Will changing tube in preamp make a difference?

[KCKC]

Hey guys,

originally had this posted in "burnt fingers" no response. Thought I'd try here. Hope some folks here might be able to help me out as electronics is not my forte ...I use an ART project series preamp for my vox/guits while recording direct to PC.

http://pro-audio.musiciansfriend.com...amp?sku=180643


Will changing the the stock tube to a Ruby tubes

http://accessories.musiciansfriend.c...ube?sku=212034

make much of a difference? I want to get a real clean/warm sound even when I'm pushing 10 on my preamp gain knob.

I've heard info that's come down on both sides of the fence: will help a lot and wont' really make a difference. Anybody have any insight?

And Mud - I'm not going to buy a "brick"! This is the "Pennycaster Project" I'm rolling my coins to record!

Hope you can help! Thanks

KC

[PeteMac]

Changing a "stock" tube to one of better quality will change the sound of your pre-amp. (After all, it's the tube that is amplifying the signal getting to the output stage).
However, whether it's very noticeable or not . . .
May also depend on your mic and other gear.
What type of tube is the original?
What mic/s are you using?
Are you mic'ing a guitar amp, or playing direct into the pre ?

[morroben]

I don't know a whole lot about these things, but I changed the 12AX7 in my Behringer mic preamp and it made a huge difference. I just put in a Groovetube (nothing fancy) but it was drastically better than the Behringer tube that it came with. It actually made it a usable preamp...I was on the verge of throwing it out before the tube change.

[Guitar_Ninja]

I bought a cheap Behringer preamp a few years ago that was very noisy and hissy. I swapped out the Behringer-branded tube for a EHX and later a Tung Sol RI tube. They both helped smooth out the sound and quiet the effect.

Still useless for recording though.

[T Prior]

the answer is yes, as long as you are not trying to change the characteristics of the initial design. IF the design was for a 12AX7, then by all means , the best 12AX7 tube would bring the unit to the top of the spec chart, and , as we see above, a crappy 12Ax7 would maintain poor performance.

Now, if you are trying to change things such as headroom or gain , beyond the initial design, the answer is no. Can you get some mild changes ? Sure maybe, but generally no. As an old tube schooled electronics guy one of the first things you learn is that tube circuit designers selected a tube and designed there circuits around that tubes requirements.

A few years back I was playing thru a 40 watt Hot Rod Deluxe, it didn't have enough clarity for Steel Guitar, it broke up to early. I probably had one of every top brand 12ax7 , family relatives and 6L6's in the parts box and swapped them to death. Some things did change, tone, , some gain went down,some were tinny sounding all that, but the headroom pretty much stayed the same. I did fix the problem though, I got rid of the HR Deluxe and got a 60 Watt HR Deville !

If indeed you a have tube preamp you should have the best tube plugged in, or at least a good one !

My ART preamp has a Fender ( sovtek) 12ax7 on both sides, it works fine, or at least I think it does..

t

[jefrs]

I don't know the ART and the link appears broken... Some of these preamps use the valve in starved plate mode to emulate a proper valve amp, my AD30VT does this and does it quite well. But changing the tube for a better one serves little benefit as it is not being used as a true amplifier. If it is a true analogue preamplifier then it pays to experiment with different tubes to find the one that suits you, it may well not be the finest NOS that money can buy.

[KCKC]

Thanks for the replies guys! Fixed the links. Sorry bout that. I guess the question is: Is the ART tube preamp a "starve plate" design?

Re: other gear, as mentioned, it's the "Pennycaster Project"! I have a cheap nady condenser

http://pro-audio.musiciansfriend.com...one?sku=277522

A behringer usb interface

http://pro-audio.musiciansfriend.com...ace?sku=702540

into a PC I got at the dump running Kristal DAW.

KC

[woodman]

AFAIK, the ARTs are indeed starved-plate. i never changed the tube in mine so don't know how much difference it would make. i do intend to swap out the tubes in my Brick once i get time — i read in several online sources that it can make a big difference (being a Groove Tubes product, naturally it has Groove Tubes in it; their quality can vary).

[T Prior]

ah ha, yes starved plate like Woody mentions. The only real difference that can happen is when you change from a crappy tube to a good one, or as Gordon Ramsey would say, one that belongs in the bin rather than a good one. ART preamps are cheap and about as minimally functionally as you can get and still legally be called a tube preamp. The evidence is that they have a red LED near the tube to make sure we know, or at least we think we know it actually has a tube in it ! It glows RED, it's gotta be good !

But all that being said, I kinda like mine, it's a dual channel and has the voicing selector switch that does change the EQ characteristics. For $99 bucks I'm happy.

T

[woodman]

mine's a 1999-2000 model, no bells, no whistles, just the ART basics. i used it a lot with my Tascam 8-track cassette rig ... often got good results by punching the +20 dB button and driving the snot out of it. i haven't tried that on a DAW, so i dunno how it'd work in a digital environment. worth a try if you get in an experimental mood. same goes for rolling tubes (better ones — i'd try some less-pricey NOS like GE).

in a post a while back, i opined that an ART is better than nothing, and if you find a way to make it work for you, it surely is. and like Tony says, there's only $99 at stake. KC, you don't mention your recording rig, but i wondered if you were running it into a mike/guitar input or into a line-level input. it can get messy if you don't run it line-in.

[mudbean]

Originally Posted by woodman

AFAIK, the ARTs are indeed starved-plate. i never changed the tube in mine so don't know how much difference it would make. i do intend to swap out the tubes in my Brick once i get time — i read in several online sources that it can make a big difference (being a Groove Tubes product, naturally it has Groove Tubes in it; their quality can vary).

Woody, if you're gonna go for the tube roll, try an Electro Harmonix Gold ... better yet, if you have an old Mom & Pop electronics store nearby see if they have any old stock laying around, like an old RCA.

My tube guys tell me the Mullards you see online are mostly fakes these days, unfortunately.

mud

[jefrs]

Rule-of-thumb - Mullards only ever shipped in Mullard boxes, even military ones. So if they're in white boxes then they were probably rejects and many of their rejects got rebadged as other makes. I think we are at the end of the genuine good NOS Mullards now and we shall not see their like again.

[Dan German]

Originally Posted by mudbean

My tube guys tell me the Mullards you see online are mostly fakes these days, unfortunately.

mud

Originally Posted by jefrs

Rule-of-thumb - Mullards only ever shipped in Mullard boxes, even military ones. So if they're in white boxes then they were probably rejects and many of their rejects got rebadged as other makes.

That said, I recently bought a "NOS Mullard" 12AT7. It came in the aforementioned white box, and the tube itself is labeled "Mullard/made in Great Britain" (yeah, I know you can screen anything you want on a tube.) Whatever it is, it's better than my EH or UOS GE 12AT7. Wasn't particularly pricey, either. I'd buy another.

[woodman]

Originally Posted by mudbean

Woody, if you're gonna go for the tube roll, try an Electro Harmonix Gold ... better yet, if you have an old Mom & Pop electronics store nearby see if they have any old stock laying around, like an old RCA.

i've got a pretty good stash of NOS ... my amp tech (a tube purist — won't work on solid-state) finds 'em at ham radio shows and sells 'em to me cheap. i'll be rolling as soon as i get out from under this band demo and get some breathing room.

[KCKC]

Originally Posted by woodman

... KC, you don't mention your recording rig, but i wondered if you were running it into a mike/guitar input or into a line-level input. it can get messy if you don't run it line-in.

Woody I'm running my ric 4001 or my squier 51 or my cheap nady condenser mic -> art tube pre -> behringer usb interface -> PC usb -> Kristal (limited to 16 tracks, freeware DAW.)

is USB was the way to go?

I've been able to track songs with this set up - which is my goal - but nothing close to the quality of what some of you guys have posted.

Thanks,

KC

[woodman]

Originally Posted by KCKC

is USB was the way to go?

USB onto your system/app drive will only get you so far ... as your ambitions increase, you'll run into trouble. at some point, you might think about getting a Firewire drive to record on. a 200 GB one is only about $100.

[mudbean]

Originally Posted by Dan German

That said, I recently bought a "NOS Mullard" 12AT7. It came in the aforementioned white box, and the tube itself is labeled "Mullard/made in Great Britain" (yeah, I know you can screen anything you want on a tube.) Whatever it is, it's better than my EH or UOS GE 12AT7. Wasn't particularly pricey, either. I'd buy another.

Bottom line - whatever works.

Originally Posted by woodman

i've got a pretty good stash of NOS ... my amp tech (a tube purist — won't work on solid-state) finds 'em at ham radio shows and sells 'em to me cheap. i'll be rolling as soon as i get out from under this band demo and get some breathing room.

Sweet, that's the way to do it - a buddy of mine once found a nice stash of Telefunken 12AX7's (!!!) in an old medical unit. He won't let 'em go for anything, the bastamidge.

mud

[tboy]

Originally Posted by T Prior

ah ha, yes starved plate like Woody mentions. The only real difference that can happen is when you change from a crappy tube to a good one, or as Gordon Ramsey would say, one that belongs in the bin rather than a good one. ART preamps are cheap and about as minimally functionally as you can get and still legally be called a tube preamp. The evidence is that they have a red LED near the tube to make sure we know, or at least we think we know it actually has a tube in it ! It glows RED, it's gotta be good !
T

Yea, they send about 50 volts to the tube. A 12ax7 needs about 150v to function properly. Overdriving the input sends more heat to the tube, but it creates more of a tube distortion effect, rather than the clean round sound associated with the likes of Tube Tech or Manley stuff.

One of the Art designs, the MPA Gold, can send 150v to the tube. A switch marked "Normal/High" switched between SP and proper voltage. Probably should read, "Starved Plate/Normal."

Some guys have voiced glee with the GT12ax7c (I think c is for China). It's suppose to run better at lower voltage. I dunno. Also, I've heard of a 5851 tube, that is suppose to be a low-voltage version of a 12ax7, but I think it's a lotta bull.

[woodman]

the answer to the OP is a resounding YES! at least in my experience ...

had some free time over the weekend and dug out an old Mullard 12AX7 i had stashed and a 1985-vintage Groove Tubes 12AU7 (back when they relabeled older production tubes) and popped 'em into the Brick ... i expected maybe a slight improvement, but it was more like the preamp found a bigger voice. all the qualities of the tube experience were magnified — depth, warmth, and subtle but sweet compression.

i retracked a background vocal, and now it's got me wondering if ought to go back and retrack all the vocals ... reinventing the wheel! ... i probably won't, but i was surprised at the difference. of course YMMV!

[tonebro]

From your description, you'd want to put an NOS GE 5751 in there and you'll be fine.

[jimmynumber9]

Try different tubes to warm it up. Don't just listen to one person's input on one tube and an amp that could not be anything like yours. Your best bet is to experiment.