taming a Marsh bassman

Is there any way of getting the Marsh bassman head to break up at a lower volume. im runnin a gretsch hotrod thru a nocturne and maxon ad999 and then into a marsh bassman head and vibrolux cab - its a great sound but way too loud. Ive relaced the stock power tube with a nos jan phillips and ive replaced the preamp tubes with ruby 12ax7's. Does it need re-biasing? Im trying to find a solution rather than using a hotplate attenuator cos im not keen on them and I would rather get the amp to break up earlier without one.

Well, you could push it harder with the nocturne.

how comes your not keen on a hotplate???
just wondering as am currently saving for one to get my marsh to distort without pulling all the things of the shelves

I use to run a THD Hotplate 4ohm REd. So useful in the studio (one track called
saturate was with one bassman fully dimed with the THD on pushing about 5watts.
the other bassman was just ballz loud all the way up.)
quite versatile too in smaller venes.. Let me turn the entire amp all the way up
at 1 watt.

Ronnie Crutcher from the Hillbilly Casino uses an attenuator as well
on his Marsh bassman. The Dr Z airbrake.

I think its totally worth the expense because it instantly puts a vintage marshall into your hands at controllable levels.

This one is suppose to be the best on the market right now:
http://www.ultimateattenuator.com/

Chunkeymac - For me the thd hotplate loses my tone, especially when you switch to -8db and beyond. I dont mind when im playin at home but when im giggin I think it sounds harsh and cold but then again it could be that im perceiving it this way cos I cant feel the air wafting around the speaker and I just need to get used to it. What I would say is to do your best to try one for yourself cos most people DO love em but im not alone in my opinion that something is lost when its engaged.

There are other attenuaters on the market that use different technology to do the same job so do a bit of research first cos those THD's are not cheap.
Check this out:
http://www.tedweber.com/atten.htm

booty wrote:

Chunkeymac - For me the thd hotplate loses my tone, especially when you switch to -8db and beyond. I dont mind when im playin at home but when im giggin I think it sounds harsh and cold but then again it could be that im perceiving it this way cos I cant feel the air wafting around the speaker and I just need to get used to it. What I would say is to do your best to try one for yourself cos most people DO love em but im not alone in my opinion that something is lost when its engaged.

There are other attenuaters on the market that use different technology to do the same job so do a bit of research first cos those THD's are not cheap.
Check this out:
http://www.tedweber.com/atten.htm

spot on right! thats why I dont have one anymore hahah! They all feel real squishy but they do
let you get crazy at low vol

greetings tavo
What settings do you have on your bassman and nocturne if you're playin a small venue and you need the volume down but you wanna retain gritchiness?

booty wrote:

greetings tavo
What settings do you have on your bassman and nocturne if you're playin a small venue and you need the volume down but you wanna retain gritchiness?

Number one mistake is playing though an open back cab with a bassman and expecting to not
piss off the soundman and make the front row leave.
You must play through a closeback cab and there is absolutely no reason to comply with a soundman trying to put your amp/cab way back by the drummer (aka backline).
Put the amp at a 45 degree angle to you and the band. I guarantee you will hear your full tone/feel it and even the drummer will hear you over his snare all the while no mad patrons and jerk sound guy.

normal channel Volume 3, treble 7-8, bass 0-2, presence 7-9 // nocturne bass cut 7 oclock, gritch at 4 oclock.
If you still get crap from sound man or bandmates at this level.. plug into input 2 of the normal channel as this is a 10db cut, you will only then need to dime your presence control, bass to flavor.

again settings I mention above are worthless with an openback cab. The other thing I did for 3 1/2 yrs with the same sunday gig in a big cavernous glass and mahogany building was use a clear plexi gobo at a 45 degree angle for reflectivity back to the bassist and drummer but shielding the audience (thus the soundman) If it is placed forward enough for the mic and stand to clear you should be able to stand about 3 feet in front with a direct ear to the cab.

In this clip I've got a 28"x18" clear piece of shatter proof plexi in front of my cab at 45degrees.
This video is from 2 years ago playin gospel for a church service (I retired) and the dude filming is about 25yrs away, close enough to hear the front of house monitors and pickup my stage volume. It was always polite but clear and to my liking. They only ever complained about the damn drums and my guy was forced to play those roland rubbermaid things (he's hiding in the background)


https://www.youtube.com/watch?v=kPntrbktaZQ

cheers tavo
thanks for the info - i'll look into you suggestions - i never even considered the 2nd input on the marsh bassman so ill try it cos Id really prefer to leave the hotplate at home if possible.
whilst youre on tho, should I have had the marsh head re-biased since swapping all the valves ?
And dont worry, im not using an open backed cab. im using a fender 2x12 vibrolux closed back cab.
Nice tune by the way.

booty wrote:

cheers tavo
thanks for the info - i'll look into you suggestions - i never even considered the 2nd input on the marsh bassman so ill try it cos Id really prefer to leave the hotplate at home if possible.
whilst youre on tho, should I have had the marsh head re-biased since swapping all the valves ?
And dont worry, im not using an open backed cab. im using a fender 2x12 vibrolux closed back cab.
Nice tune by the way.

thanks Boo'

if you switched powertubes from a 6L6GC to the small bottle tungsol 5881, a
definite rebias is necessary as the 5881 valves are about 23watts each max.
(ps. 4ohm load on the cab I assume)

btw.. using input two does not make the amp break up soon but later..
The bass channel on the other hand has 2 gain stages and will break up much
sooner "IF" you remove the treble bleed capacitor. ( little one second clip out
jobby).. as that cap bleeds off highs to ground. Once that is removed the bass
channel is a full functioning version of the normal channel with twice the gain on
tap. Townsend all the way

cheers tavo
Yep, the vibrolux cab IS 4 ohms.
The power tubes I put in are USA made JAN Phillips 6L6WGB.Do I still need to re re-bias and if so, could you please tell me the details of how to re-bias the Marsh and also the details of how to do the bass channel mod, much, much appreciated.
BTW If Ive been running this rig WITHOUT the correct bias, what in actual fact has this meant regarding the amps performance?
Sorry if youre goin over ground that you must have covered umpteen times but its invaluable to us amateurs out here!
ta mate

p.s
whats the difference between the tungsol 5881 and the JAN Phillips 6l6wgb? which do you prefer?

booty wrote:

cheers tavo
Yep, the vibrolux cab IS 4 ohms.
The power tubes I put in are USA made JAN Phillips 6L6WGB.Do I still need to re re-bias and if so, could you please tell me the details of how to re-bias the Marsh and also the details of how to do the bass channel mod, much, much appreciated.
BTW If Ive been running this rig WITHOUT the correct bias, what in actual fact has this meant regarding the amps performance?
Sorry if youre goin over ground that you must have covered umpteen times but its invaluable to us amateurs out here!
ta mate

first off didnt that amp come stock with electroharmonix "Tungsol reissue 5881" power tubes?

Technically the NOS JAN Phillips 6L6WGBs are suppose to be essentially the same build as original tungsol 5881 power tubes but sources say these soviet reissues
are actually much less hardy and barely hit the 23watts a tube mark. Others say the
JJ 6V6's are actually small bottle 6L6's and much more like Tungsol 5881s..

you swappin your reissue 5881s for NOS 6L6WGBs means you should be able
to bias slightly hotter. This shortens tube life but man what a sound!
All saying that if you bias outside of spec hot or cold you shorten the life of the tube. I run hotter so my Phillips start losing strength within a year and a half, my preamp tubes are pummel'd by the preamp and start going microphonic with 8 months. who cares there's only one preamp tube and phase inverter tune on the normal channel. when my ruby's start poopin I swap em for the bass channels 2 ruby pre's.

restoring your bassman's bass channel to a good guitar rock channel
Remove the .002uF capacitor in parallel with the 100K resistor right before the phase inverter section.
The .002uF drains your highs to ground.

cheers tavo
Ive sourced a guitar/amp tech thru my local music shop so im gonna get him on the case. I'll pass on what you told me he will need to do in order to convert the bass channel, but regarding the re-biasing,- do I need to give him any more instructions or do I just tell him to run it a little hotter?
as ever, ta mate for your help with this.

booty wrote:

cheers tavo
Ive sourced a guitar/amp tech thru my local music shop so im gonna get him on the case. I'll pass on what you told me he will need to do in order to convert the bass channel, but regarding the re-biasing,- do I need to give him any more instructions or do I just tell him to run it a little hotter?
as ever, ta mate for your help with this.

The tech will want to spec the power tubes within range and will advise you to
not push it. This is for your own good and your wallet, but if you like to live dangerously you tell em you like your air/fuel ratio on your 4 barrel RICH!

ps. straight clipping out that diode is gonna mean a WHOLE lot more treble on
that bass channel but just attenuate as needed. I sure like my bass channel better
with strats n tele with this mod. Strangely when we did this to the Gomez el sonido
amps, the treble blast was like demon.. not so when done on the originals.
all to say if its tooo bright you can always pop a smaller value cap back on there
if needed. But only a girl would do that

ta
Thats what I needed to know. Next week im gonna get the amp sorted so watch this space and ill let you know how its gettin on.
cya soon

tvthewiredturtle wrote:

booty wrote:

cheers tavo
Yep, the vibrolux cab IS 4 ohms.
The power tubes I put in are USA made JAN Phillips 6L6WGB.Do I still need to re re-bias and if so, could you please tell me the details of how to re-bias the Marsh and also the details of how to do the bass channel mod, much, much appreciated.
BTW If Ive been running this rig WITHOUT the correct bias, what in actual fact has this meant regarding the amps performance?
Sorry if youre goin over ground that you must have covered umpteen times but its invaluable to us amateurs out here!
ta mate

first off didnt that amp come stock with electroharmonix "Tungsol reissue 5881" power tubes?

Technically the NOS JAN Phillips 6L6WGBs are suppose to be essentially the same build as original tungsol 5881 power tubes but sources say these soviet reissues
are actually much less hardy and barely hit the 23watts a tube mark. Others say the
JJ 6V6's are actually small bottle 6L6's and much more like Tungsol 5881s..

you swappin your reissue 5881s for NOS 6L6WGBs means you should be able
to bias slightly hotter. This shortens tube life but man what a sound!
All saying that if you bias outside of spec hot or cold you shorten the life of the tube. I run hotter so my Phillips start losing strength within a year and a half, my preamp tubes are pummel'd by the preamp and start going microphonic with 8 months. who cares there's only one preamp tube and phase inverter tune on the normal channel. when my ruby's start poopin I swap em for the bass channels 2 ruby pre's.

restoring your bassman's bass channel to a good guitar rock channel
Remove the .002uF capacitor in parallel with the 100K resistor right before the phase inverter section.
The .002uF drains your highs to ground.

This is one of the best posts about power tubes for a 6G6-B and this thread as a whole has a great deal of info!

TV, what types of tubes are going into the Blondeshell? Is it what you find best or is it user choice?

I'm certainly no authority on fender amps but what I have read/studied about
is that Leo Fender was a tinker, he wasnt a guitar player and he was always buying
large stocks of supply that were totally affordable quality.
I think the spec'd Tungsol 5881 was just a readily avail tube at the time and it
was reliable. They used these particular tubes in B-52 bombers in the servo motors.

Happy accidents were always occuring with Fender and in the case of these bassman
amps that worked out better for guitars, the circuits kind of designed around them.
Unique that these small bottle 6L6's break up fairly easy in the upper tone spectrum but stay tight in the low end. The fact that they stay tight in the low mids makes for a perfect design in my book for big hollowbody guitars with buckers.

Unfortunately tubes in general are expensive and keep going up in price, worse the
Tungsol NOS 5881 are beyond 5x the price of your standard russian tube. We have
electroharmonix making the reissue 5881 but is merely a shadow of what a good set of NOS are.
A perfect compromise is the NOS JAN Phillips 6L6WGB but it too runs near $85 a duet

so... while I use the NOS 5881 in one of my original blondes and the phillips in the other.. I am left having to build my Blondeshell 63 around the Reissue
5881 for availability, price point. What I DID do though is include bias test points and external bias pot so you can use whatever 6L6 type tube suits your fancy.
According to JJ spec on their 6V6, they can be used in this amp as well since they spec at a higher plate voltage than even the tungsol reissue 5881.. This gives you
a nice palette to choose from.

that's interesting about the JJ 6V6's. A good option for tubes for a 6G6-B as well

Is EH the only one reissuing 5881's? I thought I heard that TAD has some small bottle 6L6's or 5881's that were decent?

Where is a decent place to get NOS 6L6WGB's and 5881's?

Also, in your opinion what would be a good tube set up for more marshall flavor out of a 6G6-B...or do speakers play more a roll in that? I'd imagine a good KT66 wouldn't hurt either.

tvthewiredturtle wrote:

I'm Incinerator wrote:

that's interesting about the JJ 6V6's. A good option for tubes for a 6G6-B as well

Is EH the only one reissuing 5881's? I thought I heard that TAD has some small bottle 6L6's or 5881's that were decent?

EH has the name for the small bottle 5881

the tad tube is a small bottle 6L6GC, its not bad but less distinct in tight lows

Where is a decent place to get NOS 6L6WGB's and 5881's?
Dougs tubes
Also, in your opinion what would be a good tube set up for more marshall flavor out of a 6G6-B...or do speakers play more a roll in that? I'd imagine a good KT66 wouldn't hurt either.
The tubes I'm talkin about get the amp to clip much sooner, any big bottles are gonna milk full power from the amp's 50watt prowess

I forgot that a set of 5881's or 6L6WGB's are putting out less wattage than a set of 6L6GC's or KT66's would. How much do you think a set of JJ 6V6's put out? The JJ power tubes are pretty stout! I have a set of the EL84's in my CR and they make the CR a punchy rock machine.

I should have guessed dougs tubes, I guess I've never veered away from the EL84, 12AX7, and GZ34's.

I'm Incinerator wrote:

tvthewiredturtle wrote:

I'm Incinerator wrote:

that's interesting about the JJ 6V6's. A good option for tubes for a 6G6-B as well

Is EH the only one reissuing 5881's? I thought I heard that TAD has some small bottle 6L6's or 5881's that were decent?

EH has the name for the small bottle 5881

the tad tube is a small bottle 6L6GC, its not bad but less distinct in tight lows

Where is a decent place to get NOS 6L6WGB's and 5881's?
Dougs tubes
Also, in your opinion what would be a good tube set up for more marshall flavor out of a 6G6-B...or do speakers play more a roll in that? I'd imagine a good KT66 wouldn't hurt either.
The tubes I'm talkin about get the amp to clip much sooner, any big bottles are gonna milk full power from the amp's 50watt prowess

I forgot that a set of 5881's or 6L6WGB's are putting out less wattage than a set of 6L6GC's or KT66's would. How much do you think a set of JJ 6V6's put out? The JJ power tubes are pretty stout! I have a set of the EL84's in my CR and they make the CR a punchy rock machine.

I should have guessed dougs tubes, I guess I've never veered away from the EL84, 12AX7, and GZ34's.

Dont know what to say about the JJ's, that was just a suggestion based on their specs and some Tube jockeys that comment on them. I've used them for
my princetons and in tophat super deluxes.

regarding doug's tubes.. I have to use them because my whole suppliers are no longer carrying them as the stock is drying up. They went from $40 a duo, to $80
just in the last few yrs and I know its gonna just get worse.
..but we have the reissue 5881. they do the job and we have them goosed nicely in the blondeshell.

tvthewiredturtle wrote:

I'm Incinerator wrote:

tvthewiredturtle wrote:

I'm Incinerator wrote:

that's interesting about the JJ 6V6's. A good option for tubes for a 6G6-B as well

Is EH the only one reissuing 5881's? I thought I heard that TAD has some small bottle 6L6's or 5881's that were decent?

EH has the name for the small bottle 5881

the tad tube is a small bottle 6L6GC, its not bad but less distinct in tight lows

Where is a decent place to get NOS 6L6WGB's and 5881's?
Dougs tubes
Also, in your opinion what would be a good tube set up for more marshall flavor out of a 6G6-B...or do speakers play more a roll in that? I'd imagine a good KT66 wouldn't hurt either.
The tubes I'm talkin about get the amp to clip much sooner, any big bottles are gonna milk full power from the amp's 50watt prowess

I forgot that a set of 5881's or 6L6WGB's are putting out less wattage than a set of 6L6GC's or KT66's would. How much do you think a set of JJ 6V6's put out? The JJ power tubes are pretty stout! I have a set of the EL84's in my CR and they make the CR a punchy rock machine.

I should have guessed dougs tubes, I guess I've never veered away from the EL84, 12AX7, and GZ34's.

Dont know what to say about the JJ's, that was just a suggestion based on their specs and some Tube jockeys that comment on them. I've used them for
my princetons and in tophat super deluxes.

regarding doug's tubes.. I have to use them because my whole suppliers are no longer carrying them as the stock is drying up. They went from $40 a duo, to $80
just in the last few yrs and I know its gonna just get worse.
..but we have the reissue 5881. they do the job and we have them goosed nicely in the blondeshell.

Crazy! I think I can retube my whole CR for about 70 or 80 bucks. I think I would only need one or two duo's of NOS tubes for recording or if I get another 6L6 based fender. Hey, if the reissues sound good I will be happy

one thing...

important...

Big Iron

nothing like playin your gretsch guitar through
4x the iron

tvthewiredturtle wrote:

one thing...

important...

Big Iron

nothing like playin your gretsch guitar through
4x the iron

Is that what the Blondeshell is packing? Those almost look like iron from a DR103!! HEAVY!