Tube Amps / Music Electronics
For current discussions, please visit Music Electronics Forum. New: view Recent Searches.
New: visit Schematic Hell!
The sunn still shines online!

Listen to great tunes streaming live right now!

ampage archive

Vintage threads from the first ten years

Search for:  Mode:  

Re: This Box Goes To Negative 11!

4/8/2003 2:27 AM
Soren Re: This Box Goes To Negative 11!
After snipping the diodes, try feeding this (it is hungry) unit from 9VDC up to 18VDC. Then the negative will turn into capital letters so you get NEGATIVE 11. More headroom gives the signal room to breath and sound the way it should.  
By the way the YJM 308 has a 100 ohm resistor in series with the power supply. For our purposes here, replace it with a jumper for the most headroom. There is no need to bring down the voltage when we are experimenting to bring it up. A temporary jumper can be made by wrapping a few stranded copper wires around the two ends of the resistor. Or use little clips.  
An analogy to voltage headroom is like this, pluck your low E string, see it vibrate, touch the side of it gently, see it vibrate less. That is like less headroom. It sounds squashed and dull.  
4/6/2003 12:08 AM
Soren Arons Site ?
Aron's link does not work:  
Is there a different URL for Aron's site ?  
4/6/2003 10:23 PM
Chris ( CMW amps )

Soren ,  
here you are :  
Aron's site did move some time ago but the links on Ampage aren't updated ( not to offend tboy ! ) .  
4/8/2003 2:51 PM
taxi driver Re: DOD250 Vs. YJM308
that's funny, Yngwie him self says his in an exact replica of the old the current issue of guitar world.
4/8/2003 4:56 PM
Mark Hammer
Well it IS an exact replica, but there were small differences in component values over different issues of the same basic pedal that seemed to work for his particular setup so DOD marketed a signature model version with those value changes. In practice it isn't much different that some of the variations in the many signature models of Strats. The Buddy Guy, Richie Sambora, and Jeff Beck Strats probably CAN sound and feel a little different from each other because of the electronics, neck dimensions, etc., but like the genetic differences between human beings, there is probably much more overlap than actual difference - they will all be easily recognizable as Strats rather than something else in blindfold tests. These two versions of the same DOD pedal will sound very similar in most instances. If DOD was in the habit of releasing pedals with mod instructions in the user manual, it would be as easy as opening up the manual to page 3 and reading about which cap values to change, but since they won't likely be doing that you get to see two releases of essentially the same pedal.
4/8/2003 5:35 PM
The old Gray model used a different chip, an older one, like maybe one of those 741's. The new YJM 308's have modern production 4558's. Also, the diodes where a different type, germanium I think, and hard to find I guess. According to what I read, they are working on a model which is the same as the gray model. A replica of something does not make it the same as the original. Yngwie may indeed have authentic gray models in his arsenal.  
In any case, my advise to guitarists is try to tweak the circuit for what you like to hear, experiment with different diodes, and forget about model versions. If you really care about tone, your sound, you would do well to build a point to point box with good quality capacitors. The difference in sound will be much greater than differences in Op amp type or clipping diodes used.  
I think any type of clipping diodes in a circuit have to be carefully tuned. To my ears, they cause a chirping sound on the attack of the note, and that to me sounds unprofessional, although the effect of the distortion may sound pretty cool. There is a balance between a cool sounding distortion effect, and something built with tonal quality.  
4/9/2003 10:19 PM
Something I just noticed. I had a set of unused white aged Fender guitar knobs and found they fit perfect and look very cool on the YJM. It's got numbers too, to write down control settings in a complex setup. I can engrave an 11 between the 1 and 10 on them! For the YJM, the black Fender guitar knob would look great if the numbers where painted gold. This will be my trademark look for these pedals!  
<<First Page<Prev Page 2 of 3 Next> Last Page>>