wrong el84s?

[bobbyr]

I recently changed two tubes in my wem dominator amp.
I replaced two mullard el84s with two sovtek el84/6bq5 tubes.
Now the amp doesn't sound very good and the volume is very low.
Does anyone know a suitable alternative to put in as it's to expensive
to put mullards back in.

[zaphod_phil]

Sovteks won't sound anywhere near as good as Mullards! However, their volume level should be about the same - so I don't understand what's going on there. Watford Valves' Harma STR EL84s are a fantastic alternative for Mullards and at a pretty reasonable price. I believe they're actually NOS Tesla Roznovs, which Watford burn-in tests and relables. So you could also buy the same valves probably a bit cheaper from Sgt Overdrive, who often posts on this BBS, if you don't mind waiting for a shipment to arrive from the USA - terry@bhs1983.com

You may find this recent comparative test review by Watford helpful in chosing other suitable alternatives to Mullards:
http://www.watfordvalves.com/cgi-bin/do ... ort_47.pdf

[Rafael]

Hello, 1st poster here...

Are Teslas a good option? I mean JJ Teslas, the new ones.

thanks

[jockman]

Sovteks won't sound anywhere near as good as Mullards! However, their volume level should be about the same - so I don't understand what's going on there. Watford Valves' Harma STR EL84s are a fantastic alternative for Mullards and at a pretty reasonable price. I believe they're actually NOS Tesla Roznovs, which Watford burn-in tests and relables. So you could also buy the same valves probably a bit cheaper from Sgt Overdrive, who often posts on this BBS, if you don't mind waiting for a shipment to arrive from the USA - terry@bhs1983.com

You may find this recent comparative test review by Watford helpful in chosing other suitable alternatives to Mullards:
http://www.watfordvalves.com/cgi-bin/do ... ort_47.pdf

+1

[bobbyr]

Thanks for the replies. Maybe someone could shed some light on this: when I put the old mullards back in the volume comes back but the sound is breaking up a bit. Is it possible that there are two types of el84's, high power and lower power or are all el84s the same power wise?

Maybe I am barking up the wrong tree. Could it be the preamp valves that need replaced instead. I defo need a new el84 now anyway as the old one has just broken when I took it out doh!

Thanks again for all the help as you can appreciate I am a newbie at this valve replacement stuff

[zaphod_phil]

Are Teslas a good option? I mean JJ Teslas, the new ones.

Nicer then Sovteks, but nearly as good as old style Teslas. The article I refered to earlier provides a very good overview, http://www.watfordvalves.com/cgi-bin/do ... ort_47.pdf

...when I put the old mullards back in the volume comes back but the sound is breaking up a bit. Is it possible that there are two types of el84's, high power and lower power or are all el84s the same power wise?

In that kind of amp the sound is definately meant to break up quite a lot! I'm wondering if those Sovteks aren't from a batch that has a very low gain, or are just faulty in some way.

Maybe I am barking up the wrong tree. Could it be the preamp valves that need replaced instead.

Your preamp valves are unlikely to need replacing. Mullard ECC83s go on for years and years.

[bobbyr]

I have just ordered two NOS Mullards.It should sort out the problem and keep the amp original.
They weren't cheap but I think I would miss the tone of Mullards anyway.
Again thanks for the help.

[zaphod_phil]

I see your point. If you don't mind my asking, how much did you pay for the Mullards?

[bobbyr]

£30 each

[zaphod_phil]

That's quite reasonable for Mullards.