Modding my Tweed Twin

[Gunny47]

Hey dudes - I was thinking about modding my amp a little bit being that I was starting to get into modding my R7 (antiquities, tonepros bridge, getting RS caps and pots kit soon and other little things that are probably not true mods like 11 guage top wound strings, removing the pickguard and putting in a metal jack plate). First of all, I NEVER use the bright channel simply because it sounds like CRAP. It just seems to have this nasally tone or some wierd higher frequency noise in the background. Distorted tones are the same, but the clean tone is total garbage compared to the normal channel. So I was thinking of something that would "fix" my bright channel or just simply turn it into another normal channel or something of the such. Then, there is this terrible rattling noise when the amp is pushed up about half way on the volume. I don't think it is the cab, but it sounds like something on the chassis or tubes is f*cked up. And are there any other mods that are cool for tweed amps that wont stray too far away from the 50s style design and sound? Here would be an analogy - the TonePros Bridge on a 50s Les Paul. It has that "better than vintage vibe" but it is not like "high gain modern metal vibe." Something that is like better than vintage that will maybe limit the hum on the amp, I have no idea, I'll leave it pretty much open. Most likely I'll just put in some new tubes (the three 12AY7s to give me the lower gain, sweeter sound, a JJ 12AX7 to smooth out some of the highs and the tung sol reissue 5881s) and leave it alone, but I am still curious as to what is out there and where I can send it to. Alright guys, thanks and Fire AWAY!

 

[the guy who invented fire]

Re: Modding my Tweed Twin

In reguards to the rattle...what kinds of rattle is it and what kind of 6L6's are you using??

 

[Gunny47]

Re: Modding my Tweed Twin

It's all stock glass in there. I had a NOS blackplace RCA 12AX7 in the phase inverter (4th preamp, I guess you can call it phase inverter because thats sorta what it does) but I just wound up putting that tube into my Gibson and put the stock groove tubes 12AX7 in there. So yea, all stock Groove Tubes (the power amp tubes are the recent Groove 6L6GEs which are supposed to be - from the Groove site - a faithful reproduction of the original General Electric "clear top" tube made on the original GE machines and with many original materials).

The rattle sounds metallic and not as much wood cab-hitting-chassis, but more like, coming from the tubes or something. I gotta fool around with it and see if a tube is a little loose...

 

[the guy who invented fire]

Re: Modding my Tweed Twin

Ok, on the mod end I strongly suggest keeping out of your amp for several reasons but swapping tubes can be a great way to get more different tones...try all kinds and brands of 12A_7 tubes in all different sections.

On to the rattle...I can't hear it from here but I am gonna put money on the power tubes...I have had nothing but problems with current production 6L6's having a metallic rattle to them. So far I have had decent luck with the Winged C SED 6L6's also hear good things about the reissue Tung Sol but I have not tried them...My Super rattled when i got it and I drove myself nuts looking for the rattle...turned out to be the TAD 6L6's...after a swap to some NOS JAN Phillips...no more rattle, however thats an expensive fix!

 

[Gearjoneser]

Re: Modding my Tweed Twin

To troubleshoot the rattle, tie some shoelaces around the 2 power tubes, turn it on and play loud. See if the rattling is still there and take the shoestrings off.
If that was the problem, you can either buy tube dampers on Ebay, which are rubber bands that won't burn. Or, you can even put a stripe of silicon glue on the sides of the tubes. I learned that trick from a tube amp guru, so it's safe.

 

[Hot _Grits]

Re: Modding my Tweed Twin

Get yourself a patch cable and jumper the bright and normal channels together. Then use the two volumes together to dial in different shades. You might find some cool tones that way.

Also find out if your amp can take different rectifiers and play with them. Try a plug-in solid state rectifier and see if you like that. It'll push the amp more towards a marshall feel.

 

[ES350]

Re: Modding my Tweed Twin

Clip the 100 pF bright cap from the bright channel, stuff a 12AX7 in one channel, a 12AY7 in the other---two gain levels. Alternately, you can sub in a lower value bright cap--27 pf, 47, 68, etc. If you look at the treble pot, there is a 47 pF cap across the wiper---it's always there, and that accounts for some of the bright in these amps. Even the originals sound a little brighter than other tweeds from that era. You could snip that out too...BTW, that rattle is probably those 'premium' GT tubes...Try some Winged C power tubes.

 

[jeremy]

Re: Modding my Tweed Twin

another vote for power tube rattle

you dont jump the channels already? i barely touch my bigger tweed amps if they arent jumped. i prefer the non-jumped tweed dlx but the bassman and bandmaster are always jumped.

the 12ay7's will help, 6072 are low noise 12ay7's. i like em in v1 and v2.

 

[Gunny47]

Re: Modding my Tweed Twin

Ive got a small patch cable, but aparently you cant jumper the channels like you would on a normal 4 input bassman or plexi or JTM45 type amp. Ive tried it, it doesnt do anything. You need a y cable with 2 male ends and one female end and I aparently just never got around to buying one.

I've got no money now because I just had some work done on my R7, so once I get some more cash I'll try new tubes. I am going for current production to keep the price down, so do you guys recomend any or know of any current production 6072s? Thanks. If not, Ill just wind up with either the Tung Sols or Winged Cs in the power section and electro harmonix 12AY7s in the preamp.

And ES350 - what do you mean by "clip" the bright cap? I know nothing about this type of stuff, so do you literally mean to use wirecutters and cut it out (dont worry, Im not touching anything yet, and do not know the layout of the inside of the amp at all really). Chances are, I'll bring the thing to a tech to get the amp biased and cleaned up and checked out a little bit. So does anyone know of any amp repair places in the New York City area where I can bring my amp (I know Rudys doesnt do amp repairs and either does guitar center - I wouldnt trust them with it anyway). So just throw out some good known Fender authorized dealers that are good with amps please if anyone knows. Thanks a lot guys!

 

[jeremy]

Re: Modding my Tweed Twin

have you tried jumping the channels? plug into bright 1, run the jumper from bright 2 into normal 1. im curious what happens

 

[Gunny47]

Re: Modding my Tweed Twin

Yes I've tried many times and In pretty much all combinations (plugging into bright 2, and both normal inputs) and all it sounds like is the normal signal, but its a little quieter and you also hear this noise (similar to the noise you get when the amp is on and a cable plugged into it and you are about to plug that cable into the guitar (just that hum, not the real loud noise you hear when the cable just touches the input jack of the guitar). The other volume knob (of the channel you are not plugged into) just raises the loudness of the noise or hiss. All the way down still yields the hiss.

I gotta get this:
http://www.hosatech.com/hosa/products/ypp-106.html
And thats how you jump the channels on the amp

 

[ES350]

Re: Modding my Tweed Twin

I can jump the channels in my '56---but you need the y cable. All four inputs are seperate triode sections and not bridged internally (notice 4 preamp tubes instead of the usual 3 on most tweed models?). Anyway, the 47 pF bright cap is across the treble wiper (on the RI layout, C8 IIRC) and Fender only did this on the the 5E8A, maybe the 5E6. To me, it seems a little too much and gives the amp a brighter tone than the other fencepost models or even most of the F series tweeds. Fender ditched it after a year or two and it doesn't show up again in any Fender amps. It would probably void your warranty to get it removed, but with 2 new P12Q's, I could see it being a tad crispy.

 

[drew_half_empty]

Re: Modding my Tweed Twin

get the Y cable & see how you like it

if you still find the bright channel unusable, go in, clip that cap, and put something like a long bottle jj gold pin in that slot, or maybe a 12at7

 

[OlinMusic]

Re: Modding my Tweed Twin

I think you should have it modded to have a super high gain channel and then a second gain channel for the first one to cascade into

Gain for days.

Change the speakers to EV's, and then find a new chiropractor.