NAD: Splawn Super Comp - Some Questions

[peckhart]

So I took delivery of a used Super Comp Mini last week.
I haven't played it a ton, but first impressions are it's a pretty cool amp...I've had Quickrods before and this has the Splawn thing I dig for sure. I used it at practice this week, but through a shitty cab at my singers house.
Although only low volumes so far it was much nicer through my Bogner cabs.
The interesting thing I am trying to figure out is the Mode and Overdrive selections. With Mode selected the mid shift up is very obvious. The Overdrive less so and what is weird is that when I have Mode on and OD1 on it drives it into immediate squealing feedback with the gain over like 11:00. Even at low volume. It seems like the OD is more than just a gain level increase.
Not too big of a deal as I can dial back the gain and kill it, but it does make me wonder if it is working right. And I did drop all new tubes in it.
Any way I wanted this amp for a more portable back up and smaller amp for grab and go scenarios. I can and probably will use it as the main amp on some gigs just for a change of pace.

 

[311boogieman]

Congrats on your amp.
Not sure what to say.
Seems odd. Free bump.
Maybe call Scott.

 

[stratjacket]

Congrats on the amp. Can't help with your question, but would love to hear more thoughts on it. I've eyeballed these amps for a long time and there isn't much info on them. It supposed to be the OD channel of the Nitro, correct?

 

[peckhart]

Congrats on the amp. Can't help with your question, but would love to hear more thoughts on it. I've eyeballed these amps for a long time and there isn't much info on them. It supposed to be the OD channel of the Nitro, correct?

That's my understanding and the Mode pushes the mids up a bit to be more like the QR.

 

[311boogieman]

'Driving to immediate feedback' screams bad preamp tube to me.
But you've already replaced all the tubes.
I'd swap a known good preamp tube through each slot anyway.
I'd clean the sockets by spraying tube pins with electronics contact cleaner.
Generally move some preamp tubes around and write down noticeable differences.
Pull all the preamp tubes, minus the Phase Inverter, and see what happens
Don't take the last preamp tube (Phase Inverter) out.
Plug guitar into FX return and tell us what happens.
--------
Usually after this point I would direct someone to a tech.
Could be a bad solder joint, trace, socket, etc.
Also might be possible the footswitch has a bork in it.



Edit: I'm not an amp tech and I've never built an amp.

 

[ericb]

So I took delivery of a used Super Comp Mini last week.
I haven't played it a ton, but first impressions are it's a pretty cool amp...I've had Quickrods before and this has the Splawn thing I dig for sure. I used it at practice this week, but through a shitty cab at my singers house.
Although only low volumes so far it was much nicer through my Bogner cabs.
The interesting thing I am trying to figure out is the Mode and Overdrive selections. With Mode selected the mid shift up is very obvious. The Overdrive less so and what is weird is that when I have Mode on and OD1 on it drives it into immediate squealing feedback with the gain over like 11:00. Even at low volume. It seems like the OD is more than just a gain level increase.
Not too big of a deal as I can dial back the gain and kill it, but it does make me wonder if it is working right. And I did drop all new tubes in it.
Any way I wanted this amp for a more portable back up and smaller amp for grab and go scenarios. I can and probably will use it as the main amp on some gigs just for a change of pace.

I have a 50 watt SuperComp head and love it. There's NO "immediate feedback' on mine with any of my guitars, or at any volume, so sounds to me like you have a very microphonic preamp tube, really bad pickups in your guitar (which I highly doubt!) , and /or another problem... .

I assume you're using the 3 button footswitch? I have a 4 button for my Streetrod but only 3 button for Supercomp as that's all mine takes. The mode is the "Nitro voicing vs QR voicing" basically, and the OD1/OD2 are not very different from each other at all. .Just different shades of od. .

Good luck! Eric

p.s. EDIT just noticed you said "Super Comp MINI" and I've never heard of the MINI.. . . so I don't know if it's similar to my regular Supercomp or not!

 

[peckhart]

So I got to play this amp for a while today at higher volumes and connected to my live rig. I was not having the strange feedback issues. I am not sure if it was just some whacky settings before or if maybe the Power tubes cleared it up. I changed the preamp tubes first and it still did it, but now I can't recall if I noticed it or even tried to drive the gain pretty high on OD1.
At any rate I had it cranking with all levels of gain and all Mode/OD combinations without issue.

I think I am going to call this thing 'Little Thunder', cuz man does it bring it. It is a pretty cool amp for sure. Seems a bit easier to dial in the high end on this compared to the Quickrods I had. The Treble doesn't suck all the thickness out when you use it. Gotta be careful with the bass and Resonance or it gets out of control quick. It is definitely easier to manage as a backup head to take to gigs. Could stand to be just a little bit lighter, but I'll take the punch this thing packs in the smaller footprint as a fair trade off.

And as far as I know, this Mini version is the regular Super Comp, just in a small head shell and probably a condensed chassis to fit that shell. Circuit and components are the same.