How to soften the 'attack' of tube amp?

[Chuck H]

Yup...

Keep your iron clean by wiping it on a damp sponge. If you have any trouble getting a joint to melt try hitting it with a little fresh solder. The idea is to work clean and spend as little time as possible with the iron on the joint and still get good melt and fluxing. I mention these things because those non adjustable irons are typically hotter than needed and you don't want to damage anything. But I have done many mods with a cheap iron and they work fine.

Chuck

[bhuether]

Thanks for all the great tips. Where do you think I should order the parts? Are there particular capacitor brands that are preferable?

thanks,

brian

[Chuck H]

I use Sprague 715p's and Mallory 150's. But you aren't replacing enough caps for it to matter. You probably wouldn't hear much difference whatever cap you use. But FWIW I like to use polypropylene where I can because it is more temperature stable. So my amps don't sound different between turn on and the third set But polyester caps have a different vibe. Polyprops tend to sound very big with a flat frequency response. Polyester (Mallory 150's) sound more hi fi (upper mid clarity) like a brown or early aa series Fender. Polyester is also especially well behaved in high gain circuits. But they tend to lose top end when the amp is really cooking IME.

Mouser is my personal favorite for componant orders.

Chuck

[Robert M. Martinelli]

Interesting! Should I get the parts from any electronics supplier? And will a 40W soldering pencil iron be sufficient?

thanks,

brian

Yes, as Chuck says, it will be enough for most application, I' ll only add a small trick to make your soldering iron a little more flexible. The 1N4007 is an 1A 1000 V diode, so it will be OK for a 40, 50 or even a 100 W heater.

The idea is that the diode will cut half of the mains' incoming sine wave, cutting half of the power; when you need full power you just have to press the push-button and the diode will be bypassed, releasing full power. Releasing the push-button switches back the soldering iron to half power.

This way you can have a 20/40W, 25/50W or 50/100W soldering iron at your touch.

Simple and ( cost ) effective.

Hope this helps

Best regards

Bob

P.S. my apologies for the poor drawing....

[bhuether]

Yeah I am hoping that the amp's top end will be retained so I guess I will choose polypropylene.

I was curious if you have any thoughts on the amp's bass response. I have a separate post here:

http://music-electronics-forum.com/s...90596#poststop

Of course you have already done enough!

thanks,

brian

[Chuck H]

Thats a nifty trick. 20 watts might be too cool though. It depends on the design of course. But it would be good to know what the temp was at 20 watts as well as 40. Not sure how you could do that without spending more on a piece on test eqipement than you would on an adjustable iron though.

I remember, when I was a boy my dad had an old Weller soldering "gun" the thing was enormous and hummed loudly when the trigger was depressed and all the lights in the house would dim. The thing had a headlight on it... Very cool. It probably could have used a half power mode switch.

Chuck

[Robert M. Martinelli]

Thats a nifty trick. 20 watts might be too cool though.

I remember, when I was a boy my dad had an old Weller soldering "gun" the thing was enormous and hummed loudly when the trigger was depressed and all the lights in the house would dim. The thing had a headlight on it... Very cool. It probably could have used a half power mode switch.
Chuck

I used this trick on a 50 W soldering iron, and 25 W is perfect for small works ( PCBs, guitars and the like ), while 50 is good on pots, tube amps etc.

I used to have a big soldering "gun" as well in my early "electronic" days, but it was "only" 100W. It didn't even come close to dimming the lights ( but I managed to open the house's mains safety breaker a few times with my first experiments ).

Cheers

Bob

[Robmosis]

Have you simply tried different tubes? It may just be the easiest way. Maybe a different preamp tube Like a 12ay7 or something. Worth a try if you haven't tried. I know it may not seem to be the answer but in my short experience with my amps I have noticed that the tubes have an effect on a lot more than just tone.
Also have you just tried different speakers? I am in the process of learning all about what makes a tube amp tick and have found myself over thinking things quite a bit. I think its natural to want to use the knowledge we have attained which can be a curse at times.
Hope my simple opinion was of some thought.
Rob

[bhuether]

Well, incidentally I ordered a new guitar so I figure I may as well wait til it arrives (a Suhr Modern!) and assess from there. And I am going to get a new speaker cab as well. So I will wait until I attempt mods but will definitely bookimark this thread and return!

thanks,

brian

[petemoore]

tubes

I read about and recently have been trying out with PI's and starved plates and 1rst preamp tubes.
From what you described, if you have 12ax7's in the preamp, lower gain / higher current plates, such as 12a_7 tube swaps may help or cure hardness of attack.