Tweed 5F4 Super - Tone for Days - No clean?

[beckspeed]

Yep I have a tube screamer that gives it a pretty good crunch - especially with volume on 2-6 range - distortion starts to get "loose" after that.

I'd like to be able to clean it up with the guitar volume but it's almost impossible above 7 - guitar volume pot is almost off.

Could this be the amp volume control? Wrong cap on there? Merging two vol into 1?

Thanks

[Ed_Chambley]

No way for me to know. I would take the 5f4 schematic and verify each component and mark both, parts and schematic. If you run across something different, change it. Once you have all the schematic noted, what is left is what the builder did to mod. Not a good amp to mod, so I recommended stock.


I also recommed a choke input due to the voltage drop difference. To me, the choke input does make a difference. It changes the power section voltage a lot. Ig is like you have a 5f4 preamp and a bassman amp.


Or rework the amp to a 5f6a. Not hard to do since you have the correct iron for it.


Other than this, the stock 5f4 is not one of the tweeds most folks prefer. Thd 5f6a is.

[shooter]

Did you ever try SG's suggestion of AY in V1.  I use AU on most builds in V1, lower gain, less noise-usually.

otherwise like Ed says, find out what ain't supposed to be there and go from there

without a scope it's hard to tell where you're getting the bad stuff

[beckspeed]

Thanks Ed - that's basically what I did last night - I traced every connection and component, noting the differences on the diagram below (stock mojotone on top). It doesn't sound like there is anything vastly different or out of sorts. I'm just trying to determine where I need to start changing stuff.

my main areas of concern:
1) the eliminated "bright" volume control
2) addition of 47pf cap to normal volume
4) 4.7k resistor in bias section vs 6.8
5) elimination of Presence control

Shooter! I was just looking at tube options - that could be a great quick fix to test a 12ay7 - would it go in the middle preamp spot?

Thanks as always!

[beckspeed]

Now I see! After crawling through and Tracing every component in the amp I see that I missed the most obvious change, having a 12aX7 in v1. I know you guys mentioned it but it didn't register. Will try 12ay7 tomorrow.

[beckspeed]

Well hot damn. I tossed a 12ay7 in V1 and it solved about 75% of the loose distortion issue, but couldn't quite get "clean" at 10 without turning the guitar to off. So I figured I'd keep going and tossed a 12at7 in V2 and it made all the difference. a much more controllable growl at full blast, but I can clean it up with the guitar volume. If I need a little extra the TS808 gets it well into marshall territory.

One question - is the 12at7 in V2 going to cause any issues?

Sluckey, shooter, Ed, HotBluePlates - Thanks for all the help. Maybe I'll listen and try the easy way next time?

Thanks again.

[shooter]

So I figured I'd keep going and

try an AU in V1 also, it has less gain than either AY or AT.  You can also do some reading, googlin, on voltage dividers to knock some of the gain with R's before the "next" stage.  I'm no wiz on that amp, but I think you want to leave V2 an AX, but it is easier to change a tube than un-re-solder R's

[beckspeed]

Shooter - you were right. I put the 12AX7 back in V2 and swapped a 12AU7 into V1 and it's even better than yesterday. It's still got plenty of growl but I can roll off the volume or go gentle with the pick and it cleans WAY up.

Thank you!

[shooter]

you were right

just like a broke clock
now you're qualified, go build

[beckspeed]

Update to an ancient thread!

So after almost 2 years of fighting this amp, I went back through this thread and through the amp and decided to take major action.

The amp was a source of many small annoyances. Mostly burning out #1 preamp tubes and all-around inconsistency. The controls were all over the place, changing either volume, treble or bass would radically change the sound, I was constantly fiddling with knobs.

SO. I was going to go one of 2 ways: change the circuit to something like a low-power twin/ bassman OR change the iron to the correct components.

After digging into it I determined that the only components needing to be replaced were the OT and the Choke - and it only cost me about $100.

After about an hour of work yesterday its like a whole new amp! The controls are MUCH smoother the volume mostly just makes the amp louder (a novel idea) and Treble and Bass do what they're supposed to do. The amp stays clean through 7 or so on the volume and then begins to really overdrive, I can actually clean it up with the guitar volume though, somehting that did not work well previously. Also the wierd "mid" control works now too, not exactly like a mid but not like gain either. Useable none-the-less.

SO long story long - Thanks Ed_Chambley, shooter, SILVERGUN, sluckey, HotBluePlates for all of your great insights and help!

[shooter]

so what tube type did you settle on for V1

[beckspeed]

12AY7 - was trying to get everything as close to baseline as possible. Works great.

[Ed_Chambley]

I am glad you found the Super 5F4.  Like I mentioned, lots of people do not like this amp, but it was THE amp guitar to many old great players.  Oddly enough, this 22 watt monster in original form (I really do not know the wattage) did play clean to today's standards, however the sales were driven by the overdriven tone.


You can even hear Billy Bird overdriving one on some Ernest Tubb records.  Probably has something to do with Texas.  I have never met anyone from Texas who doesn't appreciate beathing the hell out of power tubes.  Just ask Dummyload.

[beckspeed]

Well dang - and now you've hooked me on Ernest Tubb and Billy Bird!

any recommendations - ET's discography is huge.

Thanks!

[Ed_Chambley]

Well dang - and now you've hooked me on Ernest Tubb and Billy Bird!

any recommendations - ET's discography is huge.

Thanks!

Very true, actually Billy Bird was a very accomplished Jazz player and adde3d the swing sound to ET's Honky Tonk sound.  Ernest released a Box Set of 6 CD's in 1999 that has him singing all the old hits and new ones as well.  I have always thought he kept a top notch band, just like Bob Wills and his player Eldon Shamblin.  Eldon played the very first Stratocaster and the first offset fender too.  He and Bob we friends of Leo Fender.  I have seen a lot of photos of Eldon with a Strat plugged into a tweed super.


These guys playing western swing never really got any acclaim as musicians.  Before I got into Western Swing, I used to think it was easy.  Then I had to learn Faded Love to play live.  Then I understood.


I hope you are having fun, it sure sounds like it.