Can I get the enough clean volume(headroom) with EL84 pair?

[vibratoking]

I wrote a long post, but the forum software glitched and it is lost. Here is the short version.

I have a Mesa Lonestar Special with 5/15/30W settings and 4 EL84s. The 30W mode is the only one that can get even close to having strong cleans with enough volume to get over a drummer. I find myself always needing a bit more. I think you need 50W to do what you want to do.

[shane]

If you want to increase the amount of input signal you need to drive them you can try running them in UL. And yes EL 84s sound fine In UK.
This can often increase the required bias voltage. Fixed bias would probably help too.
But even the 18w has its limits!
More speakers means more SPL, and bigger iron more freq response, still think you'll need more valves or bigger ones for what you want, but its worth a try!

[martin manning]

A small footprint is aparrently a high priority here. Running a pair of EL84 with plates and screens at 400V theoretically produces about 34W, driving Vg1 to zero, and a 70% of Pa max bias point will require about -19V. Fixed bias is definitely the way to go.

[TUBEDUDE]

You mean a quad, right?

[martin manning]

No that is for a pair, but that's load line power. For comparison, 6V6's will do about the same. A Deluxe Reverb running at 400V on the plates is called a 22W amp, and most would agree that a DR is not enough power to play with a loud drummer. It has a vacuum rectifier, however, and the power will drop like the square of the voltage sag (10% voltage sag = 20% reduction in power).

[TUBEDUDE]

Wow, 34W from 2 skinny bottle EL's. That sounds like a hand grenade with the pin ready to fall out. Can those tubes under those conditions possibly last long enough to be a viable design goal? I would worry about my Telefunkens, or even my Sylvania 7189A pair.

[martin manning]

Read through the thread linked above. At the end there is a report- no issues after a year of regular use running plates at 430V. That increases the load line power to 40W!

[67plexi]

The Russians made a EL84 that could take 450 volts max on the plates
but are hard to find now. You may like the JJ-6V6-S nice cleans.
Most of the new production EL84 Quad guitar amps I have serviced are running 340-360 volts on the plates. Not enough volume to over power our loud drummer with no microphone. That said I'm back to 100 watt amps.
Volume 2 Master Volume 2 just right.

[tubeswell]

The Russians made a EL84 that could take 450 volts max on the plates
..

http://www.siberian-shop.com/6p14p-7189 ... l?cPath=65

[Colossal]

The Russians made a EL84 that could take 450 volts max on the plates
..

http://www.siberian-shop.com/6p14p-7189 ... l?cPath=65

I have a couple of quads of these left. I have used them for Rocket builds and they sound really good. Very rugged.

[JMFahey]

IF you are short of chassis space but can accomodate a couple 6V6, then a couple E34 need about the same.
They are taller buy anyway iron plus breathing space will dictate minimum height above chassis so no real loss.
2 big bottles (6L6/EL34) plus a single 12" speaker combo is a tried and true stage workhorse, which will NOT struggle to do its thing.
A smaller amp will work in some cases but will be on the edge most/all the time if paired with a drummer, the only constant in this acoustic equation.

Or :you can pack and transport 1000 pounds of sand in a Toyota Corolla or a Ford F100 ; which one will do the job better, faster, for longer time?

[Andy Le Blanc]

Put a mic on it and crank it in the monitors...

small envelopes have voltage restrictions, and longevity issues if you really push them.
I've had many el84 rigs thru for repair by players trying to keep up with crappy drummers at too many bar gigs.

I do like a smaller amps because you can crank em and make them sing the way a tube amp can.

but clean head room has always required mo watts...

you can run 4x 6v6 on the same iron as 2x 6l6 and get the benefit of 6v6 tone with a similar watts... but you do need to mind the MAX conditions published for the device

Another approach is to maximize the amps voice for the watts that you do have.

a stiffer power supply is mentioned

you can also limit the bottom end of the rig critically with the power side coupling caps, focus the response.

you can also mind the screen grid voltage relative to the plates, give the screens a power tap that you can control and set up mindfully.

and speaker efficiency can really make a difference...