Hartke HA5500

[phil_the_bassist]

Mornin Gals&Gents!

So, I've got the HA5500 with the hybrid Solid State/Valve preamp, and I've never really paid it much attn as I couldn't really notice much of a difference when dialling in the valve section...so I just leave both dials at 1 o'clock and have at it.

Is there any way to swap out the valve with something a bit ballsier (wow, the spellcheck didn't fire off! Ballsier is a REAL WORD!! )? I'm not expecting a TE V8 or SVT tone, but if you guys think theres a way to get a bit of tube growl then I'm willing to give it a shot

Whatcha recon?

[peted]

I think that you might have to somehow change the voltage or current going to the valve to get it to distort but I'm not expert! Perhaps there's a valve that is naturally a higher gain which will overdrive without any mods to the amp itself.

I swapped the stock Sovtek which came with my Hartke 3500 out for a Groove Tubes Mullard and can at least tell you that there is no tube growl, but the sound is lovely and clean.

[Mr. Foxen]

EHX valves are gainy and grindy.

[Badass]

[quote name='Mr. Foxen' post='529470' date='Jul 1 2009, 12:06 PM']EHX valves are gainy and grindy.[/quote]

Really would like to try this out on my 3500, just to see how it affects things. Anyone know what the valve is? A 12AX7?

So a EHX equivalent would be? Can any damage be done when changing preamp valves like this?

Thanks and sorry for the hijack

[phil_the_bassist]

No worries, Mr Hijack

Thanks for the tips guys, I'd also like to know the answers to Badass' ?tions

[cheddatom]

I don't know the answers to your questions sorry but..

Have you tried overdriving it by boosting the input, with an EQ pedal or a boost pedal?

Would putting a higher gain input valve in risk overdriving the poweramp?

[Jase]

I had a chat with these chaps:[url="http://www.watfordvalves.com/"]Watford Valves[/url] when I changed the valve in my LH-500. 12ax7's IIRC.

[Musky]

I was about to point you at Brycebites very handy [url="http://basschat.co.uk/index.php?showtopic=42"]Preamp Valve Comparison[/url] thread, which was a sticky at one point. Obviously it's not as useful as it once was, but there's probably still some useful info there before you need to look elsewhere. If I remember rightly he was at the time using a Hartke as his test bed.

[Jase]

[quote name='Musky' post='529916' date='Jul 1 2009, 08:15 PM']I was about to point you at Brycebites very handy [url="http://basschat.co.uk/index.php?showtopic=42"]Preamp Valve Comparison[/url] thread, which was a sticky at one point. Obviously it's not as useful as it once was, but there's probably still some useful info there before you need to look elsewhere. If I remember rightly he was at the time using a Hartke as his test bed.[/quote]

+1

[Buzz]

Another +1 for Bryceee's Preamp valve thread. Good bit of information that is. Finnbass has the maintained version on it (like said in Bryceee's BC post).

You'll probably want to stick with a 12AX7 (ECC83) for it's gain factor of 100.

Edited July 2, 2009 by Buzz