[Charles Calkins]

Anybody ever heard an "Old wives tale" that says something like "If you have a kind of laid back sound coming from a preamp and you want to brighten it up swap tubes!!!" Do tubes really make a big difference?

                                                          Cheers
                                                          Charlie

[rockadanny]

I have a Mapletree Audio 2A/SE Linestage which sounded great with the stock tubes. But after a while I was looking for a more relaxed sound. Consultation with the designer/builder (Dr. Lloyd Peppard) led me to changing the output tubes from 12SN7GTs to NOS 12SX7GTs and voila! More relaxed presentation without losing any detail. So, IME, swapping preamp tubes did make a big difference. No wives' tale, just fact.

[Brown]

Fact not wifes tale. Every tube manf. has a signature sound characteristic. A Mullard does not like a Tele or Amprex. Try and find out yourself.

[JIMV]

I have a PrimaLuna amp. It came with KT88's which was very competent in reproducing all the upper registry in comparison to the EL34's I had in my older amp. After 7 months a tube failed. In addition to replacing the bad tube, on a recommendation from Upscale Audio, I bought a set ot KT77's.Right out of the box they threw a MUCH bigger soundstage and had a liquid midrange like EL34's. I am still running those as the sound is seductive. So, I know the sound of 3 tube types in my gear. EL34, magic midrange, KT77, vast soundstage with the magic midrange. KT88, power and better definition of the upper registers. The KT88's reproduce the sound of a metal instrument like a triangle amazingly.

Yes, changing tubes to another type does have a big effect. I have also read that buying better tubes of the same sort will have an effect but I have never tried that.

[zacster]

I made an even bigger change when I went from EL34 in my Dynaco, an indirectly heated pentode, to 6B4G, a directly heated triode.  In the process though a lot was changed in the circuit out of necessity so maybe not directly comparable.  The ease of presentation just floored me the first time I heard it. 

As for direct tube swapping of different brands, my experience is that they will make a difference.  Whether it is better or worse is a different story.  My favorite experience is when I put in JJ 12AU7s into my Foreplay in place of the original 5963, then the EH 12AU7.  I put the JJs in and only once took them out to change the flavor and I put them back in after about 10 minutes.  This is swapping a modern tube with a different modern tube.  One other time I put in a used old stock 5AR4 and it was much better also in place of the Sovtek that was in there. 

The bad experience I had was when I bought a quad of SED winged C EL34s for the amp (before I went to 6B4G).  Everybody swore by these.  I put them in and could not here a difference.  It wasn't worse, but I spent money on something I didn't need.

As a KT88 replacement try the Genelex Gold Lion reissues.  They are supposed to be really nice.  I've only heard the real old thing and those are incredible.

[SkyBlue]

I'm very new to tubes, tube swapping. Don't know a triode from a pentode.  I currently have a Consonance Cyber 222 which came with quad 6SN7 electroharmonix and a  Sovtek 5AR4 rectifier. Sounds really great, but I wanted to try tube swapping, so  I got a set of matched quad sylvania Chrome Top 6SN7 GTB NOS tubes. The jury is still out. I'm not sure these two brands of 6SN7 tubes sound the same, or my hearing is just off so i can't hear a difference, or i can't remember what the 6SN7EH sounds like in the first place to make a decent comparison, or maybe it needs to burn in more.  Does anyone have any experience tube swapping in a cyber 222?  Any recommendations for other 6sn7s to try?  Tungsol ? Listen mostly to jazz vocals and interested in improving imaging.  Do tubes need to burn in? Thanks...

[jmpiwonka]

i understand tubes will need to burn in.
swapping from SV83 to El84 (output) tubes in my amp made a difference. sv83 smooth, great imaging, very 3dimensional sounding while the EL84 have more juice, not so quick to clip, seem a little warmer, image a little worse and not quite so 3d...i still think i like them better though.

[twitch54]

FWIW, to all the 'newbie' tube swappers out there.....keep in mind that frequent tube swapping depending on quality of ones tube sockets can in time lead to less than ideal 'mechanical connections' not to mention a sizeable drain on ones pocketbook. I actually meet a young lad at RMAF last month who admitted getting sucked into tube rolling to the point that in less than one year he spent more on tubes than the amp he was rolling them in to !!

[Frihed91]

Doc's preamp also takes 6SN7s, some of which can be very relaxed sounding: like Raytheon type 1 (no extra support rods), or the RCA grey glass VT-231s, or almost any early Sylvania, except for the 6SN7W.  However, these tubes are costly and maybe not as good as sme of the 12 volt models.  I am not up n 12SN7s, unfortuntely. 

[jmpiwonka]

i swapped the driver tubes in my amp.
took the mullard 12au7 out and put in a telefunken 12au7. listened a bit and decided it didn't make much difference once i got through a bunch of cds over about a weeks period i was thinking my bass extension and output weakened a bit.

put the mullard back in and yep, back came the bass.
i think the telefunken mids were a bit smoother though.

it does make a difference, just depends on the music and the system as a whole though. what works for me might not work for someone else.

[jbtrio]

The more resolving your set-up gets the easier and bigger the differences will be heard.

Tubes do make a difference and you can tailor the sound to your liking.

Saves me from changing equipment as often.

Joe

[JIMV]

i understand tubes will need to burn in.
swapping from SV83 to El84 (output) tubes in my amp made a difference. sv83 smooth, great imaging, very 3dimensional sounding while the EL84 have more juice, not so quick to clip, seem a little warmer, image a little worse and not quite so 3d...i still think i like them better though.

It took over 50 hours for my KT88's to lose their hard edge but worth the wait.

[Bob in St. Louis]

How does a potential tube roller know what tubes are acceptable to roll in?
Obviously, any brand 12AX7 or EL34 tube would "fit in the hole" where another 12AX7 or EL34 came out, but where would a fellow go to find what else would work?
And, most importantly, how would one know what to expect regarding changes in sounds quality BEFORE purchasing a set of tubes?

Hmm..... I watch movies from NetFlix. When I send one back they send me another one and the cycle repeats.
Wouldn't it be neat if there was a "NetTube".   aa

Bob

[Niteshade]

The best way to know what to expect while tube swapping/rolling is to ask the maker of the tube amp. It all depends on the circuit. Some circuits are sensitive to different tubes and brands while others are not.

[jules]

How does a potential tube roller know what tubes are acceptable to roll in?

Bob,

I've rolled an alarming  number of NOS 6992 [and closely related] valves in my AKSA GK-1. While I agree with Niteshade, I also believe that different manufacturers approached their design with varying goals. I'd guess that German tube desgners like Telefunken and Siemens had precision and accuracy uppermost in their minds, while working with or encouragong the natural tube type qualities were probably lower on their scale of prioroties. At the opposite end of the scale,  Amperex [ and famously the early Amperex D getters] valves are unashamedly proud of their tube qualities. I'd guess that while Amperex certainly wanted accuracy, they took account of the "sound" of their valves and worked with it, rather than trying to eliminate it. Mullards made in England, have the sort of slightly warm and perhaps less detail obsessed sound, that is characteristic of other English audio products. The downside can be that, in the wrong place, some "warm" valves tend to shout excessive tubiness at you while "clinical" valves can seem insipid in low detail sensitive systems 

One of the great things abut valves in a pre-amp, is that they allow for definable changes to match other upgrades to a system. A colourful tube might be a better choice with a system lacking detail, while a precise tube might fit in better with an accurate system [perhaps counter to what you'd expect] .

jules