finishing touch...any ideas?

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iknowjohnny
Posts: 1070
Joined: Thu Apr 24, 2008 2:10 am
Location: los angeles

finishing touch...any ideas?

Post by iknowjohnny »

heres the deal. been working on this marshall style 50 watt high gain amp for months. it's gone thru numerous changes and has sounded anywhere from fantastic to ehhh. The other day i found the magic nail and the amp is literally amazing in higher gain settings. And i'm not using that word lightly. I have never played a high gain sound this good. However, while the frequency balance is now quite good, the highs when turning the gain down to medium and turning the guitar volume to 4 and using a vintage style single coil, theres just a bit too much top. I have tried several caps across the gain pot with a trim pot in series to try and get it perfect when the gain is set lower, and so far it's helped, but i want near perfection. The higher gain tones are just insanely good to my ear, so i don't want to ruin that. A bit less highs elsewhere won't, but i fear it will if i trim in the pre. I just want to roll the top off EVENLY from maybe 1k on up but w/o dulling it. i have tried caps to ground at various points, caps across the PI plates and across each plate R, the preamp plates, etc etc. all the normal stuff. Anyone have any less common ways that might be just the ticket? Particularly for the PI on back i think. The pre is great as is and i'd hate to try and take highs out there for fear of killing this tone.

If i haven't made this clear, again i'll say that it's the cleaner tones i get by turning the gain to say 1:00 and rolling my guitar down to 5. thats where i want to smooth out the top. Any less common ideas out there? (no cut controls or conjunctive filters....don't like either)
skeezbo
Posts: 115
Joined: Sun Dec 24, 2006 12:07 am

Re: finishing touch...any ideas?

Post by skeezbo »

It seems strange that the tone would be so different. You've maybe already thought of this, but I was just thinking outside the box: is there a cap bypassing the volume control on your guitar? Too large a value (over .001) with no resistor will cause a similar problem.

Hope this helps,
Skeep
iknowjohnny
Posts: 1070
Joined: Thu Apr 24, 2008 2:10 am
Location: los angeles

Re: finishing touch...any ideas?

Post by iknowjohnny »

yes, but thats not it because i don't use tone controls on my strat so i use one of them in series with the cap as a variable resistor. So i can have a .001 across my volume and dial it down to any degree of highs i want to pass when i turn it down. But the thing is, when the amp's high end is right, it doesn't matter where my guitar's cap is set and it just sounds perfectly balanced.
Jana
Posts: 1314
Joined: Sun Sep 07, 2008 10:40 pm
Location: Minnesota

Re: finishing touch...any ideas?

Post by Jana »

you could try larger values on the phase inverter cap, the one that is usually 47pf or 100pf across the two plates of the PI. try a 250 or a 500p to trim a bit of the highs off.

also, if you ditch that bright cap on the strat volume and learn to use the tone control you might just be there. I play a strat 99% of the time. Tone controls on a strat are your best friend. Seriously, ditch that bright cap on the strat volume and wire up a tone control instead, on all the pickups. I find that one tone for either the neck and middle and the other for the bridge works just fine.

You have found that you need a lot of highs to get a good distortion sound but at less gain settings it gets really shrill. well, without the bright cap on the strat when you roll down the volume for a cleaner sound, let it work for you and get a little *duller* which is just what you want for the cleaner sounds.

BTW, it is never done, there will always be something to "improve" on it, LOL.
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Tonegeek
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Re: finishing touch...any ideas?

Post by Tonegeek »

iknowjohnny wrote:heres the deal. been working on this marshall style 50 watt high gain amp for months. it's gone thru numerous changes and has sounded anywhere from fantastic to ehhh. The other day i found the magic nail and the amp is literally amazing in higher gain settings. And i'm not using that word lightly. I have never played a high gain sound this good. However, while the frequency balance is now quite good, the highs when turning the gain down to medium and turning the guitar volume to 4 and using a vintage style single coil, theres just a bit too much top. I have tried several caps across the gain pot with a trim pot in series to try and get it perfect when the gain is set lower, and so far it's helped, but i want near perfection. The higher gain tones are just insanely good to my ear, so i don't want to ruin that. A bit less highs elsewhere won't, but i fear it will if i trim in the pre. I just want to roll the top off EVENLY from maybe 1k on up but w/o dulling it. i have tried caps to ground at various points, caps across the PI plates and across each plate R, the preamp plates, etc etc. all the normal stuff. Anyone have any less common ways that might be just the ticket? Particularly for the PI on back i think. The pre is great as is and i'd hate to try and take highs out there for fear of killing this tone.

If i haven't made this clear, again i'll say that it's the cleaner tones i get by turning the gain to say 1:00 and rolling my guitar down to 5. thats where i want to smooth out the top. Any less common ideas out there? (no cut controls or conjunctive filters....don't like either)
If I understand the post, you are lowering the gain on your amp and lowering your guitar volume and then it has too much high end? If the highs only increase (or lows and mids go down with highs staying the same) when you change the guitar volume then, yes the treble bleeder on the guitar might need adjustment. If you are lowering the gain on the amp and it happens then look to the amp for the fix. It might be a combination of both circuits. Has the amp gain control got its own treble bleeder (AKA bright cap)? Normally that would be on a switch but they might be across any pot that controls volume.

My experience is the opposite of yours, most amps I have used got more highs when they were pushed and got duller when turned down. Personally I like having a treble bleeder on the guitar as it helps with my situation. I use my guitar tone controls sometimes, but I don't want to mess with them every time I change volume. The treble bleed keeps the mud out which helps the guitar sound more consistent across a wider range of guitar volume settings IMO. It does take a bit of experimentation to get the right cap/resistor values for the bleeder and will vary depending on the guitar and amp used.
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