What The Hell Is Diode Clipping???? - Page 3

steelhorse · 10-15-2008, 02:24 AM

I didn't realize KISS was so disrespected.

5er driver · 10-15-2008, 02:41 AM

Quote:

Originally Posted by coldsteal2

They buy reissue guitars, with vintage pickups,
wiring, capacitors and pots, NOTHING ELSE WILL DO.
Then have to have a vintage tube amp or reissue amp (PTP or nothing)
then put 25 transistor stomp boxes in between their guitar and their
vintage amp then whine about a diode in a 900.....

That's a classic! I know several people in that category............

coldsteal2 · 10-15-2008, 02:49 AM

dont get me wrong, i love reissue guitars with vintage
pickups, capacitors and pots, and ptp vintage amps.

5er driver · 10-15-2008, 05:02 AM

Me too, but this is a killer line: "then put 25 transistor stomp boxes in between their guitar and their vintage amp then whine about a diode in a 900..... "

codyfarmer · 10-15-2008, 08:41 AM

This is a very good thread +1

DragonSarc · 10-15-2008, 09:04 AM

^----------- + 1 I miss my 900 shouldnt have sold it

travismbrown · 10-15-2008, 10:31 AM

How easy would it be to remove diode clipping from my 900 dual verb 100 watter?

How dramatically would that change its tone?

***Adwex*** · 10-15-2008, 10:36 AM

Quote:

Originally Posted by sojatriani

The 4500 is garbage, OK...

The 900 series diode clipping heads are the best sounding JCMs in my opinion. I'll take a 4500 anyday over any DSL/TSL or 800. Don't disrepect the 900. ZZtop used them on the Recycler Tour, I don't think they would take junk on the road with them.

Maybe I got a bad one. All I know is that mine sounded terrible. Putting an EQ in the loop with the low end boosted helped alot, but it still sounded harsh, and "grainy". Maybe it was the stock tubes, who knows, I'm just glad it's gone.

Maybe an attenuator would've helped, it did sound better loud.

stock_hippie · 10-15-2008, 10:56 AM

gotto get a SL-X!!!

sojatriani · 10-15-2008, 03:01 PM

Quote:

Originally Posted by travismbrown

How easy would it be to remove diode clipping from my 900 dual verb 100 watter?

How dramatically would that change its tone?

If you use the first channel there is no diode clipping, only channel two.

steelhorse · 10-15-2008, 03:12 PM

Quote:

Originally Posted by stock_hippie

gotto get a SL-X!!!

you sure do!

HOT TUBES 70 · 10-16-2008, 10:24 PM

speaking of killer sounding marshalls has anyone played the kerry king amp?

stock_hippie · 10-16-2008, 11:25 PM

you take your diode to the shoppe...you have her take a seat... and look thru the book and pick a style...you say youll be back in an hour..when you return.pay and dont forget to say how good she looks.......lol

Shawn Fate · 10-18-2008, 09:15 AM

Amplifier overdrive and distortion is usually achieved by signal clipping,pushing the gain until the signal peaks are chopped off. "Real" tube overdrive isn't possible without major changes (adding additional preamp stages, etc.)

Preamp clipping can be simulated by installing a diode-clipping circuit.

More ballsy sound (especially at low volumes.) In theory, diodes conduct current in only one direction. But they don't operate "perfectly." All diodes have a "forward voltage" they won't conduct until that voltage is reached.

If a diode is connected between the signal path and the ground, the signal won't be channeled (shunted) to ground until it exceeds the forward voltage. And even then, the whole signal isn't dissipated, only the portion of the signal above that forward voltage. So it's peaks are simply "chopped off."

But it also results in more attenuation, as some of the signal is lost. That isn't all bad. Clipping the loudest parts is also a form of "limiting" you loose some dynamics, but accentuate the lower-volume sounds.

Plus, many amps don't begin to distort until turned up too loud for many venues. Like a stomp-box, diode-clipping lends a killer sound at a lower volume.

asymmetrical clipping, offers the most natural and "tube-like" sound. Plus, it's the most flexible--any number of diodes in series can be used to shape the effect.
Germanium diodes tend to have softer transitions which give a non-linear, more "tubey" sound. But silicon diodes can give a sharper "square wave" metallic distortion, if that's your thing.
MOSFET transistors and Zeners can also be employed to establish higher clipping thresholds.
You can even use LEDs as clipping diodes. Marshall MGs use those.
Many players call all 2203 style master volumes JCM-800's, but these 2203 amps were being made long before Marshall began calling their amps JCM-800's. Also, there were JCM-800's being made which used diode clipping, and thus were not the older style 2203 circuit.

Early JCM-800's with diode clipping
in----G1---EQ---gain---G2---DIODES---volume--G3--loop--Phase Inverter---master volume--->
This complex circuit was Marshall's first attempt at mixing tube and transitor distortion in its larger amplifiers. The mix of tube gain and diode clipping produced more distortion, but some players thought the sound was too "buzzy" and "thin" and "cold" compared to Marshall's all tube designs.

Later JCM-800's, and JCM-900's with diode clipping (diodes in rectifier circuit)
in----G1---------volume----G2---DIODES----G3-------------------------EQ---master volume--->
Marshall refined the concept in its late JCM-800's and JCM-900's. Using solid state diodes is a lot cheaper than adding new tube gain stages, and many of the new hard rock and metal players were beginning to appreciate the harder sound of these amps.

PaoloJM · 10-18-2008, 01:04 PM

Quote:

Originally Posted by Shawn Fate

Early JCM-800's with diode clipping
in----G1---EQ---gain---G2---DIODES---volume--G3--loop--Phase Inverter---master volume--->
This complex circuit was Marshall's first attempt at mixing tube and transitor distortion in its larger amplifiers. The mix of tube gain and diode clipping produced more distortion, but some players thought the sound was too "buzzy" and "thin" and "cold" compared to Marshall's all tube designs.

Later JCM-800's, and JCM-900's with diode clipping (diodes in rectifier circuit)
in----G1---------volume----G2---DIODES----G3-------------------------EQ---master volume--->
Marshall refined the concept in its late JCM-800's and JCM-900's. Using solid state diodes is a lot cheaper than adding new tube gain stages, and many of the new hard rock and metal players were beginning to appreciate the harder sound of these amps.

I, for one, have yet to see or hear of a JCM 800 that has/had a diode clipping circuit as part of the original circuit. The only "stock" diodes in these amps that I am aware of are in the HT and bias supplies.
Many have been modded with clipping circuits all right.
The 900 series is the first Marshall amp that used diode clipping AFAIK.
The rest of your info is spot on though.

Shawn Fate · 10-18-2008, 01:14 PM

JCM 800 model 4210 and model 2205 both use diode clipping.
Models 2210 and model 4211 have extra tube gain stage after the diode clipping. The diode clipping itself had been altered to a more complex arrangement-more like a diode bridge rectifier, and the EQ was repositioned to after the third gain stage. Much like the 2203 amps.

MKB · 10-18-2008, 01:16 PM

Quote:

Originally Posted by PaoloJM

I, for one, have yet to see or hear of a JCM 800 that has/had a diode clipping circuit as part of the original circuit. The only "stock" diodes in these amps that I am aware of are in the HT and bias supplies.
Many have been modded with clipping circuits all right.
The 900 series is the first Marshall amp that used diode clipping AFAIK.
The rest of your info is spot on though.

The JCM800 model 2205 and 2210 both have diode clipping, as well as the 3203 Artist 30W. Also the model 2555 and 2550 heads (basically a Jubilee) have diode clipping. These are just heads, the corresponding combo amps have the diode clipping too.

For some reason Marshall went nuts with diode clipping as soon as they started embracing channel switching. Marshall seemed to have a desire to never put more than 3 tubes in a preamp for much of the eighties and nineties. They use the LED method in a few amps and pedals (Jubilee and Guv'nor respectively), but are also quite fond of using bridge rectifiers with the + and - pins connected with a diode. This basically gives you the effect of three rectifier diodes in series, for a 2.1V clipping level. The 2205 and 2210 heads use the bridge rectifier method.

Many of the recent Marshall tube amps do not have diode clipping however.

Shawn Fate · 10-18-2008, 01:20 PM

I forgot about the 3203..jubilee was already talked about so I did not bring it up.

PaoloJM · 10-18-2008, 01:47 PM

Well that's my new thing learned for today!!

HOT TUBES 70 · 10-18-2008, 03:05 PM

Shawn fate ..... great overview of diode clipping 101 , i mod various pedals
on the side mostly just for fun , i have changed the clipping diodes in a few
marshalls , and it makes a big difference , this is a simple mod that costs
very little that gets great result . the break point of the 1n34a germainium
makes it the warmest sounding diode ,but takes away a small amount of
gian , but by adding 2 or 3 in series the gain reapears and sounds killer .
i have also tried mixing all types of diodes for various sounds , the clipping
path can be alterd also with small value caps across the diodes . these are
just some of the tricks that amp mod guys use to make your marshall come
alive . and again great info about clipping -SHAWN FATE

Mats A · 01-14-2009, 06:10 PM

Quote:

Originally Posted by MKB

The JCM800 model 2205 and 2210 both have diode clipping, as well as the 3203 Artist 30W. Also the model 2555 and 2550 heads (basically a Jubilee) have diode clipping. These are just heads, the corresponding combo amps have the diode clipping too.

For some reason Marshall went nuts with diode clipping as soon as they started embracing channel switching. Marshall seemed to have a desire to never put more than 3 tubes in a preamp for much of the eighties and nineties. They use the LED method in a few amps and pedals (Jubilee and Guv'nor respectively), but are also quite fond of using bridge rectifiers with the + and - pins connected with a diode. This basically gives you the effect of three rectifier diodes in series, for a 2.1V clipping level. The 2205 and 2210 heads use the bridge rectifier method.

Many of the recent Marshall tube amps do not have diode clipping however.

Actually the first version of the 2205/4210 Combo had 4 diodes in the end of the preamp and the master after the PI. The circuit was changed sometime in 1984 i believe.

coldsteal2 · 01-14-2009, 06:12 PM

Quote:

Originally Posted by travismbrown

I have a 900 and ive heard people complain about diode clipping, but to be honest i dont know what the hell it really is. . .

its pretty much puttying an Overdrive in your
preamp.

If you dont like the cliping all you have to do is
use the clean channel and crank it

really its no big deal
I see people gripe about having Cliping in thier preamp
but then will buy a vintage straight amp, but then put an OCD or DS1
in front of it...........????? you know. whats the difference, you just added clipping

I get a kick out of people that gripe about having to have a Hand Wired PTP old plexi, and
original cloth wireing, pots and bubblebee caps in thier les pauls
then string a long line of modern solid state stomp boxes in front of the
amp............................

comon guys...., so what if there is cliping in an OD chanel

***Adwex*** · 01-14-2009, 06:40 PM

Quote:

Originally Posted by coldsteal2

its pretty much puttying an Overdrive in your
preamp.

If you dont like the cliping all you have to do is
use the clean channel and crank it

really its no big deal
I see people gripe about having Cliping in thier preamp
but then will buy a vintage straight amp, but then put an OCD or DS1
in front of it...........????? you know. whats the difference, you just added clipping

I get a kick out of people that gripe about having to have a Hand Wired PTP old plexi, and
original cloth wireing, pots and bubblebee caps in thier les pauls
then string a long line of modern solid state stomp boxes in front of the
amp............................

comon guys...., so what if there is cliping in an OD chanel

Well said, coldsteal. I've owned 2 Marshall "heads" in my life, a JCM 900 that I sold recently, and a 2555 Jubilee, my main amp currently. Both have diode clipping.

The JCM 900 sounded terrible (IMHO).

The Jubilee sounds awesome.

Was it the diodes that made the 900 bad? I don't know.
Is it the diodes that makes the Jubilee great? I don't know.

coldsteal2 · 01-14-2009, 07:00 PM

Nah its the bad EQ in the 900 that makes people not like
it i think, something easily fixed with an eq in the loop.

Jubilleee does sound awesome.

My bad, i noticed that a few months earlier i said almost the same
thing hahah

nakleh · 01-14-2009, 07:10 PM

All this 900 talk is making me reconsider selling my JCM 900 4100. I was planning on selling it after buying my 1978 JMP 2204 but there is something about it I still like.. with the right tubes and biased properly, it fucking growls..

maybe I'll hold onto it for a while and see how I feel later on.

steelhorse · 01-15-2009, 07:11 AM

Quote:

Originally Posted by Adwex

Well said, coldsteal. I've owned 2 Marshall "heads" in my life, a JCM 900 that I sold recently, and a 2555 Jubilee, my main amp currently. Both have diode clipping.

The JCM 900 sounded terrible (IMHO).

The Jubilee sounds awesome.

Was it the diodes that made the 900 bad? I don't know.
Is it the diodes that makes the Jubilee great? I don't know.

Well said Adwex......

I think.

***Adwex*** · 01-15-2009, 10:31 AM

Quote:

Originally Posted by coldsteal2

Nah its the bad EQ in the 900 that makes people not like
it i think, something easily fixed with an eq in the loop.

...

Yeah, without an eq in the loop, I couldn't even use the thing. By itself it had NO low end at all.

Shawn Fate · 01-15-2009, 11:41 AM

Marshalls are not really known for huge bass.
If you want a JCM 800 with huge low end , buy a RedBear amp, its pretty much a JCM 800 with enough bass to scare off dual rectifiers.

***Adwex*** · 01-15-2009, 11:43 AM

Quote:

Originally Posted by Shawn Fate

Marshalls are not really known for huge bass.
If you want a JCM 800 with huge low end ........<snip>

Don't need it, got a Jubilee

I've been told to turn the bass down.

marshallhonk · 01-15-2009, 11:59 AM

I have to tell you I'm surprised... I consider the JCM 900 4100 to be the holy grail. I'm on my 3rd one... I keep selling them for "nicer amps".. ie several mesa stiletto's, roadster, 2ch recto, the kerry king 800, a silver jubilee combo,... I keep coming back to the 900's I LOVE the distortion, I alway do a full re-tube with JJ E34L's and ECC83's. I get mass gain and mass bass. I just picked up a 4102 that I am converting into a separate head and cab, white stained pine... it looks sweet.

For me the holy grail is a 100watt dual reverb and a 1960A. can't be beat!!!

10-15-2008, 02:24 AM	#61 (permalink)
steelhorse Senior Member Join Date: May 2008 Posts: 3,888	Re: What The Hell Is Diode Clipping???? I didn't realize KISS was so disrespected. __________________ www.ricojronline.com 760-956-6619 Garmopat Pedal Mods "I wouldn't mind hearing your head smash through a glass door. That would be cool..." luekmeyer

10-15-2008, 02:49 AM	#63 (permalink)
coldsteal2 Senior Member Join Date: Sep 2007 Location: Chico, CA Posts: 1,555	Re: What The Hell Is Diode Clipping???? dont get me wrong, i love reissue guitars with vintage pickups, capacitors and pots, and ptp vintage amps. __________________ http://www.youtube.com/user/kroftkarl http://www.soundclick.com/bands/defa...&content=music

10-15-2008, 05:02 AM	#64 (permalink)
5er driver Senior Member Join Date: Dec 2007 Location: Stuttgart, Germany Posts: 182	Re: What The Hell Is Diode Clipping???? Me too, but this is a killer line: "then put 25 transistor stomp boxes in between their guitar and their vintage amp then whine about a diode in a 900..... " __________________ The 5er Driver Now Annoying In ((((((Stereo)))))) Plug that beotch in an' let her rip!

10-15-2008, 08:41 AM	#65 (permalink)
codyfarmer Senior Member Join Date: May 2008 Posts: 110	Re: What The Hell Is Diode Clipping???? This is a very good thread +1 __________________ I play guitar and wakeboard alot...actually, wakeboarding is my job, guitar is my hobby. Current gear: Marshall JCM2000 DSL50 Marshall Silver Jubilee 2555 '79 Fender Twin Reverb Marshall 1960BX cab Gibson Les Paul Standard (probably the heaviest one ever, 10.6lbs) Fender American Stratocaster Martin DM

10-15-2008, 09:04 AM	#66 (permalink)
DragonSarc Senior Member Join Date: Jun 2008 Location: San Leandro, CA Posts: 495	Re: What The Hell Is Diode Clipping???? ^----------- + 1 I miss my 900 shouldnt have sold it

10-15-2008, 10:31 AM	#67 (permalink)
travismbrown Member Join Date: Aug 2008 Posts: 44	Re: What The Hell Is Diode Clipping???? How easy would it be to remove diode clipping from my 900 dual verb 100 watter? How dramatically would that change its tone?

10-15-2008, 10:56 AM	#69 (permalink)
stock_hippie Senior Member Join Date: Mar 2008 Posts: 626	Re: What The Hell Is Diode Clipping???? gotto get a SL-X!!!

10-16-2008, 10:24 PM	#72 (permalink)
HOT TUBES 70 Senior Member Join Date: Oct 2008 Location: SASKATOON Posts: 1,675	Re: What The Hell Is Diode Clipping???? speaking of killer sounding marshalls has anyone played the kerry king amp?

10-16-2008, 11:25 PM	#73 (permalink)
stock_hippie Senior Member Join Date: Mar 2008 Posts: 626	Re: What The Hell Is Diode Clipping???? you take your diode to the shoppe...you have her take a seat... and look thru the book and pick a style...you say youll be back in an hour..when you return.pay and dont forget to say how good she looks.......lol

10-18-2008, 09:15 AM	#74 (permalink)
Shawn Fate Senior Member Join Date: Jul 2007 Posts: 458	Re: What The Hell Is Diode Clipping???? Amplifier overdrive and distortion is usually achieved by signal clipping,pushing the gain until the signal peaks are chopped off. "Real" tube overdrive isn't possible without major changes (adding additional preamp stages, etc.) Preamp clipping can be simulated by installing a diode-clipping circuit. More ballsy sound (especially at low volumes.) In theory, diodes conduct current in only one direction. But they don't operate "perfectly." All diodes have a "forward voltage" they won't conduct until that voltage is reached. If a diode is connected between the signal path and the ground, the signal won't be channeled (shunted) to ground until it exceeds the forward voltage. And even then, the whole signal isn't dissipated, only the portion of the signal above that forward voltage. So it's peaks are simply "chopped off." But it also results in more attenuation, as some of the signal is lost. That isn't all bad. Clipping the loudest parts is also a form of "limiting" you loose some dynamics, but accentuate the lower-volume sounds. Plus, many amps don't begin to distort until turned up too loud for many venues. Like a stomp-box, diode-clipping lends a killer sound at a lower volume. asymmetrical clipping, offers the most natural and "tube-like" sound. Plus, it's the most flexible--any number of diodes in series can be used to shape the effect. Germanium diodes tend to have softer transitions which give a non-linear, more "tubey" sound. But silicon diodes can give a sharper "square wave" metallic distortion, if that's your thing. MOSFET transistors and Zeners can also be employed to establish higher clipping thresholds. You can even use LEDs as clipping diodes. Marshall MGs use those. Many players call all 2203 style master volumes JCM-800's, but these 2203 amps were being made long before Marshall began calling their amps JCM-800's. Also, there were JCM-800's being made which used diode clipping, and thus were not the older style 2203 circuit. Early JCM-800's with diode clipping in----G1---EQ---gain---G2---DIODES---volume--G3--loop--Phase Inverter---master volume---> This complex circuit was Marshall's first attempt at mixing tube and transitor distortion in its larger amplifiers. The mix of tube gain and diode clipping produced more distortion, but some players thought the sound was too "buzzy" and "thin" and "cold" compared to Marshall's all tube designs. Later JCM-800's, and JCM-900's with diode clipping (diodes in rectifier circuit) in----G1---------volume----G2---DIODES----G3-------------------------EQ---master volume---> Marshall refined the concept in its late JCM-800's and JCM-900's. Using solid state diodes is a lot cheaper than adding new tube gain stages, and many of the new hard rock and metal players were beginning to appreciate the harder sound of these amps.

10-18-2008, 01:14 PM	#76 (permalink)
Shawn Fate Senior Member Join Date: Jul 2007 Posts: 458	Re: What The Hell Is Diode Clipping???? JCM 800 model 4210 and model 2205 both use diode clipping. Models 2210 and model 4211 have extra tube gain stage after the diode clipping. The diode clipping itself had been altered to a more complex arrangement-more like a diode bridge rectifier, and the EQ was repositioned to after the third gain stage. Much like the 2203 amps.

10-18-2008, 01:20 PM	#78 (permalink)
Shawn Fate Senior Member Join Date: Jul 2007 Posts: 458	Re: What The Hell Is Diode Clipping???? I forgot about the 3203..jubilee was already talked about so I did not bring it up.

10-18-2008, 01:47 PM	#79 (permalink)
PaoloJM Senior Member Join Date: Jun 2008 Location: Cork, Ireland Posts: 534	Re: What The Hell Is Diode Clipping???? Well that's my new thing learned for today!! __________________ www.youtube.com/paolojm

10-18-2008, 03:05 PM	#80 (permalink)
HOT TUBES 70 Senior Member Join Date: Oct 2008 Location: SASKATOON Posts: 1,675	Re: What The Hell Is Diode Clipping???? Shawn fate ..... great overview of diode clipping 101 , i mod various pedals on the side mostly just for fun , i have changed the clipping diodes in a few marshalls , and it makes a big difference , this is a simple mod that costs very little that gets great result . the break point of the 1n34a germainium makes it the warmest sounding diode ,but takes away a small amount of gian , but by adding 2 or 3 in series the gain reapears and sounds killer . i have also tried mixing all types of diodes for various sounds , the clipping path can be alterd also with small value caps across the diodes . these are just some of the tricks that amp mod guys use to make your marshall come alive . and again great info about clipping -SHAWN FATE

01-14-2009, 07:00 PM	#84 (permalink)
coldsteal2 Senior Member Join Date: Sep 2007 Location: Chico, CA Posts: 1,555	Re: What The Hell Is Diode Clipping???? Nah its the *bad EQ* in the 900 that makes people not like it i think, something easily fixed with an eq in the loop. Jubilleee does sound awesome. My bad, i noticed that a few months earlier i said almost the same thing hahah __________________ http://www.youtube.com/user/kroftkarl http://www.soundclick.com/bands/defa...&content=music

01-14-2009, 07:10 PM	#85 (permalink)
nakleh Member Join Date: Nov 2008 Location: Brooklyn, NY Posts: 69	Re: What The Hell Is Diode Clipping???? All this 900 talk is making me reconsider selling my JCM 900 4100. I was planning on selling it after buying my 1978 JMP 2204 but there is something about it I still like.. with the right tubes and biased properly, it fucking growls.. maybe I'll hold onto it for a while and see how I feel later on. __________________ nakleh Website • MySpace • Band MySpace 2006 Gibson Custom Shop Les Paul Custom 1978 Marshall JMP 2204 • 1993 Marshall JCM900 4100 • 1984 Marshall JCM800 4x12 Cab Egnater Rebel 20 Head • Avatar 1x12 Closed Back Cabinet Mac Pro Tower • Pod XT • Guitar Rig 3

01-15-2009, 11:41 AM	#88 (permalink)
Shawn Fate Senior Member Join Date: Jul 2007 Posts: 458	Re: What The Hell Is Diode Clipping???? Marshalls are not really known for huge bass. If you want a JCM 800 with huge low end , buy a RedBear amp, its pretty much a JCM 800 with enough bass to scare off dual rectifiers.

01-15-2009, 11:59 AM	#90 (permalink)
marshallhonk Junior Member Join Date: Jan 2009 Posts: 10	Re: What The Hell Is Diode Clipping???? I have to tell you I'm surprised... I consider the JCM 900 4100 to be the holy grail. I'm on my 3rd one... I keep selling them for "nicer amps".. ie several mesa stiletto's, roadster, 2ch recto, the kerry king 800, a silver jubilee combo,... I keep coming back to the 900's I LOVE the distortion, I alway do a full re-tube with JJ E34L's and ECC83's. I get mass gain and mass bass. I just picked up a 4102 that I am converting into a separate head and cab, white stained pine... it looks sweet. For me the holy grail is a 100watt dual reverb and a 1960A. can't be beat!!!

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