Orange Squeezer Diode

[Mark Hammer]

Thanks for posting this followup.  I am confident that it is encouraging to others to know that there is usually another way around the particulars of many designs, and that you can get them to sound the same even when it doesn't seem to use the same ingredients.

Sometimes, you follow the recipe and it says "use 1/2tsp of salt, 1tsp sugar, 1tsp vinegar, and 2tbsp tomato paste", and other times, you just reach for the ketchup and get on with it because when all is said and done, it will taste exactly the same.

[krister]

Thanks, Mark, what do you think of the external bias pot concept?

[Mark Hammer]

The trimpot adjustment should ideally be something you do once, properly, and then never touch it again.  I can see where someone might want a small chassis hole to be able to adjust it while plugged in, but any convenience of having it panel mount is offset by the inconvenience of it being moved from the sweet spot.  There ARE instances where trimpots can and should be chassis-mounted, even if the full range is not usable (e.g., bias controls on phasers, the trimpots on Dr. Q/Quack).  But this is one of those instances where if it's set right, you won't want it to move.

Here's what I think a sensible and flexible Orange Squeezer could have ("should" have is your responsibility).

1) variable gain for the gain stage to adjust match to input signal level (op-amp gain is really the sensitivity/compression-amount control)
2) output level
3) variable or selectable release time for slower squish like a Dynacomp or the traditional fast in and out of the OS, as well as things in between
4) some tonal adjustment on the audio output to offset the usual treble loss in compressors

More than that probably won't increase functionality of the unit.  Keep in mind that the original had a volume control trimpot on the inside of the chassis, and an on/off toggle, and that was it.  That unit made lots of people happy.

[krister]

Mark,

In your own words, what is your description of the "sweet spot"? What should everyone be listening for? Thank you so much.

[Mark Hammer]

The "sweet spot" is essentially a natural-sounding amount of attenuation and level-recovery.

The FET acts as one leg of a virtual pot formed by the FET and the 82k fixed resistor.  If the FET drain-source resistance drops too suddenly or stays too low for too long, then that pot starts to acts more like a switch than like someone carefully "riding the faders" on your behalf.  Just exactly where that happens for each FET and trimpot is precisely why it IS done with a trimpot and not with fixed resistors.

My gut sense is to adopt the following strategy:

1) First think about what the range of signal levels might be that you will use.  For instance, do you have sharply divergent pickups on your guitar?  Do you plan to switch between guitars?  Do you plan to stick a booster ahead of the compressor at all?  Those sorts of things.

2)  Once you have that assessed and all thought through, figure out what range of possible gain or gain adjustment you might need to produce a reasonable envelope signal.  Here is where it would be VERY HELPFUL FOR FOLKS TO CHIME IN WITH WHAT AC VOLTAGE THEY MEASURE OFF THE STRIPE END OF THAT DIODE ON A STOCK BUILD.

3) When you have identified what the most typical default gain setting might be, arrange to have the gain adjustable so that you can get maybe 25% more and 80% less.  So if the "ideal" default gain is x18, then being able to achieve a gain anywhere between around x2.5 and x23 would be pretty good and let you produce both hard squish and subtle limiting under a wide variety of circumstances.

4) With the gain set to the default value, and the trimpot set for maximum resistance, pick some notes on your D, G and B-strings.  Pick gently, then harder, then harder still.  Do you hear a volume difference?  You probably should, but if you don't, then turn the gain down a bit.  The trimpot is set properly when the harder picking produce an identifiable constancy in signal level.  If it produces an identifiable drop in volume below that achieved when picking soft, then you've get too much compression.  Ideally it should be the case that you get a fairly constant level whether you're picking hard, whacking a chord or playing a loving flourish.  If anything makes it sound like it is ducking its head from flying objects, you've gone too far.

make sense?

[oldrocker]

I have built the OS a while back and have been using it in my signal chain no matter what effect setup I am using. (All DIY's BTW)  But I didn't realize how important having a GE instead of a SI was for this comp until now.  I installed a 1N914 (because it's all I had at the time) and I must've meant to try a GE at a later time.  But I liked the way the OS made my guitar sound so much I actually forgot it was supposed to have a GE diode in it.  My question is what ill effects or non effect should I be experiencing using the wrong diode.  It seems to be working for me and I actually really like the light compression of the OS now.  Do you think I should try the mods for the SI's or just order some GE's and go that way?  I hope the OS still sounds (works) as good as or better then it does now.  Or if it's not broke don't fix it?

[Mark Hammer]

If it works, why change?  EVERY pedal is a compromise design based on expected use conditions.  We should always assume that there will be another means to achieve the same end or create the same effect under different circumstances.  If the circuit underperforms, then there is always the possibility of a particular component being critical to that form of underperformance.  But if it performs well enough for the user, there should be no shame involved in using something other than the textbook parts/methods.

[oldrocker]

Thanks Mark,  Most of the builds I've done are unconventional anyways.  I'm always using substitute parts that I read other builders don't like to use for that particular project.  Yet after trying out the pedal I'll like it and never install the component that the schem calls out for.  I built the Nurse Quacky and finally found a 358 chip that was hard for me to find.  When I replaced it I actually liked the TL072 I had in it better.  It's all a matter of opinion I guess.  Many times I'll mod something or experiment with a build and somtimes it's better or different or worse than what I started out with.  But what I'm starting to realise is if I like what I got the first time around there's no sense in trying to make something that sounds great to me into something someone else thinks sounds great.  Although I love to tinker so I get excited when I read how great a mod turned out for someone and I think I'm missing out if I don't try it myself. LOL!!

[Mark Hammer]

Thanks Mark,  Most of the builds I've done are unconventional anyways.  I'm always using substitute parts that I read other builders don't like to use for that particular project.  Yet after trying out the pedal I'll like it and never install the component that the schem calls out for.  I built the Nurse Quacky and finally found a 358 chip that was hard for me to find.  When I replaced it I actually liked the TL072 I had in it better.  It's all a matter of opinion I guess.  Many times I'll mod something or experiment with a build and somtimes it's better or different or worse than what I started out with.  But what I'm starting to realise is if I like what I got the first time around there's no sense in trying to make something that sounds great to me into something someone else thinks sounds great.  Although I love to tinker so I get excited when I read how great a mod turned out for someone and I think I'm missing out if I don't try it myself. LOL!!

I'd like to say "Been there.  Done that.", but quite frankly, I have to say "Been there.  Bought a condo and moved there."

[krister]

My OS is finished and boxed up and sounds like a million bucks. Thank you Mark for specing out what to listen for, to set the trim pot (see above).

Old Rocker, don't sweat the diode like I did. The Si diode works really well with the output adjustment (higher output) on the op-amp. This effect stays on all the time now and sits on top of my Pro Junior. My PJ has never sounded better. I had figured out with my other amp set-up (Vox Valvetronix) that I really like having the compressor turned on all the time, so I figured I would build the OS, so I could have a unit that I could use with a variety of amps. The Orange Squeezer delivers in a big way...

[oldrocker]

The Si diode works really well with the output adjustment (higher output) on the op-amp.

I didn't do the output adjustment on the op-amp but it still works nice for me.  I keep getting tempted to try the mod just to see what difference it makes.
Yes the OS for me is the answer to my (what compressor to use all the time? question.)  I really like how it smooths out the sound and is so transparent most of the time.

[KMS]

Glad to see you got your project finished up.

I recently made some changes to my multi FX box which my OS is installed in and I do not get any unwanted noise now (I found a loose solder joint and I had some power supply issues that I fixed).

The mods I made to the OS (from reading all of what Mark H and RG have over on GGG) have proved to be very durable mods that give me one of the best compressors that I or anyone else I talk to has ever listend to.

My brother plugged into it and fell in love with it....way better than the compression in his Marshall Stack.

I now have two other compressors to compare it to..(not including the Marshall)...I now have a Digitech RP7 Valve with a excellent compressor and I just bout an RNC (Realy Nice Compressor).

My OS is better than either one of those.....just as transparent......with more sustain...and the cool feature of leaving just a tad of my first click of the pick slightly louder than the other compressors.

The OS with the mods I put in it is definitely the best all round compressor there is.....and mine is not mild compression at all....unless I set the bias pot for a mild setting.

There is more than just the sweet spot that everyone talks about, but to realize the variation you must use a 20 turn pot and the entire variation occurs in about 1/2 turn of the 20 turn pot.

The mods I used can be found herehttp://www.diystompboxes.com/smfforum/index.php?topic=40743.msg298151#msg298151

Those mods will work with any FET or si diodes.   I am going to build another one exactly like this last one.  It works great on vocals too.

I have not tried the Bass Guitar with it yet.

The Orange Squeezer circuit is capable of some real versatile mods.....it can be made to sound way better than the clips at tone frenzy.

[3/4 North]

Are these the mods you mean?

On my OS from GGG..........
D1 is 1N34
Changed C1 to .01uf ceramic.
Q1 and Q2 are 2N5485
Changed C3 to 10uf electrolytic
R7 set at 3.68K
Changed R9 to 200K
Added 51pf ceramic in parallel with R9
Changed R10 to 6.8K
Changed C6 to 1uf NP
Changed R11 to 1K
Changed R12 to 1M
Added 100pf ceramic across pins 1 and 3 of R13 (not the wiper).

I'll give it a try

[krister]

Glad to see you got your project finished up.

I recently made some changes to my multi FX box which my OS is installed in and I do not get any unwanted noise now (I found a loose solder joint and I had some power supply issues that I fixed).

The mods I made to the OS (from reading all of what Mark H and RG have over on GGG) have proved to be very durable mods that give me one of the best compressors that I or anyone else I talk to has ever listend to.

My brother plugged into it and fell in love with it....way better than the compression in his Marshall Stack.

I now have two other compressors to compare it to..(not including the Marshall)...I now have a Digitech RP7 Valve with a excellent compressor and I just bout an RNC (Realy Nice Compressor).

My OS is better than either one of those.....just as transparent......with more sustain...and the cool feature of leaving just a tad of my first click of the pick slightly louder than the other compressors.

The OS with the mods I put in it is definitely the best all round compressor there is.....and mine is not mild compression at all....unless I set the bias pot for a mild setting.

There is more than just the sweet spot that everyone talks about, but to realize the variation you must use a 20 turn pot and the entire variation occurs in about 1/2 turn of the 20 turn pot.

The mods I used can be found herehttp://www.diystompboxes.com/smfforum/index.php?topic=40743.msg298151#msg298151

Those mods will work with any FET or si diodes.   I am going to build another one exactly like this last one.  It works great on vocals too.

I have not tried the Bass Guitar with it yet.

The Orange Squeezer circuit is capable of some real versatile mods.....it can be made to sound way better than the clips at tone frenzy.

Thanks, KMS. Now I just have to record some sounds clips for all to hear. I never turn the OS off, it sounds too good to turn off.

[KMS]

Are these the mods you mean?

On my OS from GGG..........
D1 is 1N34
Changed C1 to .01uf ceramic.
Q1 and Q2 are 2N5485
Changed C3 to 10uf electrolytic
R7 set at 3.68K
Changed R9 to 200K
Added 51pf ceramic in parallel with R9
Changed R10 to 6.8K
Changed C6 to 1uf NP
Changed R11 to 1K
Changed R12 to 1M
Added 100pf ceramic across pins 1 and 3 of R13 (not the wiper).

I'll give it a try

Yes.....but not firm on that R7 value.....set R7 close to 3.68K so you don't have to waist time finding the compression zone if your using a 20 turn trim pot....which I recommend a 20 turn trim pot so you can realize the true range of compression.

Also, like krister, I leave my OS on all the time and thus no bypass is needed which cuts down on extra wires and contacts...... I have the 20 turn trim pot glued/epoxy to the box with a small hole in the box so I can quickly adjust the compression if needed and still not worry about my favorite setting getting bumped.  So if I do not want any compression....I just turn the pot 1/2 turn and I have no compression.

[krister]

How would I post a sound sample here? I don't see an option to attach a file. Thanks.