Alembic F1X users. Ever change your tube......

[Chunk-O-Funk]

and break it?


While I was google'n on how to take the tube out of that stupid little sleeve they use to keep it from vibrating, I, of course came across the Alembic web site (which was no help) and found users stating there is little to no sound difference when upgrading the tube in this preamp do to some SS electrons in the tube circuit.

Just wondering if anyone has experimented with different tubes in their F1X and what kind of results there might have been.

Even though it maters less now that I actually need a new tube I would still like to hear opinion.

 

[Ostinato]

I've changed the originals with a pair of nice NOS Tungsrams...and like many others, I've noticed little difference in tone.

One thing I do notice though...the difference a dirty jack can make on tone, a dirty jack will make an Alembic sound like garbage so I advise everybody to get out the alcohol and Q-TIPS and give 'em a good scrubbing.

 

[Trevorus]

I think changing the tube type rather than tube brand would make more of a difference. Like subbing in a 12at7 instead may give it a different character.

 

[Chunk-O-Funk]

I think changing the tube type rather than tube brand would make more of a difference. Like subbing in a 12at7 instead may give it a different character.

That's a good idea.

The only thing is on the F1X, there is a metal sleeve that is very tight around the tube, so if the 12at7 is any bigger in diameter it wont fit. The sleeve is also why I broke my tube. Absolutely no room to rock it back and forth or to get a hold of it enough to pull it out. The tube is actually recessed into this sleeve.

 

[Trevorus]

That's a good idea.

The only thing is on the F1X, there is a metal sleeve that is very tight around the tube, so if the 12at7 is any bigger in diameter it wont fit. The sleeve is also why I broke my tube. Absolutely no room to rock it back and forth or to get a hold of it enough to pull it out. The tube is actually recessed into this sleeve.

Got any pics? The 12a__7 tubes should all be the same dimensions, so you shouldn't have any problems with that, other than what you are already experiencing.

 

[Chunk-O-Funk]

Got any pics? The 12a__7 tubes should all be the same dimensions, so you shouldn't have any problems with that, other than what you are already experiencing.

No, no pics.

I'm going to send an email to Bob at euro tubes. I'm going to be re-tubing my Mesa Boogie, so I figured I would get one more preamp tube for the F1X and see if is was any better.

I'll see what he recommends. Maybe I'll get one 12AX7 and one 12AT7.

Thanks.

 

[Ostinato]

That's a good idea.

The only thing is on the F1X, there is a metal sleeve that is very tight around the tube, so if the 12at7 is any bigger in diameter it wont fit. The sleeve is also why I broke my tube. Absolutely no room to rock it back and forth or to get a hold of it enough to pull it out. The tube is actually recessed into this sleeve.

Take some masking tape and wrap it round the top of the tube and pinch it off. Then grab the tape and wiggle it out.

 

[Chunk-O-Funk]

Take some masking tape and wrap it round the top of the tube and pinch it off. Then grab the tape and wiggle it out.

Too late! Me make glassy thing go crack.

Thanks though, I'll try that if there is a next time.

 

[pdbass]

I remember changing the tube in my F1-X a couple of years back. I really barely noticed, but the soundman went NUTS. He was freaking. He said that the bass sounded so much better. So much fuller. So, either my ears aren't as developed or the new tube really made a difference in my DI signal. $0.02

 

[Ostinato]

Too late! Me make glassy thing go crack.

Thanks though, I'll try that if there is a next time.

ok then needlenose pliers and a pot of coffee.

 

[zombywoof5050]

I certainly noticed an appreciable difference in tone when I tried out various tubes in my F-2B. Maybe it's different with the F-2B, which has no SS components. For instance, the Telefunkens sounded much better than the Groove Tubes.

 

[A9X]

Take some masking tape and wrap it round the top of the tube and pinch it off. Then grab the tape and wiggle it out.

Always remove a tube by handling it near the base of the glass envelope.

 

[Michael Vee]

Chunk-o, search for the F1-X Megathread. There's more info in there about tube changes.

 

[Chunk-O-Funk]

I remember changing the tube in my F1-X a couple of years back. I really barely noticed, but the soundman went NUTS. He was freaking. He said that the bass sounded so much better. So much fuller. So, either my ears aren't as developed or the new tube really made a difference in my DI signal. $0.02

That's good news. FOH sound is just as important as whats coming out of the amp.

I only briefly read some through some of the threads over at Alembic. It might have something to do with where the tube is in the signal path. Pre and post gain, EQ, or something. I could be wrong though.

ok then needlenose pliers and a pot of coffee.

HA HA! That's what got me here. Pliers with some electrical tape around the tip with the sticky side out. The tiny little tip of glass broke off and of course make a hole on the top of the tube.

Always remove a tube by handling it near the base of the glass envelope.

Impossible with this preamp. There is a sleeve that keeps the horizontally mounted tube from vibrating out of it's socket. The sleeve is not removable.

Chunk-o, search for the F1-X Megathread. There's more info in there about tube changes.

Thanks, I'll check it out. Thanks!

 

[Chunk-O-Funk]

Chunk-o, search for the F1-X Megathread. There's more info in there about tube changes.

I'm almost crying.

I actually looked at this thread before I had tried to take the tube out, but I never continued to the last page. Wish I had now.

I finally broke down and bought some new speaker cables from our pal Butch Ammons. I've been needing new ones for a couple of years.

Butch started selling tubes recently, so I said, what the heck, let's swap out the tube in the F-1X. So, the order arrived yesterday with a JJ/Tesla ECC83s / 12AX7 - dual triode, spiral filament tube.

The top of an F-1X is held on with eight small Allen head (hex) screws, four on each side. After getting these off, I checked the Alembic website for instructions. You have to wiggle the top half of the tube shield down until it nests into the bottom half, then work the tube loose. It's a very good idea to work the tube loose with one hand, while supporting the circuit board with the other!

Got the stock tube out, and the JJ/Tesla went right in. It fit the tube shield better than the stock tube! The cover went back on okay, except two screws just did not want to go back into place due the case being ever so slightly bent from rackmounting.

So- how does the JJ/Tesla sound? It's not a dramatic difference from the original tube, but it's a bit cleaner and more dynamic. Notes flow together in a passage just a bit better. There is much less crackling and extraneous noise.. the preamp is silent. It was well worth the $9.

The original tube was 13 years old. It didn't have a great deal of actual time on, but perhaps it was aging a bit. I'm not sure, but I do know the F-1X has its personality back in full.

So, the tube sleeve is in two pieces. The top half slides down into the bottom half. I just did it,....and whadaya know! pfft, it worked.

Well,..at least it wasn't an expensive lesson, and I was going to change the tube anyway.

It's also good to hear the JJ tube is slightly better and will fit into the sleeve. That's the tube I'm ordering.

Thanks!

 

[Chunk-O-Funk]

Also,

I've read your post and Alembics about exercising the jacks. I've had the same problem when I first took it out of storage. Good advise.

I also read the same thing about the tube socket. If that gets corroded or dirty it can make your preamp scratchy sounding.

Great thread Mike.
Wealth of information.

 

[A9X]

Impossible with this preamp. There is a sleeve that keeps the horizontally mounted tube from vibrating out of it's socket. The sleeve is not removable.

It looks like a shielding tube. They're common in RF eg radio recievers and in some audio applications with small signals and high gain, eg MI preamps and phono RIAA amplifier stages. They're usually a bayonet type connection with the tube socket.
Invalid Link Removed

 

[DanGR]

I've owned the Alembic F-1X for almost 20 years. I'm glad you found the info on the sleeve sliding down. I can tell you from many years of changing tubes in mine 2 things. First is that not all 12AX7 tubes will fit in the narrow sleeve. I've resorted to using skinny ECC83 tubes. Secong there may not be that much difference between tubes as far as tone goes, but changing tubes on a regular basis has shown me that a new tube increases warmth, punch, and decreases noise. When I've been using mine on a regular basis I've changed my tube about once a year. It doesn't cost that much and makes a world of difference in that great tone you get from the Alembic F-1X. No better preamp in the world IMO.

 

[Bassicmusik]

Guys, thank you for your helpful advices! When I openend my F1X I found a Sovtek Tube inside. Thanks to your advices, I changed it to a Mullard clone (Groove Tubes 12ax7m). It just took less than 10 minutes.
The sound is not spectacular different, but it’s smoother, has more punch and dynamic.
This is, what I expected. By the way, the Groove Tube 12ax7m fits perfect.

Best regards,
Chris

 

[Jim C]

I had an older Alembic that was used to warm up DI boxes in the studio.
We could hear virtually no difference between the Groove Tubes that were in it vs. Vintage Telefunkens and Mullards.
This was through a Neve console or for live use with a power amp. IMO, these pre's just need a decent quality tube that meets specs as I couldn't find any gold in tube rolling.

I never had any interest in changing the gain structure so always stayed with 12AX7's.