Big Tube Screamer Debate

[soupbone]

I posted a question on another forum,that I won't mention.There's some people saying on my post that there's no audible difference between a TS808-TS-9-TS-10.Really?Some said changing the 2 resistors in the TS-9 does nothing sound wise.Anyone have any opinions on this?I've been playing guitar for almost 30 years,and I have to say there is definitely an audible difference,or am I just deaf?lol

[karbomusic]

Rewriting because I misread.  I dunno, I never cared enough to compare them. I love the TS circuits I've designed but never been a big fan of the store bought ones everyone raves about.

[FiveseveN]

RG has of course covered this, and the issue at hand is discussed in the Output Buffer Stage section: http://www.geofex.com/article_folders/tstech/tsxtech.htm#obuffer

[mremic01]

http://www.beavisaudio.com/projects/ScreamerLab/

^ Beavis doesn't hear a difference. Neither do I do. I put those resistors on a DPDT a while back and it really is a useless mod.

If you demo a TS9 against a TS808, either unit is like to sound different due to its components' tolerances. It's easy to attribute the difference to the output resistors, when tolerance is really the factor at play.

[soupbone]

RG has of course covered this, and the issue at hand is discussed in the Output Buffer Stage section: http://www.geofex.com/article_folders/tstech/tsxtech.htm#obuffer

Well,I have known to be wrong a time or two,and this is one of those times. I've read that article before,but not thoroughly.My apologies!You were correct.

[JohnForeman]

I have a TS that I built from the tonepad pcb. I installed the 808/9 mod switch. I can hear a difference when I flip the switch. Maybe I built mine wrong.   

[soupbone]

I have a TS that I built from the tonepad pcb. I installed the 808/9 mod switch. I can hear a difference when I flip the switch. Maybe I built mine wrong.  

I don't know.According to R.G. Keen's site,and others,that there's no audible difference with those resistor changes.Maybe it's my brain tricking me to think that they're two different pedals(well,not really.lol) and that they'll sound different.Which makes me wonder why folks that are the leading pedal modders(i.e. analogman,keeley,etc.) even do this mod,if there's no audible difference?Not trying to ruffle feathers.Just curious.

[diydave]

Is there a significant audible difference in a real live-band situation?
I've never owned, our heard (up close) a "real" tubescreamer. So maybe I'm not in the position to say anything about it.
But I doubt you'll be able to say "ahaaa, that gitarist is using a ts808" or "ouch, the band plays with ts9".
I'm pretty sure that it is a trick of the brain: there is a physical difference therefore we (need to) hear a difference.
And since hearing is mostly a brain-thing...
We mostly don't play in super isolated and acoustic sterile environments as well...
But then again, maybe I'm just babbling and making myself silly 

[slacker]

Everyone knows a TS808 has more mojo than a 9, that's probably why most people do the mod. However, as R.G explains the two buffers will behave a bit differently and some people might be able to hear this.

[mremic01]

I have a TS that I built from the tonepad pcb. I installed the 808/9 mod switch. I can hear a difference when I flip the switch. Maybe I built mine wrong.  

I don't know.According to R.G. Keen's site,and others,that there's no audible difference with those resistor changes.Maybe it's my brain tricking me to think that they're two different pedals(well,not really.lol) and that they'll sound different.Which makes me wonder why folks that are the leading pedal modders(i.e. analogman,keeley,etc.) even do this mod,if there's no audible difference?Not trying to ruffle feathers.Just curious.

If you keep reading:

"However, the 10K shunt resistor load on the TS808 output does have an effect on the follower's operation. An emitter follower with a resistor load is often assumed to have a very low output impedance, which is true, as long as the signal is going up. However, when the signal is going down, the transistor can only turn off, and the signal is pulled down by the net loading, DC and AC on the emitter. The 10K shunt resistor effectively halves the emitter loading on the output buffer. This does two things; trivially, it reduces the input impedance of the emitter follower; more importantly it reduces the negative going output impedance of the stage by half to about 5K. This means that the output stage can drive the following stage off about twice as hard.

"Can this account for the admittedly very subtle audible differences between the TS 9 and 808? It pretty much has to, as the operating current for both stages is the same, the series resistance is only trivially different compared to the forward biased input impedance of a triode grid (10's of K's for the typical duotriode input), and the voltage divider ratio difference between 100/10K and 470/100K is 0.990099 versus 0.995322, an inaudible amplitude difference. "

But RG assumes that the 808 and 9 sound different, even if it's a subtle difference. I hear no difference, not even a subtle one, when the those two resistors are placed on a switch and everything else in the circuit is kept the same. Now I haven't gone around trying it with various amps, but the input impedance of your amp might be a factor. I used to have some Boss pedals with crappy tone sucking buffers that only tone sucked in front of cheap SS amps. Their buffers were transparent in front of nicer tube amps.

[slacker]

To get a difference you probably need to max the volume of the pedal and hit it with a loud signal. If you get a large enough signal going into the buffers the TS9 one will distort on the negative half of the signal before the 808 one. I don't know how easy it is to get this to happen and even if you do I don't know how easy it is to hear it.

[soupbone]

I've learned a lot of stuff from this post.Good stuff fellers!

[Electron Tornado]

"Can this account for the admittedly very subtle audible differences between the TS 9 and 808? It pretty much has to, as the operating current for both stages is the same, the series resistance is only trivially different compared to the forward biased input impedance of a triode grid (10's of K's for the typical duotriode input), and the voltage divider ratio difference between 100/10K and 470/100K is 0.990099 versus 0.995322, an inaudible amplitude difference. "

But RG assumes that the 808 and 9 sound different, even if it's a subtle difference.

I'm not sure that R.G. is stating that the two pedals sound different, just that those two components are the only thing that could account for any tonal difference that might be present.

I've had a number of TS9s, TS808s, and a TS7 on my bench. My own TS808 is one I built from a kit and is true bypass. I've never heard a difference between any of them. I suspect that any audible difference (assuming same guitar, same player, same amp, etc) is due to component tolerances - especially the pots, and a bit of imagination.

Is it just me, or does it seem like most of the folks who make claims about the great tonal differences are usually trying to sell you something?

[Mark Hammer]

I suspect we are basically talking about an output impedance thing, where the sound of the TS is smoothed out by cable capacitance taking out any fizz.  IN other words, loading under certain particular circumstances.  If this was true, then one would predict that a 9 and 808 would sound a little different if you were running a 25ft cable from the pedal to our amp, and feeding a TS of either type directly to another on your boad pedal with a high input impedance (e.g., a Super Hard-On or similar) would not be easily differentiable.

[J0K3RX]

It really is more evident depending on how you use the TS pedals... If you use a TS to tighten the low end attack and and give a little extra boost/sustain in front of a medium or high gain amp then you should be able to hear the difference between the different versions.  Typically this is done by turning the level anywhere from 1/2 to all the way up and the gain between 0 and 2. This way it just overdrive the hell out of the amp input and gives you a razor sharp attack when using a high gain amp.

Now, if you are using it for your main source of distortion you would probably have the gain turned up 3/4 ot the way and the level backed off to a low setting... This way sounds different and reacts totally different. In this way you may not notice a big difference between one TS or another... or maybe you will? Depends on the style of playing and of course, your ears. For me the TS808 or close variant is my choice but the TS9 is also very good...

[FiveseveN]

Let's use the power of Math! (Click the thumbnails to embiggen.)



And into a typical tube amp input, even with ridiculous cable capacitance:


Is there a difference? Sure, a .1 dB difference! If a human can hear that then ESP is real.
What about the output impedance? It's around 1.2 K (in the 808) vs. 1.7 K. Even if you were plugging it into a Fuzz Face for some reason, the difference is still sub-dB.

[Mark Hammer]

Then assuming there IS an audible difference, under some unspecified set of circumstances, maybe its a component-tolerance related thing.

As I like to point out, many folks will make comparisons between different issues of a given pedal, or different manufacturers of the identical design, using only one pedal to represent every instance of that issue or manufacturer.  That's a thin branch to walk out on.

[teemuk]

Then assuming there IS an audible difference, under some unspecified set of circumstances, maybe its a component-tolerance related thing.

As I like to point out, many folks will make comparisons between different issues of a given pedal, or different manufacturers of the identical design, using only one pedal to represent every instance of that issue or manufacturer.  That's a thin branch to walk out on.

Not to mention, majority of comparisons are made solely by ear with long intervals between each test. (It's not uncommon that folks spend several minutes or even hours making modifications before A/B'ing the "B" after "A". Or something along those lines). This practically ensures that each individual will have different results, which are mostly just subjective preferences based on evaluating something we no longer even remember accurately.

And if the audible differences are "subtle" then do keep in mind that you better not...
- move away one inch from your listening position
- tilt your head
- have any kind of stress, muscle tension in the neck area and so on
- have time delays longer than few seconds between A/B'ing
- etc.
...otherwise you already introduce large enough differences to render any evaluation by ear useless. Ears + brain processing what we hear is usually the very best instrument to use when you want totally inconsistent results. ...or just any result of your preference. Believe firmly enough and the brain will make sure you will hear whatever you want to hear.

[karbomusic]

under some unspecified set of circumstances

I don't see how that couldn't be the case. Of the number of guitarists using TS's, and their settings, config, gear and even perception of how it should be used, the combinations are going to be incredibly enormous if not potentially infinite. Who knows under which of those circumstances something shows up on the audial radar. That of course doesn't cover the OCD types who say they can hear the difference using any combination. Just pointing out there could be some who really do and it's based entirely on how they use it.

OT but just to show how much the communication of it all could come into play. I sold a fuzz I built to a friend on Saturday, I told him many times. Make sure you plug your guitar directly into this box, it and the guitar sort of become the same circuit (in guitar player lingo) and it will NOT sound like it does now if you do not do that.

He calls Sunday... "This thing is broken, it sounds nothing like it did in your studio yesterday". I said did you plug your guitar directly into it like I showed you?" He exclaimed and I quote:

"Yes, I did exactly that, I placed it right after my volume pedal".  

[Mark Hammer]

Well that's just it.  The number of possible permutations and combinations IS darn near infinite.  And when players make a claim about a pedal without specifying what the circumstances were when that putative difference was heard, AND the claim hits the internet, it gets attributed to any and all sets of circumstances.