ecl86 & ez80 - suitable for guitar amp?

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
ecl86 & ez80 - suitable for guitar amp?

Hi,

I'm thinking of buying a cheap old valve amp (combo) I've found in a shop with the idea of using it as a practice amp for guitar. It looks like some sort of old extension speaker for something or other (radio?) and contains 2 x ecl86 and 1 x ez80 valves. I've seen on the net that these are power amp valves and a rectifier valve respectively.

Would this work? would I need some sort of pre-amp stage?

Does anyone know what these valves would sound like, used for guitar? The combo has a small speaker with it which I know will affect the sound but I've no idea what the overall sound will be like. .... I can't seem to find any guitar amps on the net that use them (which suggests to me that there's a good reason for this!)

Also - from what I can gather, 2 x ecl86's would produce a max output of about 6W.... if I overdrive the amp, would this result in some nice sounds or something ghastly.

I don't know much about valves / amps / electrickery sorry, but any advice / info would be greatly appreciated

thanks
 
EZ80 = American 6V4 - you can also sub an EZ81/6CA4 in there.

ECL86 = American 6GW8. Nice tube, but scarce and getting more so all the time. It's a triode and a pentode in the same bottle.

I think it's almost impossible to tell you what kind of tone you'll have from the little we know about the amp, but the tubes in it are certainly capable of excellent performance. The EZ80/6V4 is fairly common, and if they dry up the EZ81/6CA4 will drop in. But the ECL86/6GW8 is going to prove difficult to source over the longer haul.
 
Hi greenstax,

the ECL86 compound valve contains a small signal triode which is identical to 1/2 of ECC83, and a small power pentode which for practical purposes could be viewed as a power derated EL84/6BQ5 (9 Watt of max. anode dissipation vs. 12 Watt).

Knowing this, you can chose from the plethora of guitar circuits using ECC83 and EL84, only very slight & simple bias adjustment (cathode resistor value) needed for the ECL86 pentode section.

In short, everything that works using ECC83 and EL84 (in pentode mode, screen voltage not above 250V) should be very easily transferable to ECL86, too :D

Regards,

Tom
 
...EL84....

How boring ;)

...Octal Fatness!!!....6V6, 6L6

Getting better, but still as common as beach sand.

Got a design on the bench now using an ECL86 to drive the IST iron to a pair of 6B4G's. It sounds great so far!

Be a heretic and don't follow the crowd, you'll be rewarded :)


You already have some of them -- and cryoed to boot

My dad has the headphone amp with the cryoed tubes. I think I'm in for a fight when I need it back :(
 
I didn't mean to be boring!:mad:

When picking projects for myself I often go for odd tubes that don't require much to work properly.
BUT ocassionally (how d'you spell that?) I pick simple designs with simple (and YESSSS! boring tubes) especially when I am looking for a special kind of result. If I wanna build a guitar amp I go for a simple and practical solution - the G5 or Octal Frumpness - I got all the tubes.
And having that kind of arguments, I'd say to Greenstax - use what you have!

It would be possible to make up a guitar practicing amp with 2C29A but that is TOO odd for such a piece.
 
Did I call *you* boring?

Maybe you didn't, but I know you thought I was boring. And that's even worse!!!!:mad:
(just joking)

I have avoided EL84:s myself, but have some 6N14P and similar and when I read about the tonal quality of the EL84 I see I must try something out.

I was for many years running a butchered Heathkit AA-32 with ECL86-PP and was surprised myself how good it was.
 
Ok then, I was getting worried! ;)

Actually, I just called that one boring because it's been done to death. But like the 6V6, it's hard to build a bad PP 15 watter, or SE-3 with it. Esp. for beginners.

6N14P sounds pretty cool. Closer to a 7189 than an EL84 though, IMO.

Cheers!
 
soundbrigade said:
But 6N14P IS SUPPOSED to BE an EL84.

Oh, it'll drop in and work of course, with little or no rebiasing. I didn't mean to imply it wouldn't. It just sounds closer to a 7189 than an EL84 (IMO, as I said. Which can differ greatly to the next dude's set of ears ;) )

EL86 I like to treat as a completely different animal. If you drop it in for an EL84, you'll probably have a dead tube and dead power supply.

Use 1/2 the amount of load Z on them, twice the peak current, less voltage and get a good 8-10 watts more than a pair of EL84 and they won't even work up a sweat :)

It's "Da T00b" for a practise bass rig :cool:
 
Here is that ECL86 Marshall.
Cheers,
Ian
 

Attachments

  • 1930.jpg
    1930.jpg
    52.1 KB · Views: 464
Hi,

Thank you everyone for all your advice / info / comments. This is my first post here, so really appreciate all the replies.

I managed to find that Marshall amp Ian - I think I may end up trying to clone it in some way, maybe without the Trem though.

In the words of Columbo...'oh and one last thing....'

As it stands, this amp that I'm thinking of purchasing (probably going to now based on all your help), has a power amp stage, trnsformer, volume and tone controls wired in etc ie, it's a complete circuit and should work in its own right.

Would it still work if I tried to use it as is? ie - would it work as a guitar amp without a preamp stage? Guitarists are always going on about how driving the power amp gets the best sounds so with this in mind, I was wondering if a pre-amp section was strictly neccessary?

Once again, sorry if this is all really basic stuff - I'm just trying to broaden my (admittedly poor) knowledge!

Thanks
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.