My OD's cut my amps bottom end

[guitarwreck]

I am so tired of this. I have a Maxon , a Boss blues driver, and behringer To800.

Whenever I bypass them and turn my tube amp up and use it's own preamp to overdrive, it sounds like heaven, fulkl, bottom end.

When I try to use the overdrives, they cut out that rich, bottom end amp sound. There must be an overdrive somewhere that will keep the rich quality of my Tube amp's sound when having it engaged. Can some of you folks give me some suggestions for overdrives that will keep the quality sound of my amp?

[corworld]

When you increase the gain with a pedal you compress the sound more. If you want a big low end you have several options:

1. Dial back the overdrive pedal
2. Try a clean boost pedal instead
3. Get a bigger cabinet

[guitarwreck]

So you are saying that there are no overdrive boxes that keep the bottom end intact? Not even ones that cost $250 bucks? What about ones with tubes in them?

I thought about a clean boost, so that would give me more volume to overdrive my amps own tube overdrive, correct? But, wouldn't that force me to have the volume of my amp boosted up?

On my overdrives I can set gain level and still make the pedal equal volume as if bypassed. But would a clean boost allow for this same level?

[Mark Hammer]

Your problem is your choice of overdrive. All three you mention are decent pedals but basically variations on the same theme.

Here's the thing. The bass signal is always a greater amplitude than the mid and treble signal, simply because thicker wound strings result in more signal being sensed by the pickup. If one is clipping with diodes, it means that the lower notes will always reach the clipping point more easily than the mid and higher notes. Hit a 6-string chord, and the sheer power of the low strings turns what might be a smooth overdrive into a fuzzier tone than maybe you were looking for.

Consequently, a number of overdrives, in their attempt to yield a "smoother" tone, trim back on the bottom end before clipping so that both higher and lower notes are distorted by approximately the same amount. That process produces a lot of treble content, compared to the bass, so the pedals will invariably roll the top off to restore some tonal balance. Unfortunately, they never get the bass back. This combination of factors is responsible for the famous/infamous "mid-hump". That hump has launched hundreds of alternate designs based around the same general strategy, many of which try to introduce a bit more bass without producing harsher bottom end. You can learn more about it at www.geofex.com in the "Technology of the Tube Screamer" article.

One way to retain a bigger bottom end but still get smoother clipping is to split the signal prior to clipping. One copy of the signal gets the traditional bass trim prior to clipping, and the other path is simply the whole signal without any further treatment. The distortion and clean signals are then blended in some proportion prior to output. Voodoo Labs make a pedal called the "Sparkle Drive" that does exatcly this, though I'm sure there are others.

[Jered]

What kind of an amp are you using? And guitar? Singles or HB?

[Paleo Pete]

Might be along the same lines as what Mark posted, but the main issue is that the bass tends to get muddy when you add distortion, so most pedals either cut off the bass frequencies and distort only the mids & highs or roll off the bass so it doesn't project as much, to get rid of the mud. If I understand what I've read correctly that is...but I do know that just my Super Reverb cranked up tends to get muddy by itself if I give it too much bass. That's probably why they try to cut the bass frequencies some, or at least it makes sense to me after hearing what just the amp by itself does...

I've had no problems with my Marshall Bluesbreaker, it seems to sound very good, and the only time I use it is normally with a Fender Super Reverb cranked to full tilt, and I use a lot of bass. (I set my amp for enough bass to sound like a 10 foot bulldog barking behind me and enough treble to cut glass...I want TONE...) I'm currently poking around to find some mods for a Boss DS1 pedal to cut the gain a bit so I can use it as an overdrive in place of the Marshall, since it's been giving me trouble. I'll have to try it out some to see, but I might have similar issues with it, don't know yet. so far it seems to do pretty well, but I haven't tried it with the Super yet, only with a Fender Champ maxed out. So far I've found I can just change one resistor, that might do the trick, I'll keep an eye on what's happening in this thread and see how it turns out. Since the Boss seems to have a pretty decent sound already, it might work, but I may also have to tweak the tone as well, won't know until I look up a bit more info and try it.

[Steve A.]

I am so tired of this. I have a Maxon , a Boss blues driver, and behringer To800.

Whenever I bypass them and turn my tube amp up and use it's own preamp to overdrive, it sounds like heaven, fulkl, bottom end.

When I try to use the overdrives, they cut out that rich, bottom end amp sound. There must be an overdrive somewhere that will keep the rich quality of my Tube amp's sound when having it engaged. Can some of you folks give me some suggestions for overdrives that will keep the quality sound of my amp?

The Visual Sound Route 66 (and Dr Jeckyl & Mr Hyde) pedals use a tweaked TS808 Tube Screamer circuit, but with a switch to engage a bass boost. Typically you might use the boost with an open back cab, while you skip if you were using a closed back back. I believe that the T-Rex Moller Overdrive also has the bass boost.

Steve Ahola

[Mark Hammer]

This device - http://www.pedalgeek.com/cgi-bin/new...and=link--aess - is intended to address the issue of farty bass when there is too much bottom fed to it or to an amp. A number of pedals, already mentioned, attempt to tackle that within the pedal itself. Unfortunately, they allow for little control over how severely that "problem" is attacked.

[Paleo Pete]

Thought of something else last night, I'm wondering where you set your tone knob? I run mine on both SD 9 distortion and Bluesbreaker Overdrive with the tone knob around 10-11:00 position. Same for the Boss distortion pedal, but I haven't used it much, just got it not long ago. That gives me a good sound and none of them seem to "cut" the bass, they simpply don't distort it. Turn it up halfway or more and it becomes a much too treble oriented sound, past about 3:00 and it seems it's all treble. I don't know enough about electronics to have a clue how the things work internally, but I do have good ears that tell me I'm not losing much bass if any.

When using any overdrive or distortion I start with the tone knob around the 8:00 position then turn it up a little at a time until I hear it just start to bring the highs out. That usually seems to be as far as the tone knob needs to go, otherwise I get too much treble, same for the Marshall Bluesbreaker overdrive, tone on it sits about 11:00 I think. I'm wondering if you're setting the tone knob too high, and getting all treble out of your box. The Maxxon should be close to a clone of a Tube Screamer, depending on which model you have, Maxxon made the original for Ibanez and their recent reissue is said to be very close to the original TS 9, one of the best overdrive pedals out there. (My SD 9 is stamped Maxxon inside, so is the dead TS9 I have, and Maxxon is silk screened onto the boards)

Try it and see, it seems my pedals don't actually cut the bass, they just don't distort it, to avoid the muddy sound you get from distorted bass. The Boss hasn't been tried on a full size amp yet, but I'm betting it will get good sound too, it doesn't seem to kill the tone of my Champ. If they do cut the bass, it's not much, I use low notes in solos too and they come out just as well as the highs do onstage.

[pdf64]

The weird thing with TS type circuits is that the clipping is in the feedback loop of a NON Inverting op amp. Therefore the original unclipped signal is always in the mix. That's why the gain formula is the feedback ratio + 1. The '1' is the input signal. With low output PUs, the clipped signal dominates. However, with powerful PUs, you can hear the clean signal underneath, with the clipped signal sitting on top. The bass cut is on the overdrive part of the signal, in the feedback loop, the clean part is flat response.
So if you want the same effect with a strat, try a clean boost before the TS. Peter.

[Mark Hammer]

The weird thing with TS type circuits is that the clipping is in the feedback loop of a NON Inverting op amp. Therefore the original unclipped signal is always in the mix. That's why the gain formula is the feedback ratio + 1. The '1' is the input signal. With low output PUs, the clipped signal dominates. However, with powerful PUs, you can hear the clean signal underneath, with the clipped signal sitting on top. The bass cut is on the overdrive part of the signal, in the feedback loop, the clean part is flat response.
So if you want the same effect with a strat, try a clean boost before the TS. Peter.

Um, I'm not buying it. The bass cut is part of the gain applied to the entire signal. It just so happens that when the amplified signal reaches the forward voltage of the diodes, they conduct too. Normally, it takes a certain amount of gain to bring all portions of a guitar signal up to that critical forward voltage, simply because the signal may well be 200mv initially, but it quickly dies down to 20mv and much less if you're playing single notes on an unwound E. If you have normal pickups, and use a pair of silicon diodes for your clipping, a gain of around 40 CAN be sufficient to introduce momentary clipping on the wound strings, but typically you want a gain of at least 80-100 to start producing clipping that lasts more than a milllisecond or three beyond the start of the pick attack. (Keep in mind that what we hear as "distortion" involves added harmonic content that occurs over enough of the note's lifespan to be of interest. That involves much more gain than what is required to merely have some brief initial portion of the signal reach the critical threshold.) In the case of the TS, that gain of 80 or so is applied to content above 720hz, with less gain applied to content below that corner frequency.

So yes, you CAN always hear the clean signal underneath the added harmonics, but that would be true of just about ANY distortion, especially as the note dies out, and most especially if the fuzz gain is not set to maximum and the device's max gain is not outrageous.

[pdf64]

'The bass cut is part of the gain applied to the entire signal.'
No, the bass cut is applied to the feedback signal.
The unclipped, flat response signal passes straight through the clipping stage - a non inverting amps gain never falls below 1. That's a fundementally different scenario than a regular distortion clipper, such as
http://www.freeinfosociety.com/elect...iew.php?id=562
in which the entire signal is routed via the clipper and the signal level can't go above the clipping threshold. Whereas it can with the TS.
Re signal levels, my scenario was with powerful pickups, and the thread's about bass response, therefore the signal levels will be fairly high. The thing I was pointing out is most obvious on the pick attack and on the bottom end, with humbuckers, where the input signal level will be equivilant to the clipped signal.
Hope that clarifies my earlier post. Peter.

[Mark Hammer]

Okay. That does clear up what you were trying to convey. Of course, the unity gain part is waaaaaaaaaaay in the backgound in comparison to the signal to which gain has been applied. And if one needs to apply a gain of 50+ to even begin to hear any transient clipping, then the bass-cut feedback signal will easily dominate what one hears.

As near as I can figure out, the inherent problem with a number of 70's era clippers like the Distortion+, and DOD250 is that they use a non-inverting configuration, and more particularly that they adjust the gain via the ground leg. The net result is that increased gain will necessarily be accompanied by a cut in bass response.

My sense is that there were several motivations to do this. First, obviously it shifts the emphasis in the signal to the harmonic content, which is what the pedal is intended to do. So the gain control serves as a kind of compensating tone control as well. But I also think that, in an era that preceded the wider range of hum-rejecting options available to single-coil players, one of the secondary goals of that design was to decrease the audibility of that portion where the hum resided as one turned up the gain. In other words, if someone was playing a Tele at high volume, applying a gain of 200 to 60-cycle hum was simple bad practice. So, as more gain was applied, less was applied to the hum by gradually raising the low-end corner frequency. With a low-end rolloff starting around 720hz, and a 6db/oct slope, 60hz hum would be 2.5 octaves lower than the rolloff, hence have 15db less gain applied to it. Not perfect, but close enough for rock and roll.

[imaradiostar]

I think the original poster needs to check out a few pedals with better post distortion eq. I'd recommend the SIB Varidrive, Menatone King of the Britons, or even the runoffgroove.com Thor pedal as an excellent but simple pedal with a built in bass boost. You should be able to buy a kit for the Thor if you don't feel like building it from scratch.

I think that full distortion sound relies on slightly attenuating the bass and often some treble so that the mids are more prominent and distort more while the bass remains cleaner, preventing a "flabby" or "farty" distortion due to the bass blocking the other frequencies. In most decent "distortion" amps (with exceptions- trainwreck, for example) there is a tone circuit of some kind after the distortion that matches your particular tastes and style of music. Picture scooped mids and boosted bass and treble for that mesa dual rect sound and more prominent midrange for a marshall "brown sound." Also keep in mind the mesa alters the negative feedback in the power section...too many varibles to duplicate!

jamie

[Chevy]

To original poster:

Try a new Danelectro Cool Cat Transparent Overdrive pedal.

It's not perfect, but I'm getting great bottom end out of it. It has separate bass & treble controls, which is great. No mid hump, and the pedal is actually quite transparent. The cost is minimal.

The drawback I'm finding, and have found in other pedals, is that when I dig into a note, the pedal will just clip at the set level, and compress the signal from there on up; but I want to hear the full "clean" dynamics/harmonics of that note, PLUS some overdrive. It seems that the design of pedal I need is like a Sparkle Drive or a Moller to get what I want. Except the SD has a mid hump. The Moller is not true bypass. Sigh....