Help me find a valve for my Alembic F-1X

[Ghost_Bass]

Not sure this is the right place to post this (if not i ask a moderator to please move it to the right place).

I recently bought a F-1X and it's valve (still the original one, after 18 years) isn't at it's best, it has lost too much output when i compare it with a EHX 12AX7 i have at home.

I'v been doing some research and found this very interesting topic:
[url="http://basschat.co.uk/topic/122331-the-humble-12ax7-vs-the-lesser-used-5751/page__hl__alembic%20f1x%20valve"]http://basschat.co.uk/topic/122331-the-humble-12ax7-vs-the-lesser-used-5751/page__hl__alembic%20f1x%20valve[/url]

It convinced myself (after reading obbm's post) to get a NOS 5751 valve but my question is: Wich one? I'm not fully aware of the valve market and on top of that the F-1X has a metal sleeve for the valve that doesn't alow room for just any valve to fit in, they can't be too "fat".

I'm looking for some advise from BC'ers as to places to buy good valves and good brands. Also F-1X owners who had replaced their valves and wich they ended up using.

If any BC member has some spare valves and is willing to ship i'll be more than happy to buy one.

One other thing, at this time let's say that price isn't an object for a very good NOS 5751 valve, of course i'm not going to spend £100 on one but i don't mind paying a premium for a very nice thing.


All help will be most welcome, cheers

Marco

[paul_5]

In the UK I'd give Watford Valves a call. I've had nothing but great advice and customer service from them, particularly Derek, who knows practically everything about valve amps - it's a long conversation but fascinating.

[url="http://www.watfordvalves.com/index.asp"]http://www.watfordvalves.com/index.asp[/url]

Most preamp valves of this type (12AX7, 5751, ECC83 etc…) tend to be a uniform size and have a standard 9 pin array at the bottom, and are all skinny valves .

Edited December 18, 2013 by paul_5

[Ghost_Bass]

I'm in Portugal, a phone call to UK isn't very cheap and if you say it will be a long conversation then even worse!

The EHX i had at home is a bit too fat for my f1x. The only way i could manage to fit it was to take out the moving bit from the metal sleeve. Its the interior (upper) one shown in this pic i stole from the web:


The tip of my valve is now showing, it's the glass part that's painted silver.

[chris_b]

[quote name='Ghost_Bass' timestamp='1387387117' post='2311426']
....I'm in Portugal, a phone call to UK isn't very cheap....
[/quote]

Can you email them?

I'd also email Alembic and ask them.

[Ghost_Bass]

[quote name='chris_b' timestamp='1387390331' post='2311473']
Can you email them?

I'd also email Alembic and ask them.
[/quote]

Sure i can but Alembic doesen't support any specific valves for their f1x, they stick whatever they can source that meets their criteria. As to watford valves i'm sure they know a lot about valves but is the guy who's going to answer me a bass player? And does he have a f1x?

I'm looking for opinins from, BCers who in fact own or owned one of these and tried diferent valves on them, I think this firs person experience it will be more helpfull than an e-mail full of (very usefull) tech talk.

Cheers

[Acebassmusic]

Hi,

I've got an Alembic F1X and swapped out the standard tube for a RCA 5751 and have used a GE 5751 as well. Both tubes run at approx 70% gain of the typical 12AX7 so you wont get the same volume or ability to add "distortion" out of them. I wasn't looking for volume or distortion when I chose the 5751's but a smoother sound with lots of clarity. I did a bit of research (geekery!) and found quite a bit of info both on here and Talkbass etc. When I get home I will try and remember to edit my post with some of the links if I can find them.

Regarding fitting - I have had no problems fitting any replacement tubes into the carrier / sleeve.

[obbm]

I used an NOS Philips 5751 in both my F1X and a BMAX-T. I got it from Colomor Valves in Billinghurst in Sussex, UK.

They sell directly but also on Ebay.

[url="http://www.ebay.co.uk/itm/5751-JAN-PHILIPS-ECG-ECC83-12AX7-NEW-TUBE-VALVE-1-PC-/390151251894?pt=UK_Sound_Vision_Valves_Vacuum_Tubes&hash=item5ad6d3a7b6"]http://www.ebay.co.uk/itm/5751-JAN-PHILIPS-ECG-ECC83-12AX7-NEW-TUBE-VALVE-1-PC-/390151251894?pt=UK_Sound_Vision_Valves_Vacuum_Tubes&hash=item5ad6d3a7b6[/url]

[6v6]

[quote name='Ghost_Bass' timestamp='1387418190' post='2311835']
Sure i can but Alembic doesen't support any specific valves for their f1x, they stick whatever they can source that meets their criteria. As to watford valves i'm sure they know a lot about valves but is the guy who's going to answer me a bass player? And does he have a f1x?

I'm looking for opinins from, BCers who in fact own or owned one of these and tried diferent valves on them, I think this firs person experience it will be more helpfull than an e-mail full of (very usefull) tech talk.

Cheers
[/quote]

IMHO you are over thinking this. You need one replacement 12AX7 tube, there are thousands out there new and NOS, any of which will work OK in your preamp, buy a few and see which ones you like.

Also FWIW, I've got good real-world advice from Watford Valves in the past, not just "tech talk", and the F1-X contains probably the absolute most commonly used preamp circuit of all time (it's a completely standard Fender preamp stage), so I'd be amazed if they don't have experience of testing with it.

[Ghost_Bass]

[quote name='Acebassmusic' timestamp='1387443867' post='2311918']
Hi,

I've got an Alembic F1X and swapped out the standard tube for a RCA 5751 and have used a GE 5751 as well. Both tubes run at approx 70% gain of the typical 12AX7 so you wont get the same volume or ability to add "distortion" out of them. I wasn't looking for volume or distortion when I chose the 5751's but a smoother sound with lots of clarity. I did a bit of research (geekery!) and found quite a bit of info both on here and Talkbass etc. When I get home I will try and remember to edit my post with some of the links if I can find them.

Regarding fitting - I have had no problems fitting any replacement tubes into the carrier / sleeve.
[/quote]

This is exactly the kind of reply i'm looking for. This is the result i'm looking for, i'm running the f1x through a 1kW (bridged at 4ohms) poweramp and sending it to the S12T, i'm not worried about the volume drop of the 5751, in fact i think it will help me get the volume pot past 1 or 2/10 and gain a bit more room for manoeuvre.

I forgot to take a pic after fitting the EHX 12AX7 but that one is really too fat for the sleeve. I've read posts on the Alembic forum, by Mica, saying that there are many valves that doesn't fit the sleeve and they (Alembic) have a lot of tubes on storage that are too big for their preamps. This is the reason why i'm concerned about size. Your post is a bit more reassuring though

[quote name='obbm' timestamp='1387448676' post='2311984']
I used an NOS Philips 5751 in both my F1X and a BMAX-T. I got it from Colomor Valves in Billinghurst in Sussex, UK.

They sell directly but also on Ebay.

[url="http://www.ebay.co.uk/itm/5751-JAN-PHILIPS-ECG-ECC83-12AX7-NEW-TUBE-VALVE-1-PC-/390151251894?pt=UK_Sound_Vision_Valves_Vacuum_Tubes&hash=item5ad6d3a7b6"]http://www.ebay.co.u...=item5ad6d3a7b6[/url]
[/quote]

Thanks for the link, i'll check it out.

[quote name='6v6' timestamp='1387448721' post='2311986']
IMHO you are over thinking this. You need one replacement 12AX7 tube, there are thousands out there new and NOS, any of which will work OK in your preamp, buy a few and see which ones you like.

Also FWIW, I've got good real-world advice from Watford Valves in the past, not just "tech talk", and the F1-X contains probably the absolute most commonly used preamp circuit of all time (it's a completely standard Fender preamp stage), so I'd be amazed if they don't have experience of testing with it.
[/quote]

You're right and i understand that. I may be overthinking surely but in my idea it would be easier for me to try a couple of valves that have been road tested by BC members and have a good opinion of them instead of just keep buying and trying a whole bunch of them. I'm more inclined for the 5751 because i'm not looking for saturation, only big clean headroom


BTW, here's a pic of the valve that came with the preamp:



Any idea of what this could be? No markings on it. Is there any way to even identify the type of valve (12AX7 ou other)?

Cheers

[jazzyvee]

I'll be interested in the solution as I too have an F1-x and it would be good to have one or two spare clean sounding valves knocking around.
Jazzvee

Edited December 19, 2013 by jazzyvee

[brensabre79]

It's very likely the original tube is no longer made. It may have come from the US.

The width on these valve types will vary slightly from manufacturer to manufacturer, but you should probably look for a NOS Philips, RCA or Sylvania (make sure it's made in USA) as they will be more likely to be a direct replacement for what you have.

however, the sleeve is probably not essential to the opewration of your pre-amp. Most people don't bother with them unless the valve is exposed.

You will always get better advice from speaking to an expert.

If it were me, I wouldn't pay NOS money - there's always a chance they are rubbish (especially off eBay). I would go to [b]Watford valves[/b], ask for some advice (by email if you prefer) and take delivery of a suitable valve safe in the knowledge that it's probably the right one for the job, it will also be tested. And even if it's not right you can send it back for a replacement.

[Ghost_Bass]

Thanks for the info Bren, yep from what i've been reading those brands are on the top 5 (Telefunken and Mullard complete the list).

[dan670844]

[quote name='Ghost_Bass' timestamp='1387377323' post='2311264']
Not sure this is the right place to post this (if not i ask a moderator to please move it to the right place).

I recently bought a F-1X and it's valve (still the original one, after 18 years) isn't at it's best, it has lost too much output when i compare it with a EHX 12AX7 i have at home.

I'v been doing some research and found this very interesting topic:
[url="http://basschat.co.uk/topic/122331-the-humble-12ax7-vs-the-lesser-used-5751/page__hl__alembic%20f1x%20valve"]http://basschat.co.u...c%20f1x%20valve[/url]

It convinced myself (after reading obbm's post) to get a NOS 5751 valve but my question is: Wich one? I'm not fully aware of the valve market and on top of that the F-1X has a metal sleeve for the valve that doesn't alow room for just any valve to fit in, they can't be too "fat".

I'm looking for some advise from BC'ers as to places to buy good valves and good brands. Also F-1X owners who had replaced their valves and wich they ended up using.

If any BC member has some spare valves and is willing to ship i'll be more than happy to buy one.

One other thing, at this time let's say that price isn't an object for a very good NOS 5751 valve, of course i'm not going to spend £100 on one but i don't mind paying a premium for a very nice thing.


All help will be most welcome, cheers

Marco
[/quote]

Hey Marco,

I would stick to a 12AX7, you need a certain amount of gain to get a FMV tonestack cooking. This tone stack is lifted straight out of a Fender showman. In my experience if you use a lower gain tube in this type, the bandwidth starts to narrow and you loose the high and lows and the sensitivity of controls. If you are looking for a cleaner sound, I would work on the level of the signal you are putting in. A slight bit of harmonic distortion and compression is what its all about. I would have a look at the Gold Lion reissue 12AX7 its a great valve in this application as its very warm and musical the bass definition is superb and its dead quiet. Karltone is the best place to get these from. A new valve takes a while possibly up to 10 hrs to sound its best. I usually run some music through my amps for a while to burn the tubes in. If yo get any trouble getting hold of one I transit back from Porto to London quite a bit!! I live in Foz!!

[Ghost_Bass]

[quote name='dan670844' timestamp='1387458838' post='2312172']
Hey Marco,

I would stick to a 12AX7, you need a certain amount of gain to get a FMV tonestack cooking. This tone stack is lifted straight out of a Fender showman. In my experience if you use a lower gain tube in this type, the bandwidth starts to narrow and you loose the high and lows and the sensitivity of controls. If you are looking for a cleaner sound, I would work on the level of the signal you are putting in. A slight bit of harmonic distortion and compression is what its all about. I would have a look at the Gold Lion reissue 12AX7 its a great valve in this application as its very warm and musical the bass definition is superb and its dead quiet. Karltone is the best place to get these from. A new valve takes a while possibly up to 10 hrs to sound its best. I usually run some music through my amps for a while to burn the tubes in. If yo get any trouble getting hold of one I transit back from Porto to London quite a bit!! I live in Foz!!
[/quote]

Hi Dan, thanks for the tips and the kind offer (my drummer lives in Porto so we never know if i wont take up on your offer sometime).
My basses have a hot output, the Ken Smith is the hottest, i think that i may not loose much with the 5751 but i've been thinking and i'm now inclined to go a diferent route on this.

I've been offered a JJ Tesla 5751 by Gareth over here on BC, it's a modern, common and cheap valve so i think i'll take that one and do a bit of AB comparisson at home with the 12ax7 EHX. Then i'll get a proper man's NOS valve of the kind i found working best for my sound.

Cheers

[BassBod]

I've had several in my F2B over the years. GE 5751's sound very good, but you do notice a slight gain reduction. EH and Sovtek LPS 12AX7 also sound great, but are more aggressive and middy. I've had GE 12AX7's in for a few years and they are fine. The only valves I dislike are Groove Tubes removed from various 90's SWR amps - they always sound harsh and edgy to me.

To be honest, I can only hear differences in isolation - you aren't going to hear anything that's very significant in a gig context. As long as its working to spec it will sound good.

My F2B has never had metal tube shields fitted, so I wouldn't be too bothered unless you can hear an increase in background hum/noise without it. It also had (original?) Amperex valves (1978 or older?) fitted, which I've had in my SWR amps for years…still working fine.