Author Topic: Do you have a f avorite Tube for you F1-X? (Read 719 times)

mrfunkwool · « **on:** October 01, 2005, 05:55:07 AM »

I think my tube is starting to go on my F1-X.

I'm using the crossover and the high pass channel has become very weak as of late. So I'm hoping its just the tube. My fingers are crossed.

Anyways, Does anyone have a favorite tube manufacturer for the 12AX7-WB?

Or maybe you know of a different 12AX7 model that will fit. I bought the Fender 12AX7-WC which is slightly too big to fit in the sleeve.

Thanks Jeff

emjay · « **Reply #1 on:** October 19, 2005, 03:38:23 PM »

I've been buying vintage high-testing tubes on Ebay for a little while now. I wanted a rounder, richer tone from the SWR amps I have. Each amp will have it's own effect on the tube's microphonics, so I can't tell you about the FX-1; but the British Mullard NOS (New Old Stock) tubes from the 60's I bought sound so much different than the Groove Tubes, it's like night and day. So much more tonal responsiveness, louder, sweeter and rounder overdrive, great growl, and less hiss at loud volumes. Worth every penny of the $85 I paid for them. It's almost like getting differnt amps! I'll try the Bugle Boy and Telefunken tubes next, just to see if there's the brand difference I've been reading about.

Can't tell you about the sleeve fit, as older 12AX7 tubes vary a bit in shape. Maybe Mica or someone else in the house can???

Happy hunting! Another Jeff

mica · « **Reply #2 on:** October 19, 2005, 04:27:40 PM »

At various times we've had to reject up to half the tubes we buy for being oversized. Other times, there are no rejects. Quality control for this dimension is apparently spotty.

When you say the high pass channel is weak do you mean it has reduced output? If so, it's may not be your tube at all, it might just need a cleaning.

gare · « **Reply #3 on:** October 20, 2005, 05:29:16 AM »

Jeff,
If you haven't already checkout www.eurotubes.com/.
I've used them several times, knowledgable, reasonable prices, and quick service.

kmh364 · « **Reply #4 on:** October 21, 2005, 05:15:46 AM »

Jeff:

This is what my amp guru said about tubes...this is specifically in referrence to my custom, hand-made, hard wired hot-rodded Marshall Plexi-style amp, but are appropos to anything using 12AX7's (there's some Power Tube advice in there as well):

In my opinion preamp tubes will make a larger impact on the tone than power tubes in this amp. My preference is to use mullard, brimar or amperex 12ax7's in the preamp section........I have had excellent luck with them but they are pricey. Older GE preamp tubes are also an upgrade over the newer tubes and more reasonable on price.
For power tubes, Mullards are just too damn expensive. I have a set that I use for testing amps and for my own use, but when they die I won't buy another set unless I get them for a song. For my daughters amp I used GE 6CA7 fat bottle tubes. These are what EVH supposedly used back 70's and I personally like them better than Mullards. I think the last set I bought I paid about $80 for the pair off Ebay which is pretty reasonable. You can find them under GE, Sylvania or National brand, but they are distinctive because of their wide/fat bottle shape, more like a 6L6 shape. Another great option is Seimens EL34's......these are still fairly common and sound great. I currently have a real plexi in for repair that is using them. They don't recommend them for Plexi's because they can only take a plate voltage of 450v(and many Plexi's are above that), but your amp is right around 445, so you are right on the edge. Folks really like them and they are really reasonable.....check out www.angela.com for these. Last time I checked Steve had matched pairs for about $60!(a really great price).
If you really want Mullards, I prefer the xf-2's (60's tubes), but the xf-4's are good too. xf-2's will run about $250-350 a pair which is just nuts, xf-4's should be cheaper. I wouldn't pay more than $100 for power tubes, but that is just my opinion.
I ended up using JJ tubes in yours, they are really good and stable tubes. The preamp tubes are pretty quiet and the power tubes are really rugged. I hated the Svetlana tubes I had purchased for them, so I am using them for firing up new amps and ones that I am repairing.
Don't forget if you do change the tubes, get matched pairs(matched for current) and you will need to have the amp rebiased, especially with old stock tubes.

Here's where he buys his tubes:

http://www.cedist.com/

http://www.angela.com/

http://tubeworld.com/index_high.htm

If you find a cheap place to get the NOS Mullards, lemme know cause I'd really like a trio for my amp, as well as, a pre-amp tube for my Eden WT-550 bass head.

Cheers,

Kevin

kmh364 · « **Reply #5 on:** October 21, 2005, 05:20:19 AM »

Mica:

Do the FX-series preamps utilize standard tube RF shields, or is it a special sleeve that Alembic uses?

If it's the former, then finding a std. tube shield shouldn't be a probelem. If it's the latter, then you'll just have to find tubes that fit..trial and error, as it were.

If you find any NOS Mullard 12AX7's that don't fit, send 'em my way...I will take 'em off your hands! I also have a (silverface) Fender Twin that could use a set as well!

edwin · « **Reply #6 on:** October 21, 2005, 07:12:15 PM »

Tubes vary a lot, even in the same brand. Often, these days, a brand doesn't even tell you that much about who made the tube in the first place. I have been getting my tubes from Fat Willie in Denver, at NBS Electronics. He's very reliable and the prices are right. He's also known on the net as Lord Valve, and has developed quite a reputation for his political views. Even though I don't agree with them, he does get my thumbs up for his business practices.

Anyway, I have discovered that the effect of spending a lot of money on tubes can be highly variable depending on what amp or preamp they are going in. My F1X seems to be a lot less affected tonally than my F2B or Fender amps when it comes to different varieties of 12AX7s (or variants thereof. I really like the 5751s in my Showman). For something like an F1X, I wouldn't spend a huge amount on spendy tubes, whereas for an old Fender, Marshall, Vox, or F2B, I might be more tempted.

Just my 02c.
Edwin

kmh364 · « **Reply #7 on:** October 24, 2005, 05:18:08 AM »

Well, since you only need a single tube for an F-1X, the additional cost of an NOS 12AX7 tube wouldn't dent the wallet too bad.

What's the difference in the circuit architecture between the F-1X and F-2B, other than the dual mono layout of the F2-B? Specifically, I'm interested in why there's an apparent difference in the contribution of sound atributed to pre-amp tubes(s) between the two, as reported by Edwin.

Inquiring minds wanna know! LOL!

Cheers,

Kevin.

edwin · « **Reply #8 on:** October 25, 2005, 02:14:07 AM »

In the F1X, the tube is used as an input buffer and in the FX loop return (I think that's where the other half is used). If I recall correctly, the tube is used in a unity gain setting. The gain comes from solid state op amps. The F2B is all tube, there is no silicon at all in the box.

I wouldn't say that one approach is better than the other (although for my taste, I like the F1X better), just different. It would be kinda cool if the F2B were an actual dual version of the F1X, but I guess to get that kind of functionality, I would have to buy two F1Xs.

Anyway, do like me and get one of each and whole buncha tubes and try them all out!

Edwin
PS don't forget to get the SF2 while you are at it!

kmh364 · « **Reply #9 on:** October 25, 2005, 06:17:49 AM »

AH! I figured there must be some S.S. stuff in there mucking about with the sound, LOL! You can't beat the euphonic coloration of tubes...the rose-colored glasses of the audio world, LOL! If you can't already tell, I love valves!

SF-2? MORE knobs to tweek? If nothing else, Alembicians are knob-twiddlers, LOL! I'm still having trouble coming to grips with all those knobs on my EMW-equipped Alembic and my Eden head! Adding more would only serve to cause my overloaded cranium to explode, LOL! There is something to be said about plug-n-play, although if there wasn't a need for versatility, the Alembic probably wouldn't exist.

Cheers,

Kevin

mrfunkwool · « **Reply #10 on:** October 25, 2005, 10:10:42 AM »

Thanks for all the responses!

Shortly after my posting, a guy appeared on Craig's list in Boston. selling new NOS NIB Mullard CV4024/Mil 12AT7 sub 12AX7 made in 1983.
$17 for one.

This tube has worked out great for me.

I also tried a newer Groove tube also $17, which I think is supposed to be modeled after the mullard. Although I prefer the sound from the mullard from 1983.

Of course both of these sound great, cuz my high pass is back, which was my original concern.

kmh364 · « **Reply #11 on:** October 25, 2005, 12:09:52 PM »

Jeff:

No prob. Good on ya! I don't think you can go wrong with the Mullard, and your problem is history. Stock up on known good versions so you have 'em when you need 'em.

Cheers,

Kevin

edwin · « **Reply #12 on:** October 25, 2005, 04:28:03 PM »

I was afraid that if I brought up the different uses for the tube in the two circuits, there might be some negative implications suggested about the use of solid state components. I don't think you were knocking the F1X, but in my experience, the solid state parts don't muck up the sound at all. All these things depend on the context of the circuit. In fact, the tube stuff I love tends be very untubelike. Tubes can be very clear and clean sounding,very uncolored, while some solid state devices can be be warm and vintage in sound (no tubes in a Neve preamp) with lots of character. As usual, let your ears be the judge and don't listen to hype.

Edwin

kmh364 · « **Reply #13 on:** October 25, 2005, 05:32:46 PM »

As in everything else in life, execution is everything. I was joking about the S.S. stuff. I 've been a HiFi nut for nearly 30yrs, so I understand that specs. mean nothing...sound is everything. I do tend to gravitate towards tubes for my guitar/bass stuff and S.S. for my HiFi stuff. Having said that, I find a combo of both can be quite satisfying as well: My Eden WT-550 bass head is one, the ARC LS-2B hybrid (hi-fi) pre-amp is another, for example.

While I'll certainly listen to what others have to say, just remember the ole chestnut opinions are like *-h*les, everyone's got one and they all stink, LOL! Seriously, hype has little meaning to me if the sound doesn't equal or exceed the hype. I'm not out to impress anyone but myself...I'm just always interested in trying to find what I feel is the finest available of everything, budget not withstanding, LOL!

Cheers,

Kevin

bassdr · « **Reply #14 on:** November 15, 2005, 07:58:06 AM »

I bought an NOS GE 12AX7 made in 1968 recently to replace the Groove tube that came in my F-1X when I bought it used. Much better sounding and quiet. Michael (Flame Koa Essence)