Bright Switch too Bright on Top Hat!!!

Discussion in 'Amps/Cabs Tech Corner: Amplifier, Cab & Speakers' started by rawkguitarist, Dec 16, 2004.


  1. rawkguitarist

    rawkguitarist Member

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    I have a little Top Hat Prince Royale 1x10. It’s a 4 watt single ended EL84 powered amp. The Bright switch when set “Bright” is too harsh, but without it my humbuckers are a little dark. Now I’m quite a novice, but I can see the Bright switch when set to bright seems to remove a small yellow capacitor from the Volume pot. It reads 150m .0022UF 15%, 630v 9330. Don’t worry, I’m not going to poke around in there as inexperienced as I am. Would my amp guy be able to change that to a capacitor that is less of a drastic filter? I guess he could even put a tone control (on the bottom of the amp unseen).

    What do you think? I believe this amp is based on an old supro????
     
  2. Jon Silberman

    Jon Silberman 10Q Jerry & Dickey Gold Supporting Member

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    22 pf is already a very low value for a bright cap, Fenders use what, 64 pf? My Traynor YGM-3 uses 250 pf, my Traynor YBA-1 has been rewired to 100 pf (down from 1000, believe it or not), my Reverend Hellhound uses 50 pf, and I've rewired my Tone King to use 33 pf.

    What I'm trying to say is, in this case, I'd advise relying on the tone controls on your guitar or amp rather than further lower the cap value.
     
  3. Kevin

    Kevin Member

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    That's actually a 2.2nf. I think Brian uses a 180pf in the Club Royale. I would think you could try something in that range if you're comfortable messing with it. My CR came without a bright switch so I used a pair of short clip leads and swapped a few caps in and out until I found the value that sounded best with by humbuckers.
    You might also want to try a darker sounding speaker. Maybe shoot Weber an email and see what he suggests.
     
  4. Jon Silberman

    Jon Silberman 10Q Jerry & Dickey Gold Supporting Member

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    nf? What's that?

    A 180 pf bright cab, on the other hand, is VERY bright and if that's what you've got, definitely try something around 50-64.
     
  5. hear and play

    hear and play Member

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    Ask the builder: Brian (Gerhard). He's treated me just great over the phone.

    I don't have an e-mail address (couldn't find one on the site: tophatamps.com). Here's a phone number:

    TopHat Amplification 714.447.6700 ..... 9-5 P.S.T.
     
  6. Kevin

    Kevin Member

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    nanofarad :D

    Between micro and pico. Not a common term to use in the amp world. 2200pf. That seems perty darn bright to me.
     
  7. rawkguitarist

    rawkguitarist Member

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    Here’s a little more info on the amp. Since it is a small amp, like a champ it is very simple. It has 1 volume control, the Bright switch and a Boost. Which, it looks like it’s simply a boost pedal circuit wired in to the amp (may be the boost in his wonderboy pedal).

    It also occurred to me that I could put a tone control in the spot where the bright switch is. If I wanted to sell the amp, I could put it back and you really couldn’t even tell it. I doubt I’ll sell this amp, love it too much (never say never though). Again, I’m a novice just inquiring, would it be simple to just place a tone control that controlled the amount a capacitance to the circuit? The amp circuit itself is really simple, and open.
     
  8. fullerplast

    fullerplast Senior Member

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    Kevin's right. It is a very large bright cap. If you can solder, I'd suggest just trying a few from 470pf down to 47pf and see what you like. They are cheap.
     
  9. Jon Silberman

    Jon Silberman 10Q Jerry & Dickey Gold Supporting Member

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    2200 pf is like staring into the sun. No wonder the amp's too bright with the switch on!
     
  10. rawkguitarist

    rawkguitarist Member

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    Like I said, I'm new to this stuff. So the capacitor actually increases brightness. My inexperience caused me to think it was a component that attenuated the high frequencies, and the bright switch was removing it. But you're telling me it actually does increase highs. OK…

    I’ve got Brian’s Phone # on my cell phone, I’ll call him at lunch.
     
  11. TheAmpNerd

    TheAmpNerd Member

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    Well no not really. You have all your tone going into the amp. The volume pot attenuates the signal. With out bright caps, what happens is when you turn down the volume from 10, the highs get attenuated the most. Volume pots have small bright caps across them to keep the highs when you turn down.

    On some amps with bright switches...there is yet another cap that is wired to the volume pot so the high frequences bypass it. Most of these devices are passive, they don't add anything, the keep it from being removed.
    When you play at 10 nothing is being removed from the incoming signal, (at the volume pot). So the bright cap
    doesn't matter. It is when you turn down, you notice
    the abundance of highs that are not being attenuated
    along with the mids and lows.

    Like most deep switches...The standard circuit has some of the bass removed...when you flip the deep switch, A
    larger cap lets more of the bass frequencies flow through the circuit (less bass is removed).

    Kinda like HVAC systems, they work only one way.
    That is air conditioning does not pump
    cool air into your house, it pulls the heat out!

    Hope that helps : )
     
  12. rawkguitarist

    rawkguitarist Member

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    Thanks guy's! Helps a lot! I did put a 500 pico in there, replaced the 2200. Did impove it, but still a little to harsh, going to experiment a little more. I love learning about this stuff...
     
  13. Jon Silberman

    Jon Silberman 10Q Jerry & Dickey Gold Supporting Member

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    It's amazing the difference a teeny little cap can make, isn't it? :D
     
  14. rawkguitarist

    rawkguitarist Member

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    I had a tone control put in series in the circuit, using the 500 pico cap. I know it looses a little gain in the circuit, but it sounds pretty good. I'm still not sure, cause I had fatigued ears by the end of last night, but this morning it sounded great to me.

    With the amps pentode EF86 I had to simple put in series. The original AC-4 worked this way (correct??) and several other small amps of that era.

    What do you guy's think?
     
  15. lookslikemeband

    lookslikemeband Member

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    I've had Brian go over BOTH of my TH's to "tighten" them up and check everything.

    He's THE MAN!!!

    Here's his e-mail addy: tophatamps@aol.com

    Or, like some said, call him. He's always been cool to everyone on the TopHat board.

    BTW. On my King Royale, the bright switch is really subtle (it's an early version - script logo).

    To be honest, the Channel 1 - with just volume and tone, does me just fine!! I run my Les Paul into it, and tone it out... Makes me sound like a no talent early Edge (as the KR is basically a Vox AC-30 top boost 33 watt Class A amp)

    Lance
     

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