Tube Amps / Music Electronics
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|7/26/2000 6:20 PM|
|Jim S.||Morley JD-10 preamp/pedal|
Does anyone have any info about what type of circuit is inside a Morley JD-10? I own one of these and think it has one of the best emulations of medium-gain tube overdrive.
For those of you not familiar with this pedal: the JD-10 has a gain control, an output volume, and a 3-band EQ. The knobs are in front of the pedal, not on top where the footswitch is. There are also two pushbuttons on the front: a gain boost and a speaker cab emulator.
I find the gain boost mode to be a bit too over-the-top. The sound gets mushy and overcompressed. However, the tones you can get with the boost turned off are quite impressive for a SS unit. You can go from clean to edgy to a very nice sustaining crunch, depending upon the setting of the gain knob. The JD-10 was really meant to act either as a direct recording device (where you would push in the spkr emulator button) or as a simple preamp that you would plug into an amp's effects return jack. Supposedly, Jerry Donahue (the "JD" in JD-10) used this unit to bypass the tube preamp in his Matchless amp, although I don't understand why he would prefer this arrangement to an all-tube signal path.
The JD-10 has some flaws which prevent it from working that great as a regular stomp box. For one, the controls are hard to read or get at when it's sitting on the floor. Secondly, the EQ appears to be implemented as a typical tone control stack, where the midrange frequencies tend to be dipped unless the MID control is turned pretty near all the way up. For playing in front of a typical amp, I find these settings are necessary: Treble: no more than 9:00; Mid: at least 3:00; Bass: no more than 8:00 or 9:00. This doesn't leave much room for further tweaking.
Despite all of this, the JD-10 is a cool box. The overdrive has very nice, even harmonic content and lacks much of the harshness or coldness of most SS overdrive/distortion pedals. Also, the attack and decay of the notes feels right.
I would be interested in others' opinions of this pedal and any information about what makes it tick.