Replacing Valve in my Eden head

[Randy_Marsh]

I've never done this before and was wondering which valve would be the best to replace the current one with. Iv heard good things about the Electro Harmonix 12AX7, but was wondering what people would recommend...

[voxpop]

Hi,
The 12ax7 is the same as a ECC83,both these valves have a gain of 100. If you want to lower the gain to give a cleaner signal with more head room try a ECC81 or 12at7 as a replacement.


Shameless plug for valves for sale......

[url="http://basschat.co.uk/index.php?showtopic=98555"]http://basschat.co.uk/index.php?showtopic=98555[/url]


Sorry....

[mazdah]

Try some Goove Tubes - very fat and round sounding. Or JJ ECC83S - clean and well ballanced.

And don't bother with Sovtek 12AX7WA, I had them on my 3pro and they were no good.

Edited August 24, 2010 by mazdah

[Randy_Marsh]

I'm stuck between the ECC81 and ECC83-S. What would be the main difference in these tubes?

[voxpop]

[quote name='Randy_Marsh' post='935791' date='Aug 25 2010, 11:30 AM']I'm stuck between the ECC81 and ECC83-S. What would be the main difference in these tubes?[/quote]



I have used both ECC83 and ECC81 as a preamp tube and find the lower gain ECC81 to be a good choice to tame down a high gain preamp stage that over drives or distorts. I prefer a clean sound so this would be my personal choice. BUT if you prefer the higher gain and crunch I would stick to the ECC83.

Get both and try them out, this what I did.

I also tried a ECC82 which has only 20% of the gain. This produced the cleanest sound of all but might reduce the volume to much. I have not tried it in an Eden. Might be worth a go as well.

Edited August 25, 2010 by voxpop

[voxpop]

[quote name='mazdah' post='935027' date='Aug 24 2010, 05:17 PM']Try some Goove Tubes - very fat and round sounding. Or JJ ECC83S - clean and well ballanced.

And don't bother with Sovtek 12AX7WA, I had them on my 3pro and they were no good.[/quote]



The JJ is a very good preamp valve, best of the three.

[GarethFlatlands]

JJs are the Matamp valve of choice, they're in my GT1 head and I can recommend them, although my knowledge of tubes isn't vast.

NOS Mullard if you can get your hands on one?

[bumnote]

I am not a techie but when I posed the same question about mine some years ago I was told that because of the design of the eden amp, the choice of preamp valve makes no audible difference.

Certainly the substitution of the existing for a boogie one made no difference

[umph]

[quote name='Randy_Marsh' post='935791' date='Aug 25 2010, 11:30 AM']I'm stuck between the ECC81 and ECC83-S. What would be the main difference in these tubes?[/quote]
83 has more gain and higher plate resistance 81 has less and lower plate resistance.

The lower the plate resistance the higher the high pass filter it forms. So you may notice a little bass loss with an 81 or 82 depending on the circuit

Edited August 28, 2010 by umph