Framus Cobra fizz?

[Metaltastic]

Hey guys, I was paying a visit to the new music store that just opened in my college town (Oneonta, NY); I was expecting your average assortment of knockoff starter guitars, which of course they had - but imagine my surprise when I walked in, looked in back, and saw a Framus Cobra head sitting in all its metal glory! Apparently they're a dealer, and after attempting to shove a sale down my throat, they let me plug in and crank up through a Budda 2x12 (they had the Cobra cab, but it wasn't out on the floor yet).

I had a fair amount of time to tweak the settings, and my thoughts were as follows: first, the notch switch on the Lead channel is nauseating; I can't ever imagine using it (it's like Master of Puppets mode). But also, it seemed to have an offensive amount of fizz that was operating in a frequency unaffected by turning down the presence and/or high knobs. What I'm wondering is whether the cab is to blame, or if this is an issue with these amps?

 

[Mood Bender]

the fizz goes away with a channel volume at 2:00 to 3:00 and higher.

 

[Seizure.]

Good to know.. i had the same problem!

 

[ochants76]

It needs to be loud.

 

[Where She Wept]

I played one thru a Marshall 4x12 w/g12t-75's and it sounded great.

 

[Erik Monsonis]

I don't like this amp at all.. WAY OVERRATED!

I completely disagree.

It just needs to be at 2 or 3 volume. And a nice 4x12 cab, especially it's one.

It sounds a little fizzy with v30s, it sounds better with v25 greenbacks.

 

[ochants76]

There is most likely a reason why the cobra cabs don't have v30s...(I think they good through v30s but there is a bit of fizz that isn't there with certain other speakers)

 

[cobrahead1030]

yeah, you need to crank the cobra pretty good before the fizz goes away...at lower volumes you'll need to have the treble and gain pretty high to get any kinda clarity and fullness with the amp, both of which bring in the fizz factor...as you turn the amp up, you'll wanna turn both of those knobs back down resulting in a much nicer tone

and yeah, those notch switches are pretty worthless IMO

 

[Tachy]

This amp is not fizzy at all.I set the bias at 29mV and with my mesa sts cab loaded with v30 it sounds awesome! the other guys tell you that you must crank the amp quite load....It's true, the cobra need to be cranked.....I don't use the notch switch, becouse I love the midrange of this amp.

 

[cobrahead1030]

the stock bias is another issue i forgot to mention...mine was kinda congested and fizzy sounding when i first got it, from the factory they're biased really cold which causes a lot of that

 

[ericwylde]

is 34 mA too hot for 6L6's?
i'll try some JJ 6L6GC in november

 

[Metaltastic]

Actually, if the cobra is anything like damn near all the amps Eurotubes lists in their "generic bias of a JCM800" section, 34 is a bit too cold...

 

[ericwylde]

i know 34 mA is only "medium hot" for an EL34 (i think they can run up to 40-45 mA), but i don't what setting would be too much for a 6L6

 

[cobrahead1030]

with the plate voltage of the cobra...around 30-35 is where you want it, they're usually around 20-25 stock!

 

[::XeS::]

Yeah, the cathode current depends on the plate voltage of the amp.

 

[Tachy]

Don't go with the cobra over 30mA..........

 

[ericwylde]

i e-mailed framus support and they said 30-50 mA will be fine for 6l6 tubes

 

[::XeS::]

Don't go with the cobra over 30mA..........

It depends from your plate voltage....every amp could have a different plate voltage...and with different PV you have a different cathode current.
Guitarhack for example, his Krank has a very high plate voltage compared to the average krank's PV..

 

[Tachy]

yes, but the cobra came with el34s, If you need to adjust the bias, don't go over 30mA with the el34s....I don't know about 6l6 tubes