Fender Amps--Unwanted Distortion / Matchbox

John Russell · From: Austin, Texas

I know some of you guys prefer the sound of old Fender Twin or Vibrasonic amps. How
do you deal with the distortion?

I just got a new Fender Stage 160 amp (solid state) which pretty much replicates the sound
of the old tube-type amps and that includes the "soft clip." It’s OK for guitar but I'm used
to super clean tone for steel. Could it be the speakers? The Stage 160 has 2x12"
Celestions.

At the Jamboree in Dallas I was talking to Gene Fields and he mentioned that steel guitar
amps are designed so that the pre-amp can handle the hotter output of PSG pickups and
that's why the Fenders clip.

I'm wondering if there's a quick fix for this. How about the Matchbox? Someone
mentioned on the Forum that it's designed to match impedance to the amp and would fix
the clipping.

BTW, I'm using stomp boxes for reverb, delay and EQ. These patch into the FX loop. I
tried turning down the channel volume on the amp and boosting the gain on the EQ box. It
didn't help. (These effects don't cause problems with my Peaveys.)

Any suggestions?

John Russell

Keith Hilton · From: 248 Laurel Road Ozark, Missouri 65721

John, here is my opinion. I question if steel guitar pickups are all that HOT. If they were, you would hear all the pedals, knee levers and changer parts moving.
Next: Your problem does not sound to me like a impedance problem. If it is, a match box will send a stronger signal. Sounds to me like you are over driving the signal that the Fender amp input will accept.
You have 3 stomp boxes in line. Did you know that "all" powered stomp boxes create gain? Each one multiplies what comes in. That can become a real problem, because many stomp boxes don't have volume controls for the signal.
I suggest starting out with just your guitar, pedal and amp. If that works, add one thing at a time.

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Mike Bagwell · From: Greenville, SC, USA

John,

Try a 12AT7 or a 12AU7 tube in place of the 12AX7 in the first stage of the pre-amp.
Looking at the back of the amp the first stage pre-amp tube for the reverb channel is the 2nd tube counting from the right to left.
The 12AX7 has an amplification factor of 100,as opposed to the 12AT7 which is 70, and the 12AU7 is 40.
Another place to reduce gain with tube subsitutions is in the driver curcuit, this tube is located right beside the power tubes (its the small tube nearest the power tubes).Try a 12AU7 in this location.
This easy mods will not harm your amp in anyway and should reduce the gain to a more acceptable level.

Mike

Michael Brebes · From: Northridge CA

If this amp has the same thinking as the old amps, then it has two inputs per channel. If this is the case, use the lower gain input which should fix your problem. If it doesn't then you might have to pad the input. Two 68K ohm resistors in series, with the steel on the top leg, the other end on ground, and the middle attached to the amp, will simulate the lower gain input of a standard old style Fender tube amp. If you don't get distortion when your volume pedal is approximately half open then this might do the trick.

Robert Parent · From: Gillette, WY

Do you still have a distortion problem with only the amp, volume pedal, and steel. I have had stomp boxes in the past which could not handle the higher signal levels generated with the psg. You may have a similar problem with the stomp boxes in the effects loop. Just a thought.

Dan Tyack · From: Olympia, WA USA

I think Celestions are great for steel. To hear distortion from the speaker you would have to be playing mighty loud!

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www.tyacktunes.com

Bob Hoffnar · From: Austin, Tx

I deal with this problem all the time. A matchbox along with plugging into imput #2 on Fenders will fix you right up. I use a Super Sustain Matchbox by Goodrich.

Bob

Rick Barber · From: Morgan Hill, Calif. USA

Without changing any designs it seems like you can only adjust input levels . Your amp and each box in front each will have a specific input level when reached will start to distort. In addition each box has its own gain or loss which controls how hard the the next box is hit.

1. go from guitar to amp. Adjust drive level to amp until its clean. Or pad your guitar signal at the amp input.

2. now infront of amp add an effect adjust its gain until it driving amp is clean.

3. add next box in front of first one , adjust its gain level for overall clean.

4. now add volume pedal . At max volume its clean.

5. if you get stuck , rearrange the order of boxes and start over. This is because some of your boxes will distort less than others at a given input level.

6. if the amp is the problem then either it was meant to distort by design to emulate a tube amp OR you need to pad your input down (try 10 dB)...

was wondering if the amp is supposed to even "soft clip" at low levels ?? To me clipping is clipping ----what is soft supposed to mean?? A little clipping , clipping at all levels, filtered clipping --- I havent the slightest.

Rick Barber

Bob Hoffnar · From: Austin, Tx

Man, You guys sure know how to make a simple problem complicated !

Bob

John Russell · From: Austin, Texas

Whoa!

I didn't anticipate all the responses to this post. I'll get back to you regarding the second input technique. Sounds sensible.

As far as the effects adding too much singal, I wonder if that's it cause they come in after the pre-amp (in the loop). But I'll try eliminating each one at a time and see what happens.

I may have to try the Matchbox. If this works, I'll have one sweet sounding rig, the new Fender sounds pretty nice and NO TUBES. (It's light, too.)

Thanx for your ideas, everybody!

John

John Russell · From: Austin, Texas

I tried plugging into the #2 input and it lowered the volume considerably, maybe by half. I couldn't really crank it as it's getting late around here but I don't think the that solves the problem.

Rick B. the soft clip is best described as a little warm fuzz in the bass notes, audible distortion, but not the harsh kind you associate with solid state amps. I hear it when playing chords on the lower 4 strings of my S12U guitar, even up toward the 12th fret. The higher notes don't do that on the clean channel. There's a "drive" channel with a settings to increase or decrease the dist. This channel gives that same distortion across the spectrum--its for lead (rock) guitar.

The owner's manual says the input impedance for #1 is 850K ohms and #2 is 66K ohms. That seems like a huge difference but it seems to cut the volume by about half.

I'll have to try the Goodrich or some such device or maybe figure out how to "pad" the input by a lesser amount.

I did not try playing without the effects, I hope to retain the effects for several reasons, but I'll see what difference it makes without them.

JR

Sam Marshall · From: Chandler, AZ USA

Yeah, the #2 input does lower the input signal by 6dB (or by one-half). It may still overdrive the input as you turn it up. Even the clean channel gets a little crunchy when you turn it up with a guitar plugged into #1.

I have a Princeton 65 (from the same series as the Stage 160). Though I got it as a lightweight guitar amp, I found that it makes a good low volume practice amp for steel, too. I'll have to try a Stage with my steel.

Sam in AZ

[This message was edited by Sam Marshall on 23 March 2000 at 09:00 PM.]

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