Modding my 900! (All tube, with clips)

[iron broadsword]

Iron broadsword, the link to your video seems to be dead. It says file not found.

Hey Thank’s Iron !...Still Rock your 900 ?

Also , what’s the best bias for this mod ,
got some new EL34 JJ’s .

I'm still rocking it.. it's my go-to amp for lead tones and anything else my class 5 can't do by way of marshall sounds. I just recorded this with it actually. I used a dual recto for the rhythm but the lead is all 900DR with almost no processing.. just a little bass removal and compression.

I can't remember what I biased it at tbh

 

[Kelia]

I'm still rocking it.. it's my go-to amp for lead tones and anything else my class 5 can't do by way of marshall sounds. I just recorded this with it actually. I used a dual recto for the rhythm but the lead is all 900DR with almost no processing.. just a little bass removal and compression.

I can't remember what I biased it at tbh

Great playing and killer sounding !!
Thank’s for posting this !!
Tschrama suggest that I do the mods so
brought the amp to the tech today to have the whole shabbang done so should get it next week !

I’ll ask Tschrama for the bias if he doesn’t read this post !.......He’s been so helpful!
Lot’s of nice folks over here !!....

 

[Kelia]

yeh... undo these other mods.

Good day Tschrama , the amp is at my tech’s place , I know it was biased from the previous tech before I bought it but maybe it’s a good time to tell him to check the bias , what the best bias for this amp with your mods ?

Another question I have ,.... I see that everyone seems to like the 900 MKIII more and the DR less , after the mods ,
what are your thoughs between the DR vs MKIII ?


Cheers !

Lou

 

[tschrama]

Dont worry about bias. I sincerely doubt any bias advice, except to keep it low... around 25-30mA, for any amp, any tube. For this reason I get flamed, but seriously, my own amps don't sound any better at 35,40mA etc etc.. I like them just as well at 25mA.

I prefer the modded DR over a stock MKIII, but then again, a modded MKIII will be even better

Let us know how it turns out!

 

[Kelia]

Dont worry about bias. I sincerely doubt any bias advice, except to keep it low... around 25-30mA, for any amp, any tube. For this reason I get flamed, but seriously, my own amps don't sound any better at 35,40mA etc etc.. I like them just as well at 25mA.

I prefer the modded DR over a stock MKIII, but then again, a modded MKIII will be even better

Let us know how it turns out!

Thank’s !...........will surely do let you
know how it sounds and feel and hopefully make a small clip !

The guy who sold me the DR is also selling his MKIII , just curious why a modded MK3 would be better , is it something inside or some components
that are better made or the layout?


Lou

 

[tubes]

I'm still rocking it.. it's my go-to amp for lead tones and anything else my class 5 can't do by way of marshall sounds. I just recorded this with it actually. I used a dual recto for the rhythm but the lead is all 900DR with almost no processing.. just a little bass removal and compression.

That's nice lead sounds on 'Today we Forge...'

Good playing too: it ended with style - good sound, leaves us satisfied but also wanting more.

 

[Kelia]

Dont worry about bias. I sincerely doubt any bias advice, except to keep it low... around 25-30mA, for any amp, any tube. For this reason I get flamed, but seriously, my own amps don't sound any better at 35,40mA etc etc.. I like them just as well at 25mA.

I prefer the modded DR over a stock MKIII, but then again, a modded MKIII will be even better

Let us know how it turns out!

Hi Tschrama !
I got the amp yesterday ,
I think it’s a very good amp now but my problem is that I can’t play it too loud where I live and it seems to want to roar but can’t at lower volumes !
I’ve allways played plexi’s and I find I could play them better at lower volume ,
with a good MV , it sounded smooth grain wise !.........I’ve noticed that my Presence control is not working anymore
so might have it checked .
Very different than a Plexi , is there a trick to have the grain sound smoother ?

Thank’s ‘!


Lou

 

[marshallmellowed]

Sounds like the negative feedback was greatly reduced (resistance value increased), which will greatly decrease (or eliminate) the effect of the Presence control. It will also add some "ice pick" highs, unless compensated for with added capacitance.

 

[tschrama]

You should really take this up with ur tech.

The mod quoted here doe not involve the power amp at all. Presence and MV shouldnt be any different.

Sound to me like a very different mod is done. It should be smooth, with lots of room for the Treble and presence pot to dial in any amount of grain or sizzle.

Can you post a gut shot?

 

[Kelia]

You should really take this up with ur tech.

The mod quoted here doe not involve the power amp at all. Presence and MV shouldnt be any different.

Sound to me like a very different mod is done. It should be smooth, with lots of room for the Treble and presence pot to dial in any amount of grain or sizzle.

Can you post a gut shot?

Thank’s !

I might take it to another tech to check whats going on , I’ll post pictures if I get a chance!

 

[Kelia]

You should really take this up with ur tech.

The mod quoted here doe not involve the power amp at all. Presence and MV shouldnt be any different.

Sound to me like a very different mod is done. It should be smooth, with lots of room for the Treble and presence pot to dial in any amount of grain or sizzle.

Can you post a gut shot?

Going to the tech tomorrow , amp tech , not tv tech ,I’m sure the tv tech is good but he doesn’t try the amp after it’s done so that is why he never heard the Presence was not working and maybe something else .

 

[Kelia]

You should really take this up with ur tech.

The mod quoted here doe not involve the power amp at all. Presence and MV shouldnt be any different.

Sound to me like a very different mod is done. It should be smooth, with lots of room for the Treble and presence pot to dial in any amount of grain or sizzle.

Can you post a gut shot?

So the tech opened it up yesterday and said that the other tech installed ElCheapo parts that are not tone friendly
so he’ll check everything and will fix the Presence knob not working .
He tried the amp and there was not a lot of note diffinition !
A few pots are scratchy and jumping from mellow to brutal instantly so this too will be addressed.

 

[tschrama]

learn to solder urself! Do be a slave to those f#$% so called techs.

Part quality doesnt do anything bad or good for ur tone. He is just emptying ur pocket.

get urself some deoxit spray and/or a dry air spray and clean ur pots.

The 1st tech didn't do R17 and didnt do R13. Nor did he do R2.

 

[tschrama]

check this pic.

 

[Kelia]

check this pic.View attachment 46813

Jeez !...He told me he did everything !!!

Thank’s Tschrama for your help!

I must say that Patrick , the amp tech really knows what he’s doing and is very honest and allways suggest whats best for the client even if he won’t mod or build anything !

 

[Kelia]

check this pic.View attachment 46813

Must be why I wasn’t too impressed!

 

[Kelia]

Hello Tschrama ,
the amp is ready and my tech fixed everything and said that it sounds better
so should pick it up in a few days .

Can’t wait yo try it !

 

[Kelia]

You should really take this up with ur tech.

The mod quoted here doe not involve the power amp at all. Presence and MV shouldnt be any different.

Sound to me like a very different mod is done. It should be smooth, with lots of room for the Treble and presence pot to dial in any amount of grain or sizzle.

Can you post a gut shot?

Ok so now I see what you mean !!
Got the amp today and it’s a totally different amp !!
Sounds way better , more clarity and a lot warmer than before !.......and for some reason , the amp is a lot quieter which is great !

One thing I’d like to have even if i know the 900’s need the volume to deliver would be to have more bottom thump so I could practice at night ,.....any suggestions ?

Tx Tschrama !!............everyone who owns a 900 should do this to enjoy their amp more !!!...........Well done !!

 

[Kelia]

 

[tschrama]

Ha.. glad it worked out for you!!

More thump canbr easely done. But I am bit busy right now.... Remind ok? contact me via www.sgravenmadeamps.com