Valve advice for Croft Charisma

[mido]

Hello everyone,

I am about to purchase an upgraded Croft Charisma and am after a little advice with regards to the valves. This is my first foray into the world of valves so I am completely clueless.

The guy I am buying from says that the amp currently has some TAD valves in situ, but that he has a source of NOS Philips ecc82/83 valves which he says go well in the amp and he will install these for me should that be my wish.

What prompted me to buy this pre was a friend who brought his valve pre over and I had the realisation that not all valve equipment necessarily sounded warm and cuddly, but could sound clean, clear, crisp with tight bass and dynamics. This is what I like and I wouldn't want valves that sounded any other way. I don't want too warm or bloated etc.

With this in mind, would the Philips ones suit? Or would I be better off asking him to leave the current ones in situ? Or, would I be better off with something other than either of these two options?

All advice welcome. Thanks in advance.

[mido]

One other thing:

The seller has also offered me 3 options with regards to the potentiometer, Ko-on, Tkd or Audio Note. He recommends the KO-ON saying that "it fits the pre amp very well. Very extended and fluid."

Does anyone have any advice with regards to these options?

Thanks,

Frank

[Frankyc2003]

Hello everyone,

I am about to purchase an upgraded Croft Charisma and am after a little advice with regards to the valves. This is my first foray into the world of valves so I am completely clueless.

The guy I am buying from says that the amp currently has some TAD valves in situ, but that he has a source of NOS Philips ecc82/83 valves which he says go well in the amp and he will install these for me should that be my wish.

What prompted me to buy this pre was a friend who brought his valve pre over and I the realisation that not all valve equipment necessarily sounded warm and cuddly, but could sound clean, clear, crisp with tight bass and dynamics. This is what I like and I wouldn't want valves that sounded any other way. I don't want too warm or bloated etc.

With this in mind, would the Philips ones suit? Or would I be better off asking him to leave the current ones in situ? Or, would I be better off with something other than either of these two options?

All advice welcome. Thanks in advance.

That's really exciting Frank. I had a Charisma pre once. Croft stuff sounds great and never feels cuddly, soft or warm. It is a great preamp in my opinion.
As for the valves, ecc83 (12AX7 US denomination) and ecc82 (12AU7 US denomination) are some of the most common valves available. So your scope for 'tube rolling' is huge.
2 routes open in front of you though:

- you can go an source some NOS valves (new Old Stock). Basically valves that have never been used and ended up forgotten for years in a dusty warehouse for example.
- Brand new stuff from some from ex eastern block or chinese factories.

So, NOS wise, I would try to source some Mullard (UK manufactured til 80's roughly, some very sought after early vintages 60's). They tend to be quite pricey. But they do have a clarity quality to them that is undeniable. Cheaper and easier to source out, are some Military grade valves named CV4003 (ecc82) or CV 4004 (ecc83). Used in military applications they had to go through much more stringent tests than normal stuff, so reliability is very high on those valves. Sonically, again you are looking at very low micro phonics, hence good balanced sound. Finally you can try to source out some Telefunken, these have a legend`ry following online and can be very very pricey! One rule of thumb when buying NOS valves is to be able to trust the seller. Some duffer are always being flogged on eBay and could prove to be a very bad investment. A bad valve can really damage your equipment, so be vigilant.

On the brand new front, fortunately those reliability issues are most of the time not a problem. You could try some nice JJ Electronics valves, some Tung Sol, some chinese PSVANE, some Electro Harmonix, all have distinctive sounds, but to be honest the differences are subtle at first. So don't expect 'Night n Day' differences.

Overall, Ecc82 and Ecc83 are very affordable (mostly) valves and plenty of fun to play with. Just make sure you don't burn your fingers by swapping them while still hot!

Online places to get interesting valves would be in my books first LANGREX, then probably HOT ROX and WATFORD VALVES. All offer great service in my opinion. Then the dreaded eBay...

Enjoy this new valve world of fun!

[mido]

Thanks for all the advice Francois, it's good to hear that Croft might very well be the best choice for someone like me, with my tastes.

Also, very good to know where to and where not to buy these things, as well as what to look out for. So, thanks for that too.

And, I had wondered what all this 'military grade' stuff meant :lol:

[The Black Adder]

One other thing:

The seller has also offered me 3 options with regards to the potentiometer, Ko-on, Tkd or Audio Note. He recommends the KO-ON saying that "it fits the pre amp very well. Very extended and fluid."

Does anyone have any advice with regards to these options?

Thanks,

Frank

Hi Frank.

I have the Epoch Elite preamp. I've had a few volume controls in mine. I've currently got a 100k TKD Ko-on in mine. The main differences between that pot and a high quality attenuator is resolution and staging. The TKD loses nothing in bass extention.

The Ko-on does however seem to have a steep curve from 0 upwards.. This is no problem though, just different.

Partsconnection sell the TKD Ko-on's with a sheild between each taper, these are suggested to be the best ones to get.

Some more info here if you are interested in upgrades: http://theartofsound.net/forum/showthread.php?36363-Pushing-the-Croft-Epoch-Elite&highlight=pushing+epoch+elite

My pre certainly isn't warm and cuddly... :)

btw... the audionote pots are pretty poor in comparison to the TKD.

Hope that helps. :)

[mido]

Hi Frank.

I have the Epoch Elite preamp. I've had a few volume controls in mine. I've currently got a 100k TKD Ko-on in mine. The main differences between that pot and a high quality attenuator is resolution and staging. The TKD loses nothing in bass extention.

The Ko-on does however seem to have a steep curve from 0 upwards.. This is no problem though, just different.

Partsconnection sell the TKD Ko-on's with a sheild between each taper, these are suggested to be the best ones to get.

Some more info here if you are interested in upgrades: http://theartofsound.net/forum/showthread.php?36363-Pushing-the-Croft-Epoch-Elite&highlight=pushing+epoch+elite

My pre certainly isn't warm and cuddly... :)

btw... the audionote pots are pretty poor in comparison to the TKD.

Hope that helps. :)

Thanks for that, that is really very helpful. Sounds like the ko-on is the one to go for then.

[The Black Adder]

Nice one Frank.. :) It's a very good choice. Much better than the Alps Black Beauty (to my ears) - Next step up is a nice Attenuator... :)

[Haselsh1]

Regarding valves, I would only consider Genelec Gold Lion valves with gold pins from Hotrox or any other suitable supplier. I have tried so many modern valves and none come anywhere near.