what would you do to get more bottom end chunk from your amp?

avivoni · 08-01-2012, 10:18 AM

looking for some of the experience of the members in this forum...what approach would you use?

now i know this is a broad topic since the bottom end chunk or the mudd on the other hand could be contributed from speakers, pickups, amp biased hot or cold ..but just give me the rundown from your experience

Stringjunkie · 08-01-2012, 10:53 AM

I would use my MXR 10 band eq for cut/boost if all of my other choices were made. You know cab /speakers, pups/guitar and amp eq'd to taste but I just wanted a bit more control. My 2 cents

avivoni · 08-01-2012, 11:12 AM

Quote:

I would use my MXR 10 band eq for cut/boost if all of my other choices were made

much appreciated

any other suggestions?

poeman33 · 08-01-2012, 11:33 AM

What amp and what speakers are you using? Huge difference with just those two things.

The Ozzk · 08-01-2012, 11:35 AM

I think of my 2203 as a "punch" beast. Even though you can get sweet power tube saturation and pre-amp gain, sometimes it's just not enough.

The 2203 is known to be one of those amps that can take pedals like no other. In my case I use a hot plate to get some of that power tube distortion in any situation (venue size). I keep the pre-amp at 6-7 and push the front end with my OD of choice. At the moment a Mesa boogie V-twin and an OFA modded OS-2.

Settings will change from venue to venue of course, but I think I have a consistent sound.

pedecamp · 08-01-2012, 11:53 AM

Boss GE-7 eq pedal. Running it flat but with the level up a notch is powerful. Also stacking another OD pedal such as a Bad Monkey as a clean boost behind the eq fattens it up even more.

plexifier · 08-01-2012, 12:13 PM

Add a resonance control if you're willing to mod the amp. You can even just add a fixed resistor and cap if you don't have a spare hole for a pot.

GIBSON67 · 08-01-2012, 12:49 PM

Add more speakers/cabs!

avivoni · 08-01-2012, 12:51 PM

Quote:

Originally Posted by pedecamp

Boss GE-7 eq pedal. Running it flat but with the level up a notch is powerful. Also stacking another OD pedal such as a Bad Monkey as a clean boost behind the eq fattens it up even more.

the bad monkey sounds nice

Quote:

What amp and what speakers are you using? Huge difference with just those two things.

a new jcm 800 one channel amp...it's got the thump and the chunk but i want more of it

Ken · 08-01-2012, 12:52 PM

Tune down to D or C. Yeah, I know that's not what you asked...!

Ken

The Ozzk · 08-01-2012, 01:50 PM

Quote:

Originally Posted by Ken

Tune down to D or C. Yeah, I know that's not what you asked...!

Ken

So very true

Wycked Lester · 08-01-2012, 02:19 PM

crank that bitch up.... If you need any more bass than that, get a bass player.....thats what they are for.

Wycked Lester · 08-01-2012, 02:20 PM

what are you using for speakers??

avivoni · 08-01-2012, 02:38 PM

Quote:

Originally Posted by Wycked Lester

what are you using for speakers??

jcm 800 4*12 with celestion g12-65...now with my 82 2204 there is plenty of bottom end so i think it's not the cab but something going on with the amp.It's bias at 36 with a plate voltage of 470..(it's a 50 watt amp)
So how about bias techies??
what would contribute to a better bottom end bias wise?? the hot bias or a colder bias??

plexifier · 08-01-2012, 02:56 PM

Quote:

Originally Posted by avivoni

...what would contribute to a better bottom end bias wise?? the hot bias or a colder bias??

Bias setting is not a tone control!

However, if you push the power section hard (loud), a slightly colder bias may give you a tighter bass response since the power tubes will run cleaner. It depends on the tubes, particular amp, etc.

EQ pedals have been mentioned but I don't think that's a good choice if you really want more bass. Boosting bass before the amp can cause too much overdrive in the lows and make things muddy without really adding much "bottom end chunk". They can work well in an effects loop though.

Les Moore · 08-02-2012, 02:52 AM

I just had a thread up where I adressed the "farting out" problem of my JMP´s. With the advice from our gurus here I ended up trying out different values on the cathode cap on V1a. Stopped at 1uF. Tightened up the bass in a fantastic manner.
Don´t know if this is what you´re after and/or the value of the same cap in your amp is as exagerated as the 1959/1987 circuits are (250 and 330 uF if I remember correctly).
Just trying to help

Wilder Amplification · 08-02-2012, 03:29 AM

If you want clean/tight punch, use a resonance cap in series with the negative feedback loop.

I typically use a 100K resistor with a 0.01uF cap in series, then tap the NFB from the 16 ohm tap. A 50K resistor in line with a 0.02uF cap with the NFB tapped off of the 4 ohm tap gives the same result.

For bias setting, colder settings keep the power section clean/tight. 60-65% is where I recommend it.

Nudge68 · 08-02-2012, 04:05 AM

Quote:

Originally Posted by Wilder Amplification

For bias setting, colder settings keep the power section clean/tight. 60-65% is where I recommend it.

I've always set mine to 70% for no other reason than I was told to do it like that sooooo long ago. Would this accentuate bottom-end "spongey mush" on some of my units? Next time I pull the chassis out I'll try 60-65%!

Due to this "spongey mush", I've compensated by using clean boosts into ODs. The boost giving the bump of course. The OD isn't set for grit, I just sweep the level and tone knobs between "zero" and "1/3" up (like 8am and 11am clock face) until I get the best thunk I can.

I did the same thing with the Boss EQ when I used one. I guess this does pretty much the same thing.

cheers,

Matt.

Wilder Amplification · 08-02-2012, 04:31 AM

Quote:

Originally Posted by Nudge68

I've always set mine to 70% for no other reason than I was told to do it like that sooooo long ago. Would this accentuate bottom-end "spongey mush" on some of my units? Next time I pull the chassis out I'll try 60-65%!

Due to this "spongey mush", I've compensated by using clean boosts into ODs. The boost giving the bump of course. The OD isn't set for grit, I just sweep the level and tone knobs between "zero" and "1/3" up (like 8am and 11am clock face) until I get the best thunk I can.

I did the same thing with the Boss EQ when I used one. I guess this does pretty much the same thing.

cheers,

Matt.

70% is not a "must be set to this" kind of spec. It is a "maximum do not exceed me" spec.

You can go colder than that all day long. Rules of biasing are -

1) Do not bias the amp so hot that your valves overheat (noticeable by the plates turning red)

2) Do not bias the amp so cold that it sounds bad

Any setting between these two points that yields great tone is fair game.

The hotter you bias the amp, the less headroom the power amp has, which causes you to run into "grid limiting" at lower signal levels, hence the more "mush" you get. If you're going for a punchy "high gain" type sound, overdriving the power section is counter-productive to this. Overdriven power amps are more of a looser/classic sound. It's a completely different world.

Also, due to variations in wall voltage, which cause HUGE changes in B+ voltage (3:1 change ratio...a 1V change in mains voltage yields a 3V change in B+ voltage on 120V mains), you should NEVER bias on the ragged edge of 70%.

To further tighten things up, shelving lows at the front end is a necessity to prevent low end distortion. If you have an effects loop, you can use an EQ pedal to add clean bass later in the signal chain after the distorting circuitry.

Nudge68 · 08-02-2012, 05:01 AM

Quote:

Originally Posted by Wilder Amplification

70% is not a "must be set to this" kind of spec. It is a "maximum do not exceed me" spec.

You can go colder than that all day long. Rules of biasing are -

1) Do not bias the amp so hot that your valves overheat (noticeable by the plates turning red)

2) Do not bias the amp so cold that it sounds bad

Any setting between these two points that yields great tone is fair game.

The hotter you bias the amp, the less headroom the power amp has, which causes you to run into "grid limiting" at lower signal levels, hence the more "mush" you get. If you're going for a punchy "high gain" type sound, overdriving the power section is counter-productive to this. Overdriven power amps are more of a looser/classic sound. It's a completely different world.

Also, due to variations in wall voltage, which cause HUGE changes in B+ voltage (3:1 change ratio...a 1V change in mains voltage yields a 3V change in B+ voltage on 120V mains), you should NEVER bias on the ragged edge of 70%.

To further tighten things up, shelving lows at the front end is a necessity to prevent low end distortion. If you have an effects loop, you can use an EQ pedal to add clean bass later in the signal chain after the distorting circuitry.

Actually, what you say here re hot vs cold is the same as what the guy told me who restored my '66 Vox recently. I had no clue what he was talking about. Now that you've written this and I've re-read a few times, makes perfect sense.

Mate, the crap you think you correctly "learn" when you're a kid is near impossible to "unlearn" as an adult. Better late than never!

Thank you very much

cheers,

Matt.

blues_n_cues · 08-02-2012, 05:50 AM

take the casters off.

avivoni · 08-02-2012, 10:07 AM

Quote:

Originally Posted by blues_n_cues

take the casters off.

Quote:

cathode cap on V1a. Stopped at 1uF. Tightened up the bass in a fantastic manner.

i am taking it to a tech next weel to do a filter cap job...he's a friend so we might give that a shot
thanks

Quote:

70% is not a "must be set to this" kind of spec. It is a "maximum do not exceed me" spec.

You can go colder than that all day long. Rules of biasing are -

1) Do not bias the amp so hot that your valves overheat (noticeable by the plates turning red)

2) Do not bias the amp so cold that it sounds bad

Any setting between these two points that yields great tone is fair game.

The hotter you bias the amp, the less headroom the power amp has, which causes you to run into "grid limiting" at lower signal levels, hence the more "mush" you get. If you're going for a punchy "high gain" type sound, overdriving the power section is counter-productive to this. Overdriven power amps are more of a looser/classic sound. It's a completely different world.

Also, due to variations in wall voltage, which cause HUGE changes in B+ voltage (3:1 change ratio...a 1V change in mains voltage yields a 3V change in B+ voltage on 120V mains), you should NEVER bias on the ragged edge of 70%.

thanks wilder ..we will also experiment with different bias settings

CAPDUNN · 08-04-2012, 07:56 PM

Use a 6100..............

DPTONE5 · 08-04-2012, 10:06 PM

I am a big Greenback fan, but now that I am using two cabinets, one with Greenbacks and the other with very worn in G12T-75's, I am getting a really nice low end, tight thump. I really like how the G12T-75's sound when palm muting!!

DP

dreyn77 · 08-05-2012, 07:45 AM

try tightening all the nuts, bolts and screws! in your head. NOT you ffrankenstein! I just got the 'Chunk' from Megadeth's endgame JVM - with a non JVM amp! (non 1959rr) and a Warlock guitar (no active pickups, just stock bc riches)! try a FLOYD ROSE equiped guitar - the springs interact with the strings which give you a different 'chunk' from your amp. the hard-tail bridge on a Les Paul won't do it!

08-01-2012, 10:18 AM	#1 (permalink)
avivoni Senior Member Join Date: Dec 2010 Posts: 1,317	what would you do to get more bottom end chunk from your amp? looking for some of the experience of the members in this forum...what approach would you use? now i know this is a broad topic since the bottom end chunk or the mudd on the other hand could be contributed from speakers, pickups, amp biased hot or cold ..but just give me the rundown from your experience __________________ The JCM800 series jcm 800 4104 82 jcm 800 2204 81 jcm 800 1987 NMV 83

08-01-2012, 10:53 AM	#2 (permalink)
Stringjunkie Senior Member Join Date: Nov 2010 Location: S W Florida Posts: 3,311	Re: what would you do to get more bottom end chunk from your amp? I would use my MXR 10 band eq for cut/boost if all of my other choices were made. You know cab /speakers, pups/guitar and amp eq'd to taste but I just wanted a bit more control. My 2 cents __________________ Orange Dark Terror JCM1H DSL1H Sourmash 1x12/reaper Sourmash 1x12/green beret Fender American standard strat-stock Fender Blacktop strat-MHD pups Ibanez RG- MHD pups Gibson LP 50s tribute studio-stock

08-01-2012, 11:33 AM	#4 (permalink)
poeman33 Senior Member Join Date: May 2008 Location: Ontario, Canada Posts: 4,465	Re: what would you do to get more bottom end chunk from your amp? What amp and what speakers are you using? Huge difference with just those two things. __________________ --------------- CSA (Certified Strat Addict)

08-01-2012, 11:35 AM	#5 (permalink)
The Ozzk Senior Member Join Date: Mar 2011 Location: Calgary, AB Posts: 1,222	Re: what would you do to get more bottom end chunk from your amp? I think of my 2203 as a "punch" beast. Even though you can get sweet power tube saturation and pre-amp gain, sometimes it's just not enough. The 2203 is known to be one of those amps that can take pedals like no other. In my case I use a hot plate to get some of that power tube distortion in any situation (venue size). I keep the pre-amp at 6-7 and push the front end with my OD of choice. At the moment a Mesa boogie V-twin and an OFA modded OS-2. Settings will change from venue to venue of course, but I think I have a consistent sound. avivoni likes this. __________________ Amps: 82' JCM 800 2203 09' JCM 800 KK 11' VM2466 11' C5H Cabs: JCM800B 4x12 1960A 4x12 x 2 1960B 4x12 C110 Guitars: 91' Orville Les Paul Custom 11' Explorer Melody Maker 11' Epiphone LP Standard

08-01-2012, 11:53 AM	#6 (permalink)
pedecamp Senior Member Join Date: Dec 2009 Posts: 2,399	Re: what would you do to get more bottom end chunk from your amp? Boss GE-7 eq pedal. Running it flat but with the level up a notch is powerful. Also stacking another OD pedal such as a Bad Monkey as a clean boost behind the eq fattens it up even more. DPTONE5 likes this. __________________ DSL50

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08-01-2012, 12:13 PM	#7 (permalink)
plexifier Senior Member Join Date: Aug 2011 Posts: 474	Re: what would you do to get more bottom end chunk from your amp? Add a resonance control if you're willing to mod the amp. You can even just add a fixed resistor and cap if you don't have a spare hole for a pot. avivoni likes this.

08-01-2012, 12:49 PM	#8 (permalink)
GIBSON67 Senior Member Join Date: Sep 2008 Location: Lakeland, TN Posts: 3,298	Re: what would you do to get more bottom end chunk from your amp? Add more speakers/cabs! avivoni likes this.

08-01-2012, 12:52 PM	#10 (permalink)
Ken Senior Member Join Date: Feb 2009 Location: Arlington Heights, IL Posts: 6,246	Re: what would you do to get more bottom end chunk from your amp? Tune down to D or C. Yeah, I know that's not what you asked...! Ken blues_n_cues, The Ozzk and bvoris like this. __________________ 1999 Marshall DSL 50 Music Man 65 Reverb late 1970's (?) Late 1970's (?) Fender Champ Marshall battery amp 1980 Model 1982A 4x12 cabinet G12H-80's 444 cones 1983 Model 1982B 4x12 cabinet G12-80's 444 cones PRO 4x12 from the 1970's Woodson 2x12 1976 Les Paul Standard Epiphone Les Paul knockoff ESP Lawsuit Explorer 1979 Chiquita Travel Guitar 1995 Taylor 310

08-02-2012, 02:52 AM	#16 (permalink)
Les Moore Senior Member Join Date: Mar 2011 Location: Stockholm Sweden Posts: 1,745	Re: what would you do to get more bottom end chunk from your amp? I just had a thread up where I adressed the "farting out" problem of my JMP´s. With the advice from our gurus here I ended up trying out different values on the cathode cap on V1a. Stopped at 1uF. Tightened up the bass in a fantastic manner. Don´t know if this is what you´re after and/or the value of the same cap in your amp is as exagerated as the 1959/1987 circuits are (250 and 330 uF if I remember correctly). Just trying to help __________________ Les Paul, Fender Highway One, Franken-Lead, homemade Stratocaster, Boss TU2, Fame pedalpower, Ibanez Tube Screamer, Korg Wah, Budwah, Voodoolab ampselector, Weber attenuator, Whirlwind A/BY, POG2, Holy Grail nano, JMP 50W `72, Super Lead 100W `69, Ceriatone JTM45, 412 cab, Twin Reverb http://www.gjutjarn.com Assumption is the mother of all ****ups. Anonym. He got up and smiled as he did a crouchingtiger, hidden drunkass moonwalk backwards into my wall. BillyBlades

08-02-2012, 03:29 AM	#17 (permalink)
Wilder Amplification Senior Member Join Date: Oct 2009 Location: Fresno, CA Posts: 6,165	Re: what would you do to get more bottom end chunk from your amp? If you want clean/tight punch, use a resonance cap in series with the negative feedback loop. I typically use a 100K resistor with a 0.01uF cap in series, then tap the NFB from the 16 ohm tap. A 50K resistor in line with a 0.02uF cap with the NFB tapped off of the 4 ohm tap gives the same result. For bias setting, colder settings keep the power section clean/tight. 60-65% is where I recommend it. avivoni likes this. __________________ Jon Wilder Wilder Amplification - The official home of the 80s cock of the walk "Schwank" http://www.wilderamps.com http://www.facebook.com/wilderamps

08-02-2012, 05:50 AM	#21 (permalink)
blues_n_cues Senior Member Join Date: Jul 2010 Location: north of nashville Posts: 8,524	Re: what would you do to get more bottom end chunk from your amp? take the casters off. __________________ LIFE,LIBERTY,& the pursuit of TONE. 2007 Epi LP custom ltd. in ivory 2010 Austin gold top w/ P90s modded Squier strat >Zoom G1(tuner)vox 847 wah >boss sd-1 > vintage mxr dist+ > alesis midiverbs 2(delay)& 3(verb & or chorus) > jcm800 2204 > 4x12 w/ altec lansing 417-8H spkrs my music- https://soundcloud.com/rlc-ltd

08-04-2012, 07:56 PM	#23 (permalink)
CAPDUNN Senior Member Join Date: Sep 2010 Location: San Diego Posts: 1,650	Re: what would you do to get more bottom end chunk from your amp? Use a 6100.............. __________________ Marshall 6100LM with EL34s and the LM mod removed powering 1960A and B cabinets loaded with a mix of Vintage 30s and G12T75 speakers. Marshall 6101 with EL34s and a Vintage 30. 1912 loaded with a PreRola Greenback. I can't kill this speaker!

08-04-2012, 10:06 PM	#24 (permalink)
DPTONE5 Senior Member Join Date: Jan 2010 Location: Pennsylvania Posts: 1,953	Re: what would you do to get more bottom end chunk from your amp? I am a big Greenback fan, but now that I am using two cabinets, one with Greenbacks and the other with very worn in G12T-75's, I am getting a really nice low end, tight thump. I really like how the G12T-75's sound when palm muting!! DP __________________ Marshall Amps - 1987XL, JMP 2204, JCM 800 2203X, 2555 Jubilee, JCM 800 2210, 6100 Cabinets - 1960BX, 1960B JCM 900 Guitars - PRS CU 24, 91' Gibson LP Classic, Fender Clapton Strat, Jackson SL-1, Taylor 410-CE, Fender Highway One P Bass Pedal Board - Boss Tuner, Fulltone Fulldrive II Mosfet, ReIssue Ibanez TS-808, Ernie Ball Volume Pedal to amp in. Loop - Boss Chorus, MXR Carbon Copy, Lee Jackson Mr. Springgy, Boss GE-7 EQ (Monte Allums Mod)

08-05-2012, 07:45 AM	#25 (permalink)
dreyn77 Banned Join Date: Feb 2012 Posts: 996	Re: what would you do to get more bottom end chunk from your amp? try tightening all the nuts, bolts and screws! in your head. NOT you ffrankenstein! I just got the 'Chunk' from Megadeth's endgame JVM - with a non JVM amp! (non 1959rr) and a Warlock guitar (no active pickups, just stock bc riches)! try a FLOYD ROSE equiped guitar - the springs interact with the strings which give you a different 'chunk' from your amp. the hard-tail bridge on a Les Paul won't do it!

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