need to put your buffer in circuit in a way in which it can be switched in and out by an uninvolved party depending on the toss of a coin.  The change must be immediate and undetectable so you don't know whether it is in or not at any time!  An easy way is to have the boost pedal out of your sight behind you being switched in and out by your friend who can also click a second pedal sometimes in a way that prevents you from guessing whether it has changed or not.  Then you play any way you want and make up your mind whether you think it's in or not.  Your friend records a list of when the boost was in or out and you record your guess, and neither of you knows what the other has put until after the entire number of tests has been run.  After each one, your friend tosses the coin again out of your sight and the boost is reset with the dummy pedal clicked to confuse you as to whether the boost is there.  It is essential that you do not know whether it is in circuit or not and he does not know whether you guessed right or not and every step must be taken to ensure that.  Finally, after a lot of tests, your results are analysed statistically to see whether there is anything significant.  Doing it 4 or 5 times is not enough, 50 or 100 tests would be, the more the better.  You need the statistical analysis because it isn't enough to just get more correct guesses, that could happen by chance.  For example 55 times correct out of 100 would not be really significant unless it occurred repeatedly!  You need to calculate a "level of significance" out of the results which means how likely that result is to be an indicator you can hear something or not.  The more times you do this the more accurate the results get, but it depends on the secrecy aspect to be of any use at all.  Just changing the setup and listening is definitely NOT a way to show there is a genuine difference in anything but the most obvious of cases, like whether your Rat distortion pedal was on or not.    Once you are set up it's actually very interesting to do!  And it also depends on whether you are trying to find out IF you can hear a difference or you are proving you CAN hear a difference.

Ok, the H&K opamp acts as a constantly in circuit clean buffer in most situations and an assymetrical clipping overdrive with a high enough signal.  When it's calm it has a gain of about 3x, then when the Boost is kicked in it ups its gain to about 7.5x.  The clipping kicks in at about 6.5V and 12V on opposite sides of the output signal.  I should also point out that there are two back to back 2.7V zeners across the input too which will protect input capability to about 3V.

Glad to hear about the 5751s. That's a more difficult one to test rigourously but it should be based on less subtle changes than the opamp issue so probably is fine with just a listening comparison, at least I was prepared to admit so with my own swapping.

Hi,

this is just a simple buffer w/o any boost fx required.
A friend of mine build a very nice/transparent buffer on a standard scheme (Super Buffer AMZ), initialy to be used with my Axe FX rack.
Beyond the regular for a buffer which is to keep a signal "quality" with long cable / complex pedal board, it appears the buffer helps to tame highs harschness, providing a more creamy tone (subtle effect).

And with the GM36 it makes some good thinks on the tone I'm seaking for.
That's all.
And comparing some different AOP give some subtle but real differences. And I really like to test all these stuff !!

...it appears the buffer helps to tame highs harshness, providing a more creamy tone (subtle effect).

I do not doubt your word that that effect is there, but if that's the case then I'm afraid you cannot describe it as a transparent buffer!  If it were transparent it would make no difference whatsoever by definition and it would pass through the harshness along with the rest of the signal.  That's the bit that everyone misses.  What you have is a mild tone shaping buffer which you feel improves the tonal quality!  If something is removed a change has been made and the description "transparent" cannot apply.  And I have no doubt at all it improves things for you, I agree with you 100% on that, but transparent it just isn't because it makes a tonal difference.  We're in complete agreement as to the benefits but we must be careful of how we describe things so they stay accurate and truthful.  There may be others reading what we write who don't understand as much and who will go on and quote it in an even more skewed way.  Then another myth is born....    (there I go again).  And these things are important if we are to improve the state of the field we love so much so that even better equipment can be built in the future.

Jack Orman's work is well known and is pretty good.  He does things by well established standard methods and gets the best out of them within that.  I couldn't fault his simple design there, paralleling the 4 opamps in the single package is a sensible way to go.  I predict there will be much arguing about which is the "right" opamp to use here and they miss the point.  If the opamp is sufficiently low noise, and there are cheap alternatives to exotic Burr-Brown types which are just as good, it will make no audible difference in any way.  This is a flat response x1 buffer designed to work within the opamps' capabilities in every way.  Remember the 150-170dB down I quoted?  Could you hear that?

I also use a buffer system which I designed and built myself too.  I don't like wireless!  It's more of a reliability thing than anything tone related, so I use a 15m cable.  I wanted to have the benefit of that long cable and not be tied within 3m of another box, so I opted for a head amp in the cable approach.  As you know it requires a low impedance output buffer to drive that length of cable to prevent consequences from the cable capacitance etc.  My system has a remotely powered tiny amp built into a piece of copper shielding tube about 18inches from the guitar plug.  It feeds into a box back at the amplifier which is a true x1 buffer.  I chose to implement no gain and no tone adjustment other than the benefit of loading the guitar with a purely resistive load to remove the top end droop caused by the cable length.  I make sure that anything above the audio band is removed as this has no audible impact on the signal but prevents other forms of distortion from creeping in.  It's different to everyone else's that I could find, mainly because it is no compromise, not being built to a production budget.

All of the similar systems I have seen have a single JFET head amp, I honestly feel that's poor and a bad compromise!  I chose to use a JFET + a BJT pair which improves my control over the design factors immensely.  Amongst other things it allows me to have a +-3V signal level before clipping within the head amp.  You can't get anything like that with a single standard JFET.  This drives the signal down the line as a current not a voltage.  The receiving amp is unique in the way it phantom powers the head amp.  It supplies it up the same wire as the signal returns but remember the signal is a current.  I can use standard guitar cable and it no longer needs to be an expensive type.  The box houses a 5 transistor amp, (plus another 3 for its voltage regulator).  The way I wanted to implement this is, as I said, unique.  It could not be done using opamps, the circuit configuration could only be implemented with discrete transistors.  My idea is that if I want any tonal balancing to be done I can do that once the signal is at the amp at a much lower impedance.  Isolate the two jobs.  Suppose I have a guitar which likes to see a 1M5 load and and one which likes 500k+100pF, how does my system cope with that?  It can only do so by being neutral and making the adjustments outside it.  If I want to adjust the loading on the guitar for some reason, say increasing the capacitance across it or generally lowering the load impedance, it can be done within the jack plug directly at the guitar end, or in my case by adding in an additional tiny module to the cable as it already has socketed heads to cope with angled or straight jacks for my different guitars.  I also use an OnStage Grip Clip so the cabling is made to fit in with that conveniently.

I have been told that the approach should be noisy but there is absolutely none in direct comparison with a standard 3m cable, if anything it is quieter as the cable noise voltage pickup has been eliminated by the current drive approach.  It allows me true freeedom to move around anywhere I want within 15m and even more with an extension if it were ever needed.  And I have been told that it won't give any tonal benefit but that misses the point.  It does the job of a true buffer, it gets the signal where you want it without any change to its nature!  I really think that's what you should be fighting for in a buffer, no difference at all.  Make any adjustments in their own place and keep your system so you can easily match anything you want to put into it or any amp it is attached to.

well the original AMT z super buffer is transparent... but what I expect to do with, is actually not transparent !! I agree !
I aim to use it more like a pedal filter, in fact, to help getting the tone I like with my GM36 (very nice with the pre tube combo I installed and the ring foam in the cab)

bordonbert wrote:

Ignantios wrote:....That's all.Nothing more

Yes of course, I see your point Ignantios, I am aware that it was a LOT more info than you wanted.  Sorry if it seemed to suggest you don't know anything about it, that wasn't my assumption.  Well I would only say, please keep in mind you're not the only one who reads these threads.  People come here from other areas to just browse looking for help and some of them have very little if any experience of this stuff.  I know because I send them here from other Facebook pages, for example, when they request info like this for their H&K gear.  Perhaps they may benefit from seeing something written down which guides them as beginners? This info will be available on the internet long after you and I have stopped posting on the site.

I always think that we're primarily an info and advice site not a "swap a textspeak comment" after all, although it's nice to do that just for the human touch occasionally.  We now have the "Anything else that needs to be talked about" area for that.  It takes me only a couple of minutes as a fast typist to type a long post like that and it's time I'm prepared to give if it helps somebody.  It takes you only a few seconds to scan it ignoring any sections which are irrelevant to you, (the whole thing if need be ).  And it just might sort out somebody else's problem at some time.  I reckon it's worth it, don't you?

no hard feelings mate....got your point!

incidentally, I just ordered a set of JJ high performance 12AX7s. They`re easy enough to find, and priced at a point that makes it easy to have a backup set (even as an endorsing artist the Wathen tubes are prohibitively expensive). Almost went with the gold pin high performance but opted out at the last minute. It`ll all be a part of my dual GM36 demo video

I have always said that I would not endorse a product and stand behind something I didn`t personally believe was the best for the environment it was being used in. My High Performance JJ 12AX7`s came in today, and truth be told, they sound far better than the brand I currently use, at least at the first run through. And given that the average Joe can get an entire set of JJ`s for what one of the other tubes cost, I just don`t see it. The difference between the other brand and stock was certainly pleasant, but very, very subtle. The difference between JJ`s and the high end tubes is stark. The JJ`s are FAR warmer. Literally had to readjust the EQ because it was too flat (yep, actually had to ADD in some treble). The difference in the clean channel was stunning.

If you`re on the fence about tubes, I just compared the $13 JJ`s to a high end brand that runs about $100 a tube, and the JJ`s totally held their own the more expensive tubes. OF course that is to MY taste, with THIS amp. But given the reason we`re all here is that we own the same amp, and I like to believe my opinion is neutrally biased, I consider it a valid perspective. I`ll do a detailed demo video over the weekend so you guys can hear for yourselves.

Oh Joy Unbounded!    Even I was getting sick of listening to me go on but now I feel like a lot of the crap I've been spouting for months has been independently justified! You're an honest man Jeff and I thought I'd never come across another one other than myself in my lifetime.  If this doesn't stoke up some interesting positive debate here I don't know what will.  Come on guys let's have your responses to this new info.  

Here's where I've bought my JJ tubes (for multiple brands of amps) for many years: www.eurotubes.com Fantastic service.

I'm currently running the standard JJ set in my GM. There's also the "gold pin" set which I'm wondering is the same as Jeff's 'high performance' set? Any idea? Check this link: http://www.eurotubes.com/store/pc/viewCategories.asp?idCategory=606

The GM's stock tubes are currently acting as my spares. But I'm thinking about buying another set of JJ's... I'd love to try the 'high performance' ones.

gravydb wrote:Here's where I've bought my JJ tubes (for multiple brands of amps) for many years: www.eurotubes.com    Fantastic service.

I'm currently running the standard JJ set in my GM. There's also the "gold pin" set which I'm wondering is the same as Jeff's 'high performance' set? Any idea? Check this link: http://www.eurotubes.com/store/pc/viewCategories.asp?idCategory=606

The GM's stock tubes are currently acting as my spares. But I'm thinking about buying another set of JJ's... I'd love to try the 'high performance' ones.

The gold pins are not the same as the HP. In fact, there`s a gold pin option FOR the HP`s!!!! The HP`s have a different plate construction. I picked them as they were rated warmer than the standard gold pin offering. I ran the regular gold pins in another amp and they were great, but we`re talking two completely different animals here.

And yes, I COMPLETELY support the guys at eurotubes. They know their stuff and are very generous with sharing their knowledge and experience. I have to trim as many pennies as I can so I got my tubes at tube depot ($10 for the regulars, $13 for the HP. Even the EL84 power tubes are $10), but I have steered many people toward Eurotubes.

Ah ok. Thanks Jeff.

Can anyone post a link to those High Performance valves?  I've been across the Eurotubes site and can't find any mention of them.  I have the Standard, Gold Pin, Long Plate (ECC803S) and its gold pin, and a 12AX7MG and its gold pin.  There are full GM36 sets but these are listed as Standard, Gold Pin, High Gain, SRV and ECC803S.

Could it be the new MG version?  They say:

Eurotubes marketing wrote:A first look at another new tube from JJ! Over the last few months we have been testing yet another new tube from the good people at JJ Electronic. The JJ ECC83 MG is a “Mid Gain” 12AX7 type tube. It utilizes a medium length ribbed plate design that is much like the old Amperex and Brimar European designs. It retains all of the definition and detail that the ECC83S short plate and the ECC803S long plate tubes have but it has slightly less gain than the ECC83S but a bit more gain than the ECC803S.

Sonically it’s nice and thick sounding with a good edge that’s not brittle. It has plenty of definition even when used in an amp with lots of gain and the microphonics are very low. The ECC83 MG is a little more polite than the ECC83S which is pretty aggressive. The ECC83 MG has a fair amount of harmonic density but remains very open sounding whether played clean or overdriven. All in all it’s a really nice sounding tube and we will have the first production run in late December!

Any help?




EDIT: Aha! Just been on to Tube Depot and they list the ECC803S as a High Performance version. Is that the one Jeff?

yep. The ECC803s is frequently cross referenced with/as a 12AX7. Same pinout, same plate design. the HP has a big, beefy plate.

anyone experience with Tube Amp Doctor EL84-Cz  tubes?? The are described as follow:

The TAD EL84-CZ is the muscle man and roughneck among the EL84 models. It gives most amps
an extra powerful bass response. Be careful with amps that do already have a fat bass and make
sure their speaker can handle the increased bottom end as it might become too much. The EL84-Cz
is the most powerful EL84 tube we have ever heard. Big tone and very dynamic. Our recommendation, if a
powerful tone is what you are looking for.
d= 22,5mm

So far i replaced the  V1 for a TAD 12AY7/6072A Highgrade and the V2 with  a TAD 12AT7/ECC81 the V3 has still the Chinese 12AX7 stock tube in it, the Chinese EL84 are also still in..
At this moment playing over a cab with 1 G12-V30 vintage and one G12T-75..

Sounds good! all the "harshness" is gone and its more like a vintage rock sound ..
Tomorrow my two 16Ohm greenbacks will arrive and gonna swap them for the other one's..
Im thinking to swap the EL84 for the TAD Cz or TAD STR.. not sure yet  To get a little "metal" back but hoping for a bit "creamer" sound in comparison with the stock tubes..

EDIT:
Swapped the pre amp tubes: V1: TAD 12AY7/6072A high grade, V2: TAD 12AT7/ECC81 high grade, V3:12AY7/6072A High grade
amp: QUAD matched EL84-STR

Speakers: 1 x G12T-75 and 1x GreenBack (both 8 ohm).. other Greenback is in back order.. bit sound oky to me at the moment so don't know if I'm gonna put that one in..

Sounds (to me ) great!! much more defined, the "harshness" is gone.. but also the more metal sound.. this was where i was aiming at so for me that's fine

This evening my first play with it with the rest of the band.. so very anxious how its sounds!

Did a guest spot the other night, bit of classic rock, Free, Bad Co, Lizzy

Went through a single Marshall 1912. Soak on 18 watts. JJ el84s but 3 Groove Tube 12ax7's I used the use in my Mark iii Boogie, which I knew don't break up quickly.

Now that was the best I've heard this amp. Used the PRS Marsden with and SD Custom Custom in the bridge and Jazz in the neck

All tone controls, volumes and gains on 12 o'clock. Master at 1.00 o'clock.

Very nice, big fat crunchy warm sound and singing leads

After much reading - primarily on here - I've just ordered my JJ revalve kit from Eurotubes even though I'm in the UK.

Valves are a new mystery for me and I've decided to go with Eurotubes as some of you on here have had good experiences.

Fingers crossed mine is the same!