What The Hell Is Diode Clipping????

[joshuaaewallen]

I'm as fascinated about the components that go into getting your ultimate tone as anyone else here, but in the end equation... Since music really is all about our ears, then what really matters is if the tone gets our juices flowing... Regardless of what it takes to get us there.

Personally... With or without diode clipping and pedals, nothing floats my boat like the roar of a good Marshall tube amp. Long live Rock & Roll!

 

[steelhorse]

I applaud you joshua! heh

 

[Adwex]

Not sure if this helps the discussion, but here are my observations.....

I've owned two Marshall heads (and a rack rig, but that doesn't apply here).

My first tube Marshall was a JCM 900 50 watt dual channel head. It had diode clipping.
It sounded like crap...very "grainy" distortion, with no low end whatsoever.

My second, and current Marshall is a 2555 100 watt Silver Jubilee. It has diode clipping.
It sounds great...smooth distortion, with that "hollow" attack, almost 3D sound. I've been told to "turn down the bass".

 

[Hollowbody]

I have owned an 800 a 900 and a Jubilee 2550 50 watt head. The only one I have now is the Jubilee. They all sounded really good. On the Jubilee you can switch the diodes in or out. There are times when I hear the harsh sound when the diodes are switched in on the rythm clip.

I am doing some research on mods for the clipping circuit, and I completely agree with Josh.

 

[Hollowbody]

Where is it?

 

[Hollowbody]

oh, sorry. it's there.

...Geez

I'm new at this, can you tell?

 

[HOT TUBES 70]

I have owned an 800 a 900 and a Jubilee 2550 50 watt head. The only one I have now is the Jubilee. They all sounded really good. On the Jubilee you can switch the diodes in or out. There are times when I hear the harsh sound when the diodes are switched in on the rythm clip.

I am doing some research on mods for the clipping circuit, and I completely agree with Josh.

by changing the diodes to different values etc, you radically change the
personality of an amp , i had a 2205 and all i did was change the diodes
to a pair of 1n34a germainiums and it instantly changed the "buzzy"
distortion to a sweet warm distortion that was nothing like itself before.

so it depends on the amp in question i guess .

 

[steelhorse]

by changing the diodes to different values etc, you radically change the
personality of an amp , i had a 2205 and all i did was change the diodes
to a pair of 1n34a germainiums and it instantly changed the "buzzy"
distortion to a sweet warm distortion that was nothing like itself before.

so it depends on the amp in question i guess .

It makes logical sense HT.

According to the dude I got the Dual Recto from he asked the Mesa tech he wanted more gain and depth but wanted it to be tight and apparently the tech replaced 1 or 2 of the diodes and he said it made a noticeable difference. He's had the amp for almost 13 years then he decided he wanted a Marshall and that's how I wound up with it.

 

[DrVintage]

What I find quite funny is how people will absolutely say how tube overdrive is the best and all sorts of stuff like that, then have no qualms about sticking a bunch of solid state overdrive and distortion pedals in front of their amp. So you've got an all tube cascading gain circuit and you stick a tubescreamer in fron of it to tighten it up or push it that little bit more. So yeah, why not put one directly inside the amp?

For every type of pedal has it's own characteristics, combined with the tube warmth.
If i play on my 6100LE with TAD's as outputs, i prefer for a slightly bluesrock style my A-Man TS808 Brown mod on the clean channel, it gives me a crunch i can't get with tweaking the crunch channel (2) or the lead (3) alone without the effect.
It is all in the most preferred coloration in combination with the tube saturation (that even an overdrivecircuit inside the amp can't give me)
______________________________________

If i am happy about the sound, so are they!

 

[DrVintage]

Damn, sorry i'm a bit late with that comment, but what i mean=:
it's all in the spices you add (ss or tube no matter what), that form the taste.
I have some modded pedals i really like using in combination with my tubes, but also i always use a tape delay (RE-201) and it gives me more than the SDD2000's i have.
So the preferred coloration is determined by the complete signal channel, and not only by an amp,guitar,or fx.
_______________________________
If i am happy about the sound, so are they!

 

[coldsteal2]

What about those of us who do all these things you described, or at least pay close attention to an amp on component level and are stringent with the rest of our signal chain and DON'T put a buch of transistor stompboxes in front of our rig and STILL bitch about diode clipping?

(In a 900 or otherwise)

well they wouldnt be the ones that i would be talking
about

 

[Hollowbody]

Thanks Hot Tubes, you just clairified for me which diodes I should try. I had even posted that part number some where else in a different conversation but wasn't completely sure.

I realize the change won't be identical due to many factors and tolerances but it is a start. The problem I was running into was something I had read about germanium diodes having a lower threshold which would mean harder clipping, which, in a SS circuit (or in this case the solid state part of a tube circuit) sometimes translates into a fizzy sound at higher imput levels but I am running at a lower gain with passive PU's and a 12ay7 in my first slot I should be ok. I guess I could by a bunch of diodes and sort them out and run some well marked alligator clips out of the chassis and try them all. I know I would have to make sure my amp was off each time.

You are right Cold Steal2. I figure I can only bitch about my own amp without asuming everyone else is having the same problem.

Crap, now I have to go and drain my filter caps again, never any time these days for practise.

 

[Adwex]

I have owned an 800 a 900 and a Jubilee 2550 50 watt head. The only one I have now is the Jubilee. They all sounded really good. On the Jubilee you can switch the diodes in or out. There are times when I hear the harsh sound when the diodes are switched in on the rythm clip.

I am doing some research on mods for the clipping circuit, and I completely agree with Josh.

I recently was told by someone I trust that the diodes are always in the path, even without the rhythm clip pulled out. Apparently you can see the LED's lighting up if you play the amp with the chassis removed from the box.

By the way, I NEVER use that rhythm clip thing...sounds awful to me.

 

[Hollowbody]

Yeah, the rhythm clip is a cool idea but I have been rolling off my GTR volume to accomplish the same thing. I thought the rhythm clip was the only part of the amp that used that set of diodes, I need to take another look at my schematics.

If I do get this done and it sounds good enough I will see if I can put a relay in and make it footswitchable. I could have all three settings available on the floor. My amp tech said that the 800's use a relay and the 900's use a transistor for channel switching..

I wonder if there is anyway to replace a diode clipping circuit with a tube driven clipping circuit. I guess there would have to be enough room in the chassis and a way to run the heater power and all the peripheral components. If it were possible I would be tempted to try different tubes, maybe an EF86, or who knows.

I know I should turn it over to my amp tech but if I do then I won't learn. He is very generous with his knowledge and an all around cool guy but I need more hands on. He will probably slap down this crazieness, like the time I suggested a footswitchable bypass for the tonestack.

I know I am dragging this on but, My perception of how my amp sounds is not based on any terminology, it is based on what I am hearing. I could care less about the stigma behind the use of tubes or diodes. Believe me, if I could shove a stuffed beenie baby toy, or maybe put or a burrito in the socket and make it sound better, I would be making daily trips to Taco Bell.

...time for lunch, later.

 

[Adwex]

HAHA, "the beanie baby/burrito mod".
Those things sound awesome LOL.

 

[sinrman68]

I know that this is quite a touchy subject. I haven't cranked a JCM900...but at showroom volume, the ones I've tried all sounded awesome. I will say IMO that it depends on the power tubes. I had a Carvin Belair and it used diodes in the drive-and 4 EL-84's. I didn't like it at all...too smooth and compressed...no dynamics-just flatlined. I've been told that the mod's to remove the diodes from that circuit are pretty popular. The question-why add diodes to a country and western amp???

 

[coldsteal2]

i think my 900 sounds great

 

[HOT TUBES 70]

Thanks Hot Tubes, you just clairified for me which diodes I should try. I had even posted that part number some where else in a different conversation but wasn't completely sure.

I realize the change won't be identical due to many factors and tolerances but it is a start. The problem I was running into was something I had read about germanium diodes having a lower threshold which would mean harder clipping, which, in a SS circuit (or in this case the solid state part of a tube circuit) sometimes translates into a fizzy sound at higher imput levels but I am running at a lower gain with passive PU's and a 12ay7 in my first slot I should be ok. I guess I could by a bunch of diodes and sort them out and run some well marked alligator clips out of the chassis and try them all. I know I would have to make sure my amp was off each time.

You are right Cold Steal2. I figure I can only bitch about my own amp without asuming everyone else is having the same problem.

Crap, now I have to go and drain my filter caps again, never any time these days for practise.

Also , if and when you find your clipping diodes , try and put 2 or 3 in series
but start with one and work your way up , my 2205 needed 2 inseries to make
it sound good , and what i mean by good is ......WARM TUBES if you know
what i mean , i'm going to also try this on my 6100 LM amp !!!

good luck !!

 

[joshuaaewallen]

steelhorse - I know you weren't singling out the SL-X, that was actually a nice highlight. I didn't know Kiss used them, I thought they weren't very reliable when used hard. A bridge rectifier or something like that tends to over heat & burn out? So far no probs with mine with moderate use. And you're right, the JCM 900 detractors nock them all.

5er driver... You have the best avatar ever!!!

Rock on!

 

[Bunnest]

DIdn't Jason Becker use a 900 on DLR Skyscraper? If he used it, Im sure it has mass potential. Plus, that tone he got, feels like paradise or something, sounds nice and classic-open sounding in the intro, open chordal tones, very early marshall sounding