Nailing this blackface champ tone

slowpilgrim

I love the tone of this 1965 champ from one of Johan's vids, and trying to understand what I'm hearing:

https://youtu.be/Krqic3DFlKo?t=151

From another vid, you can see that it has the original Oxford 8EV installed (not a Jensen like he indicates in the vid).

I have a silverface champ that has been serviced, with a P8R reissue that sounds great, but I cannot nail the tones from the vid. Despite having the same circuitry, it doesn't drive in the same way. Where that '66 sounds like it's all bloated and about to fall apart (which I love), mine has some of that low end squish at the same settings but doesn't squeal in the same way - it's much more controlled, harder, more meaty, and a lot cleaner.

I'm assuming this is just down to the 'crappy' speaker in that thing? The only other difference really is the smaller OT. I've read that blackface champs often sound 'browner' than the later ones. It seems odd as everyone talks about how bad the Oxford is, and if it's because it sounds like that^ then I guess I'm in the minority.

Any insight would be great - wondering whether I need to source an Oxford for mine, or consider selling up and investing in a blackface.

Winny_Pooh

It doesn't sound too nice IMO, speaker is farting out. There is a midrange mod where you can add a switcheable resistor off the tonestack to bump up gain which I recommend for your silverface. Its better than the negative feedback mod. 

brooom

Biggest problem with most champ is the way the output section is biased. My 65 vibrochamp sounded pretty thick with a strat when turned up to 6/7.

slowpilgrim

So you mean yours was biased correctly? Mine runs a b+ of around 395V or so which is pretty average for champs. 6V6 cathode is 23V.

brooom

I don't remember what the plate/cathode voltages were, the amp is back in portugal so I can't check.

 But I remember the cathode resistor was higher than most blackface vibrochamps and I don't think the plate voltage was that high either.

Modulus_Amps

In that video it looks/sounds like you are hearing the close mic and a room mic, both will have thier own tonal attributes.

In old amps components will have drifted up or down, that can make a big difference and as you have guessed the speaker makes a big difference too.

Also that is an old amp, so it may not be stock. 

CFH

Might a smooth cone speaker help? That often changes the character of the overdrive in a champ