Favorite way to achieve smooth breakup???

[Bill Mountain]

Like many of you, I have built/played plenty of awesome overdrive and distortion pedals and I have been happy with most of them.

What I have a problem with is getting the initial breakup to be as pleasing as full bore distortion.  It's either too splatty or too sharp.  I know we have all experimented with "tubey" breakup but even all the FET's and opamp Tube emulation circuits lack that initial smooth breakup that I'm looking for.

I guess I wanted to get your ideas for smoothing out that initial breakup.  Multiband distortion looks promising, FET's sound great, CMOS is wonderful, etc. but I haven't heard a smooth enough breakup for my tastes.  Maybe my expectations are too high???

Full disclosure:  I play a high-output-low-tuned-bass which is definitely a part of the problem.

[Mark Hammer]

Conceivably your "problem" is dynamics.  Specifically, that initial transient is simply way too much for the pedal.

The "cure" would likely reside in two places.  First, the pedal you use to provide said breakup may need to have a higher supply voltage to be able to better handle those transients.  Second you may wish to have some sort of either compression or peak limiting before the breakup stage.  Indeed, you'll find that some compression prior to an overdrive will tend to even out the tone and make those initial peaks a little less ragged.  In some playing contexts, that's an annoyance, where in others it can make an overdrive more tolerable.

[Johan]

Did you try my pp-driver.  Push pull tube o.d. ?
All the  way from clean to mid/High gain.  Responds very much like a real amp because it is set up like a real amp in a stompbox format.  Preamp. Phase inverter. Power tubes (well. Two sides of a 12au7)with negative feedback.  low part count. Easy to build. Safe voltage. I remember you responded to the thread, so did you try it?
J

[Bill Mountain]

Conceivably your "problem" is dynamics.  Specifically, that initial transient is simply way too much for the pedal.

The "cure" would likely reside in two places.  First, the pedal you use to provide said breakup may need to have a higher supply voltage to be able to better handle those transients.  Second you may wish to have some sort of either compression or peak limiting before the breakup stage.  Indeed, you'll find that some compression prior to an overdrive will tend to even out the tone and make those initial peaks a little less ragged.  In some playing contexts, that's an annoyance, where in others it can make an overdrive more tolerable.

Agreed.  I have thought a lot about upping the supply voltage but on this very forum it was suggested that I just turn down a little.  I've tried it both ways but I haven't come to a conclusion yet.

I have a experimented with a compressor first in my chain (simple Dynacomp) but it generated too much noise.  I should try again with a better comp.

I will give the higher voltage thing another look.  My baseless theory for why bass signals don't clip as smoothly as guitar signals is because the order of magnitude difference between bass and guitar is far higher than most pedals can accommodate.

I've always wanted to make a 60V fuzz face to test my theory but it's always been so far down on my to-do list.

The project on my breadboard at the moment splits the signal after a 20dB CMOS boost into diode clippers and a LPF and I recombine then with a simple passive mixer.  It sounds great with the gain maxed but it is super farty at low gain which is what inspired me to post this thread.  I'm going to redesign it with the diode side getting high passed at 100Hz or so and using an active mixer to see if that improves anything.

[Bill Mountain]

Did you try my pp-driver.  Push pull tube o.d. ?
All the  way from clean to mid/High gain.  Responds very much like a real amp because it is set up like a real amp in a stompbox format.  Preamp. Phase inverter. Power tubes (well. Two sides of a 12au7)with negative feedback.  low part count. Easy to build. Safe voltage. I remember you responded to the thread, so did you try it?
J

I was intrigued by the design but It seemed overly complicated for what it achieved and input sensitivity on starved plate designs is extremely low in my experience.  And I prefer low current designs.  I'm like the only person left who prefers batteries.  Maybe I should look at it again.  I had also considered doing P-P clipping with CMOS stages too.

The best tone I got was using my buddy's Laney into a Palmer PDI-03 into my bass amp.  I loved it but it was excessive to say the least.

Maybe I should build a tube amp and a power soak/cab sim into a rack and drag that to gigs with me!!!

[Mark Hammer]

I can't link to it here, from work, but if you go to this thread you'll see the schematic from the old Electronic Musician construction project article.  http://www.diystompboxes.com/smfforum/index.php?topic=100619.0

Bill cleverly used the LEDs in an optoisolator (vactrol) for clipping, but used the LDR sections for compression in an earlier stage.  Maybe you want something like that?  Since the compression kicks in at the point where the clipping commences, maybe that can smooth things out to your liking/needs?

[stallik]

No real science to this suggestion but I'm currently using a spitfire set to a gain of about 75% and with the output volume well above unity going into a tube amp. That should give me a big rock sound and it does unless I turn the guitar volume down. Right down. Beautiful smooth clean with guitar on 2 and a light touch through lovely breakup, smooth overdrive and flat out distortion. Only issue is a bit of background noise.
No idea if it would work with your setup but it cost nothing to try

[Bill Mountain]

No real science to this suggestion but I'm currently using a spitfire set to a gain of about 75% and with the output volume well above unity going into a tube amp. That should give me a big rock sound and it does unless I turn the guitar volume down. Right down. Beautiful smooth clean with guitar on 2 and a light touch through lovely breakup, smooth overdrive and flat out distortion. Only issue is a bit of background noise.
No idea if it would work with your setup but it cost nothing to try

How clean is the tube amp?

Most bassists don't get the luxury of power tube distortion to make average pedals sound glorious.  All the drive sound has to come from the pedal.  The amount of pedal demos (for guitar pedals that I want to try on bass) that go into distorting tube amps drives me nuts!!!  Don't get me started on how most bassists are satisfied with pedals that sound like a bag of farts.  Either I'm crazy picky or bassists in general have low expectations for drive pedals.

[midwayfair]

I can't link to it here, from work, but if you go to this thread you'll see the schematic from the old Electronic Musician construction project article.  http://www.diystompboxes.com/smfforum/index.php?topic=100619.0

Bill cleverly used the LEDs in an optoisolator (vactrol) for clipping, but used the LDR sections for compression in an earlier stage.  Maybe you want something like that?  Since the compression kicks in at the point where the clipping commences, maybe that can smooth things out to your liking/needs?

Also, I did something similar with compression + OD without a vactrol in this, which was based on Aquataur's mods to the ROG Umble:

http://www.diystompboxes.com/smfforum/index.php?topic=106453.0

I don't think "smooth breakup" means the same thing to everyone. I consider it to be that it's controllable with playing dynamics whether you get distortion, which requires a wide dynamic range. Some people consider it to be that you get a very consistent amount of distortion through, which requires a minimal dynamic range (i.e., compressed).

[Bill Mountain]

Good point about defining smooth breakup.

What I'm referring too is the threshold from clean to dirty is not sputtery, splatty, glitchy, ugly square wavey, etc.  The compression of hard distortion can lead to a smoothness but crossing over into that always sounds....um.......not as good.

[Hemmel]

(...) about defining smooth breakup.

I usually call her while drunk and crying, telling her that she's too good for me and I'm pulling her back.

Usually works smoothly.

[sajy_ho]

(...) about defining smooth breakup.

I usually call her while drunk and crying, telling her that she's too good for me and I'm pulling her back.

Usually works smoothly.

Build the Mad proffesor's "Stone Gray Distortion"

[stallik]

how clean is the tube amp

Totally, squeaky clean. Think albatross. All the distortion comes from overdriving the input a little and the pedal itself.