ShortScale.org

James wrote:I call beret guy, which I'm afraid makes you the less cool ginger guy. Euan to be Kari? I'll get working on the goatee.

As a big fan of Mythbusters, I approve this comment.

im thinking hilary has to be kari right?

So I got it home last night finally in a house with a step down transformer - and it's ace. Really lovely cleans and a healthy amount of bass for such a small amp and speaker.

Doesn't sound all that hot when you boost it into too much front end overdrive but that's not really the point, it sounds pretty Mega as a clean amp all the way up the Volume dial and takes pedals really well, so it's exactly what I needed. Job Done.

Sweeeeeeeeeet, I was waiting for good news!

It's very pretty also, the grill cloth is spangly and I like the jewel light. I'll bring it to Progfest innit.

The guy had all the original documentation, like the manual (What does the Volume knob do? LEL) and the schematic that was provided with the amp - very cool. For £300 I'm very happy, it's in pretty much mint condition. Expect to hear it on the new Sell Crazy record.

Mine has way too little bass, and the bass knob has nearly no effect. May this be because the speaker was swapped to a current-series-Jensen at some point? Or is it rather because yours has that transformer?

Rock ass! Are you planning to replace the input transformer with a UK voltage one?

Nah, I'm just going to leave it as is, since I bought the step down transformer, and it's not large or anything. It's fine by me.

Kyp - you can really tell when you roll the bass off mine, it goes really tinny. My '66 Jaguar is a bright beast but it still sounds full and chunky if I have the Treble on around 3 and the Bass up full. When you put an overdrive like a DLS or an OCD in front it has bags of low-end thump.

My old/new Vibrochamp could be really bassy - used to play the baritone through it, even. Nice one Mike.

wow. My Champ is more like, very thin from 0-5 on the bass knob, then you notice something changing between 6 and 10, but it's still rather thin. It's more like a very weak on/off-effect. Haven't found any other flaws though, so ill blame the replacement speaker for the moment.

As I said, what's great about it is that it is loud enough for small gigs, not boxy at all (different from many current amps that are this size) and super natural, or if you want so, precise. You can really hear it if you use a different guitar or pickup or a cheap or good pedal. But still the Champ has his own character. It's vivid and sparkling.

Congrats to a bassy Champ.

Cheers!

Only shame is the lack of speaker output jack for funtimes with cabinets, but since it's expecting a 3.2 ohm load that would be limited anyway, plus it's meant to be for low-volume shizzle in my Hackney pad, so it's all good. Overall I'm very happy.

Nice one, congrats!

Is it loud enough to piss of your neighbours?

ANY Amp is loud enough to piss the neighbours (if they live wall to wall with you, of course).

SirAstatine wrote:Nice one, congrats!

Is it loud enough to piss of your neighbours?

I would say anything past 7 is Anti-Social if you're living in a Flat, Terraced House or Semi Detached House.

Shit photos are shit

kypdurron wrote:wow. My Champ is more like, very thin from 0-5 on the bass knob, then you notice something changing between 6 and 10, but it's still rather thin. It's more like a very weak on/off-effect. Haven't found any other flaws though, so ill blame the replacement speaker for the moment.

As I said, what's great about it is that it is loud enough for small gigs, not boxy at all (different from many current amps that are this size) and super natural, or if you want so, precise. You can really hear it if you use a different guitar or pickup or a cheap or good pedal. But still the Champ has his own character. It's vivid and sparkling.

Congrats to a bassy Champ.

Have you tried replacing the rectifier tube with a 5U4 or GZ34? They apparently will give you more output and bass.

Mike wrote:

SirAstatine wrote:Nice one, congrats!

Is it loud enough to piss of your neighbours?

I would say anything past 7 is Anti-Social if you're living in a Flat, Terraced House or Semi Detached House.

That's pretty good - can get some range out of it. Better that it can get up to sort of cooking levels without being offensive.

Looks sweet too - nice one.

Have you tried replacing the rectifier tube with a 5U4 or GZ34? They apparently will give you more output and bass.

Careful with those rectifiers. In the old tube manuals the 5u4 looks pretty similar to a 5y3 for voltage drop (50 or 60 volts). The 5u4 is not being worked as hard so it will not produce a high enough voltage drop. These silver face amps run the tubes pretty hard to begin with, so your B+ might jump a few extra volts. Add to that the fact that 117V was the standard in those days. Your "today" voltage might be a bit over 120vac (after conversion of course). The B+ starts to run a bit wild. If you look at the schematics for the AA764 (Black face) and the AB764 (Silver face), the big difference is the first filter capacitor in the power supply. I'm sure it is the same Mallory capacitor. All they have done is tied two tabs together to get 40uf. Where as on the AA764 they only use the one tab for 20uf. Under the 40ma or so load of the Champ circuit, it would drop the voltage 30 or 40 by only using one tab. I havn't modelled it so I'm just guessing. I'm sure the GZ34 has a very low voltage drop in comparison.

Interesting stuff, thanks for the input. I was under the impression the circuit was the same in the Champ for both Blackface and Silverface versions.

Mike wrote: Have you tried replacing the rectifier tube with a 5U4 or GZ34? They apparently will give you more output and bass.

I really did like that, for some reason I changed the type. Dunno which for what though, will look tonight.