Amp for fiddle

[Smokebreak]

"I been drinkin gin all night
Cause my ol gal ain't treatin it right
I don't give a damn if I eat or not
Just gimme another shot"

I see what I think is referred to as treble peaking in Marshall types inbetween 1st and 2nd stages.
http://www.drtube.com/schematics/marshall/1986u.gif
Adds a lot of gain, 500p is bright, clipping it is kinda similar to clipping trad bright cap. Emplexeador uses 1n which is more pleasing I've experienced.

Yea the Rocket has the same "cut" I believe and I keep meaning to rewire it everytime i'm in there

[Leo_Gnardo]

I see what I think is referred to as treble peaking in Marshall types inbetween 1st and 2nd stages. Adds a lot of gain, 500p is bright, clipping it is kinda similar to clipping trad bright cap.

Yea the Rocket has the same "cut" I believe and I keep meaning to rewire it everytime i'm in there

"Wine wine wine, do yer stuff." CC&theLPA again.

OK, gotcha, that annoying nails on a chalkboard Marshall triple bright cap circus. Yes clipping that thing out works wonders. It's really just what you say, much like the bright cap on ye olde Fenders. Except brighter and on a fixed resistor. So - we know enough to avoid that, and I doubt you'll be cascading gain stages for your fiddle amp to get crunch gain like MV Marshalls.

If there's to be a bright switch you'll be carefully selecting a cap, likely less than Fender's 120 pF, when you start building. 0.12 nanofarad for Martin. At least we got away from milli milli farads. Reminds me of a bug with a thousand legs. Thoroughly modern... vanilli.

"Drinkin' wine, spo-dee-o-dee" Jerry Lee Lewis.

[Tillydog]

This is great!...and cocktail hour is officially here. Can't believe I forgot to grab a bottle of gin yesterday
So how does this work for say, a treble peak network, typical 470p/470K(which generally does not please my ears btw)?

If you can bring yourself to do it, I think you'd find circuit sim software really useful. If you can get to grips with LTspice, or similar with Steve Bench's tube models, you can build all sorts of amps, change capacitor values, add filters, etc. and see the effect on the frequency response all without heating the soldering iron. Obviously it's no use in isolation - you need to build something to actually hear what it sounds like, but it is a hell of a tool for correlating circuit changes with differences in what you hear. (I've found Steve Bench's models to be scarily accurate in a number of different circuits.)

Sim software is a bit like a sat-nav: Old-timers will tell you that you don't need one - just learn to read a map; Conversely, believing what it tells you absolutely will get you into all sorts of trouble; but if you can listen to what it's telling you and apply that information to what you see and hear in real life then it can save you going down an awful lot of dead ends!

[Smokebreak]

I messed around with LTspice 6mo ago and the concept and software was over me head. I'll give it another go.
I'm going to order some 50w transformers for a western electric circuit. Triode has a triple sec PT that should suit. The double Princeton sounds good but I've had a damned time reproducing reverb channel sounds (verb on zero) without that recovery stage. I think it adds some meat even with no verb running. To flog a horse, the v channel of any fender is much richer to my ear than the normal channel, with verb/vibe on zero. I'm sill a bit baffled by this, as if I could get the sweetspot of a Princeton in a 50w w/o verb ,that sounds like a winner , but wouldn't that be a tweaked bassman? That seems like a good start. Speak now or hold peace and lets build this damn amp!

[Leo_Gnardo]

The double Princeton sounds good but I've had a damned time reproducing reverb channel sounds (verb on zero) without that recovery stage. I think it adds some meat even with no verb running. To flog a horse, the v channel of any fender is much richer to my ear than the normal channel, with verb/vibe on zero. I'm sill a bit baffled by this, as if I could get the sweetspot of a Princeton in a 50w w/o verb ,that sounds like a winner , but wouldn't that be a tweaked bassman? That seems like a good start. Speak now or hold peace and lets build this damn amp!

The difference is that loss'n'gain circus in the reverb amps, where you send the clean thru 3M3 parallel with 10 pF, mix with rev. coming in on 470K, and in some cases refer the mix point to ground w/ 220K (you can change this, or have none, for more or less mixer loss,) then run the result thru another input-style triode. Most folks that have cared to talk about it to me, reckon this extra stage makes the sound a bit less clear, compared to the same amp without reverb. (64-65 Deluxe vs Deluxe Reverb, Princeton vs. Princeton Reverb, for instance). BUT if you like it, no problem! It does give you the opportunity for a extra tone-shaping. (Call it a tweaked Bassman if you like, using that extra gain stage for tone shaping.) I'd say put in a reverb while you're at it, sounds good with fiddle, but not smashy sounding hence I suggested a dwell control. And/or a resistor in series with the reverb drive transformer primary 10K - 20K 2W, I've done & it smooths things out a bit for cheap. Dick Dale reverb you don't need with fiddle. If you're worried about reverb spring crash noises, leave out the traditional 12AT7/transformer & spring box, but do put in a triode buffered send so you don't "load down" the original signal, & return (probably won't need a buffer just go to the 470K) jacks & use a small digital reverb (MicroVerb, LXP-1) - works great! You can use any delay FX here, DDL, chorus, flange, looper, think Jean Luc Ponty. Let the guy go wild at solo time. Or not.

Triode, you mentioned, I know - the parts supplier, but it pushed the button in my brain that says, yes put in a triode switch for your output tubes. For that smooth old fashioned tone. Cuts power by 1/2 or 2/3 but another tone choice that may work out a winner with fiddle.

OK I'm out of ideas, pick the ones you like & run for the goal post. That box of Triode iron arrives next week. Keep us posted - this is gonna be good I'm sure!

[Structo]

Always loved Jean-Luc Ponty playing.

Especially Return To Forever

http://www.youtube.com/watch?v=0FaS7NbldY8

I played violin from the 4th grade through grade 12.

Never electrified it nor could I improvise at all.
I was a music sight reader.

Just played the dots on the page.

[martin manning]

The difference is that loss'n'gain circus in the reverb amps, where you send the clean thru 3M3 parallel with 10 pF

There's another one of those so-called "treble peakers." These things are a high-pass shelf filter, so there are two break points. The lower frequency +3 dB break is easy because it is always determined by the parallel RC (the upper one depends upon the surrounding circuitry).

For the Marshall values 470k and 0.47 nF it's 159155/470/0.47 = 720 Hz

For the Fender dry bypass it's 159155/3300/0.01 = 4822 Hz

BTW, it wasn't mili-mili, it was micro-micro- as in uuF, or MMFD on old schematics.

[Reeltarded]

Easier to write than talk about. Most everything is in uF so that is what I pause before saying each time I come to a value in a conversation. Been testing out nF because it's actually easier to make the funny number.

220n is easier than, fer instance...

[Leo_Gnardo]

The difference is that loss'n'gain circus in the reverb amps, where you send the clean thru 3M3 parallel with 10 pF

There's another one of those so-called "treble peakers." These things are a high-pass shelf filter, so there are two break points. The lower frequency +3 dB break is easy because it is always determined by the parallel RC (the upper one depends upon the surrounding circuitry).

For the Marshall values 470k and 0.47 nF it's 159155/470/0.47 = 720 Hz

For the Fender dry bypass it's 159155/3300/0.01 = 4822 Hz

BTW, it wasn't mili-mili, it was micro-micro- as in uuF, or MMFD on old schematics.

'Zackly as you say Martin!

To tame the sizzle in Fenders, sometimes I've clipped out the 10 pF or swapped in an even smaller pF - 8 and it adds a little "air" and reduces ear-bite.

milli micro = nano, hey it's the mathematics of small numbers. What a former employer had to say to me, atto-boy! It always made me feel - - - very very small.

[martin manning]

Besides, if you're hip, nano is the new pico.

Try the veal...

[Smokebreak]

SS or GZ34?

[Smokebreak]

Check out low and hi pass there. It will be your friend.

http://www.ekswai.com/en_filters.htm

Ok I need to write this out to make sure I've got it correct

High pass filters set a point where frequencies below a certain point can't pass. Examples would be coupling caps where the higher the value sets the cutoff at lower frequencies. Ck would be another example.

Low pass filters set a point where frequencies above a certain point can't pass. The only example I can think off is a small cap acroos a plate resistor where the higher the value, the lower the cutoff? Higher values here mean less treble?

What about treble peaking network? Is this a high pass ?
Edit: sorry Martin I missed your post about the TP being high pass.

[Leo_Gnardo]

Ok I need to write this out to make sure I've got it correct

High pass filters set a point where frequencies below a certain point can't pass. Examples would be coupling caps where the higher the value sets the cutoff at lower frequencies. Ck would be another example.

Low pass filters set a point where frequencies above a certain point can't pass. The only example I can think off is a small cap acroos a plate resistor where the higher the value, the lower the cutoff? Higher values here mean less treble?

What about treble peaking network? Is this a high pass ?
Edit: sorry Martin I missed your post about the TP being high pass.

All correct. The RC filter slopes aren't super steep, so out-of-band signals are attenuated but not totally stomped, unless it's way out of band. As you apply these filters stage after stage you sculpt the frequency response.

For instance I had a customer who wanted his silver bassman modded to resemble the "stuck wah pedal" of Scorpions' Rudolph Schenker. I cascaded 3 narrow band stages & he was a happy camper. You'll be going a bit more wide band in your amp I'm sure.

[martin manning]

Martin I missed your post about the TP being high pass.

The treble peaking nw and the Rk-Ck are both HP Shelving filters. Merlin Blencowe's preamp book has a pretty concise chapter on this stuff, and I'd recommend getting a copy. Tons of good info and a bargain at twice the price.

[Smokebreak]

Thanks a bunch guys. Getting my ducks in a row...
Let's start with :
5f6A, 15" combo
-Cut. 250k/.022 with smallish series resistance
-Resonance. Focusing on mids? Or lows?
-Triode switch(still pondering as I've never experienced this)
-Presence? Miles, how would I handle NFB without presence? Just tack it on fixed? I don't understand why we'd lose presence in favor of a cut, but that's only because I'm still coming to understanding of frequency shaping;)
-what about presonance?
-no verb as he is adverse
-baggs in front. He asked me last night if we could do a channel with a baggs built in, and that is still blowing my mind up

We've learned that when he soundchecks, he has to go really bright, but then it's sits right in the mix with the whole band, which is why I bring up the question of presence.

Anyone on this board offer custom punched chassis?I'm gonna need all the time I have here