help! new preamp tubes!

_tom_ · December 15th, 2004, 11:48 AM

I rang up Watford Valves and Hot Rox UK and was told that these three are best for clean headroom.

JJ/Tesla ECC83
Groove Tubes 12AX7M (hot rox said these are the BEST)
Electro Harmonix Golds 12AX7EHG

i dont know which to go for. Watford valves say the JJ have best clean headroom but on Hot Rox UK's website it says "Great 12AX7 for blues/rock players
This tube clips slightly earlier than other 12ax7's giving you that edge." im a bit confused! the EHX are cheapest at £9.25. GT are £17.99 a tube which i think is a bit much. and i dont know how much the JJ are. which would you recommend for me to get, bearing in mind i want as much clean headroom as i can? oh and do i need to replace all 3?

thanks a lot

d. meyers · December 15th, 2004, 01:30 PM

I think you've discovered the secret: in my opinion, these guys are making claims about their tubes that are more or less hooey. I think you would really need to match individual tubes (of a specific type, i.e. all 12AX7's) to your specific amp to notice a difference in headroom- and even then I'm a little sceptical, although I'm no engeneer. Next time you talk to them, call their bluff and ask them to fax test data to you demonstrating their claims about the tubes. I'd bet their isn't any. Maybe one of the amp tech around here can give you a good reccomendation, but my guess is that youd have better luck (if you're going for a dramatic change) switching to a lower gain preamp tube if you want to clean your amp up. Also- 18 pounds for a 12AX7 sounds pretty insane to me- NOS RCA's should'nt be that much money, let alone a modern tube.

_tom_ · December 15th, 2004, 04:14 PM

right so what brand would you recommend i get not just out of them but every brand? i heard a 12AU7 is best for the preamp if you want more headroom? i could get anything off www.hotroxuk.com or http://www.tube-shop.com/home.asp .

d. meyers · December 15th, 2004, 05:45 PM

I had a look at both links, and frankly I have no idea. I've used a wide variety of cheap Chinese tubes over the years, and they are mostly(but not uniformly) lousy. I've had good luck with NOS US brands (I'm sure the UK brands are as good) as well as the recent JJ tubes, from the Slovak Republic, I think. For all I know many of the other brands on both sites are great- It's really trial and error with tubes, in my experience. As far as choosing a type, see:

http://thetubestore.com/gainfactor.html

I'd just buy the JJ's and be done with it. Fooling with tubes really isn't going to dramatically change the amp's headroom anyway, incremental changes are all you'll get, at best. Good luck...

Daniel

geddyleedog · December 15th, 2004, 05:55 PM

Quote:

Originally Posted by d. meyers

I'd just buy the JJ's and be done with it. Fooling with tubes really isn't going to dramatically change the amp's headroom anyway, incremental changes are all you'll get, at best. Good luck...

Daniel

I whole heartedly agree. I think you will find little to no difference in headroom between the 12AX7s. I buy JJs as well, and I get them from Eurotubes. Why? Bob is a great guy and he gives great service at good prices.

Tremo · December 16th, 2004, 02:47 AM

If you want clean headroom, just make sure the preamp tubes are healthy. The biggest factor in getting clean headroom is in the output tubes. Use the biggest and baddest outputs you can get, and bias them slightly cold.

Scotland · December 16th, 2004, 03:43 AM

Email him with your amp details and what you want, he will surprise you by giving you exactly the info you require and can supply you with the proper phase invertor valve / tube for your amp.

http://www.eurotubes.com/index.htm

_tom_ · December 16th, 2004, 09:43 AM

ok well i emailed tube shop and got the following response
"If you change your valves regularly then just change the first stage valve for an NOS 5751. You can order this at #17.50 by fax or phone on +44(0)870 9220404.
If you havent changed the tubes recently at all then order the Golden Dragon 12AX7 at #7.95each for stages 2 and 3. This should help clean up your sound and better than using a 12AT7"

i will email Euro tubes but im a bit wary about them being shipped over from the US, damage etc.

December 15th, 2004, 11:48 AM	#1 (permalink)
_tom_ Tele-Meister Join Date: Nov 2004 Posts: 138	help! new preamp tubes! I rang up Watford Valves and Hot Rox UK and was told that these three are best for clean headroom. JJ/Tesla ECC83 Groove Tubes 12AX7M (hot rox said these are the BEST) Electro Harmonix Golds 12AX7EHG i dont know which to go for. Watford valves say the JJ have best clean headroom but on Hot Rox UK's website it says "Great 12AX7 for blues/rock players This tube clips slightly earlier than other 12ax7's giving you that edge." im a bit confused! the EHX are cheapest at £9.25. GT are £17.99 a tube which i think is a bit much. and i dont know how much the JJ are. which would you recommend for me to get, bearing in mind i want as much clean headroom as i can? oh and do i need to replace all 3? thanks a lot

December 16th, 2004, 03:43 AM	#7 (permalink)
Scotland Poster Extraordinaire Join Date: Mar 2003 Location: Aberdeen, Scotland, Yewrup Age: 54 Posts: 6,612 3 Photos	Contact Bob Email him with your amp details and what you want, he will surprise you by giving you exactly the info you require and can supply you with the proper phase invertor valve / tube for your amp. http://www.eurotubes.com/index.htm __________________ All those who believe in psycho-kinesis, raise my hand !

December 15th, 2004, 01:30 PM	#2 (permalink)
d. meyers Tele-Meister Join Date: Feb 2004 Location: PDX OR Posts: 463 8 Photos	I think you've discovered the secret: in my opinion, these guys are making claims about their tubes that are more or less hooey. I think you would really need to match individual tubes (of a specific type, i.e. all 12AX7's) to your specific amp to notice a difference in headroom- and even then I'm a little sceptical, although I'm no engeneer. Next time you talk to them, call their bluff and ask them to fax test data to you demonstrating their claims about the tubes. I'd bet their isn't any. Maybe one of the amp tech around here can give you a good reccomendation, but my guess is that youd have better luck (if you're going for a dramatic change) switching to a lower gain preamp tube if you want to clean your amp up. Also- 18 pounds for a 12AX7 sounds pretty insane to me- NOS RCA's should'nt be that much money, let alone a modern tube.

December 15th, 2004, 04:14 PM	#3 (permalink)
_tom_ Tele-Meister Join Date: Nov 2004 Posts: 138	right so what brand would you recommend i get not just out of them but every brand? i heard a 12AU7 is best for the preamp if you want more headroom? i could get anything off www.hotroxuk.com or http://www.tube-shop.com/home.asp .

December 15th, 2004, 05:45 PM	#4 (permalink)
d. meyers Tele-Meister Join Date: Feb 2004 Location: PDX OR Posts: 463 8 Photos	I had a look at both links, and frankly I have no idea. I've used a wide variety of cheap Chinese tubes over the years, and they are mostly(but not uniformly) lousy. I've had good luck with NOS US brands (I'm sure the UK brands are as good) as well as the recent JJ tubes, from the Slovak Republic, I think. For all I know many of the other brands on both sites are great- It's really trial and error with tubes, in my experience. As far as choosing a type, see: http://thetubestore.com/gainfactor.html I'd just buy the JJ's and be done with it. Fooling with tubes really isn't going to dramatically change the amp's headroom anyway, incremental changes are all you'll get, at best. Good luck... Daniel

December 16th, 2004, 02:47 AM	#6 (permalink)
Tremo Banned Friend of Leo's Join Date: Mar 2003 Location: Silicon Valley, CA, USA Posts: 3,803	If you want clean headroom, just make sure the preamp tubes are healthy. The biggest factor in getting clean headroom is in the output tubes. Use the biggest and baddest outputs you can get, and bias them slightly cold.

December 16th, 2004, 09:43 AM	#8 (permalink)
_tom_ Tele-Meister Join Date: Nov 2004 Posts: 138	ok well i emailed tube shop and got the following response "If you change your valves regularly then just change the first stage valve for an NOS 5751. You can order this at #17.50 by fax or phone on +44(0)870 9220404. If you havent changed the tubes recently at all then order the Golden Dragon 12AX7 at #7.95each for stages 2 and 3. This should help clean up your sound and better than using a 12AT7" i will email Euro tubes but im a bit wary about them being shipped over from the US, damage etc.