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Messages - solidstate2199

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1
To me the most obvious difference in the preamps ss vs tube
Is the onset "fizz" of the opamp or generally transistor when it
Starts to clip. At least i figure this is from transistors because all ss
Amps that i have do it.  I have a marshall 3203 which, if it wasnt for
That fizziness would sound rather close to a marshall 2204 or similar.
Maybe its just bad design from the old marshall ss amps.
Maybe jfet dont fizz.

2
Hello, my Questions for this Project for people
With better understading of Transistor Phaseinverters.

I want to build a Standard Superlead Preamp in one of my
Solidstate 2199 SS Amps, but i want to build it with the tube
 phase inverter stage. The thing is, if i build a superlead and put
A ppimv inside it, why do i need the el 34 and the output transformer
If i cant play that loud to beginn with? The poweramp isnt working
Until it probably to loud.

So i want to build this unit for homeplaying and small gigs, 30 watt
Out of that old marshall ss should be plenty.

But i have problems understanding transistor pamps...
The 2199 has a socalled quasi complementary design..
Is it possible to inject the tube phase inverted Signals
Into this 2199 power stage and where?

Thanks the schematic i could upload or just check it
At drtube website.

Cheers


3
Tubes and Hybrids / Re: Cooked Super Amplifier
« on: March 09, 2020, 02:16:20 PM »
Im in the process of getting this Superlead repaired in the next couple
Weeks, the Feedback resistor is not bad, it had Carbon residue on it
From blown screen resistors next to it.

FIRST The filter and reservoir caps need to be Done. Currently there
Is a voltage of over 1200 volt inside due to the leaking caps, i couldnt
Believe it, i measured with different multimeters.
I think the dmm is not getting the right reading because of the stray
Ac...but nevertheless...it also needs a thorough cleaning because
There is carbon everywhere...the pt sockets need to go.

I hope the transformers are alright.

4
Tubes and Hybrids / Cooked Super Amplifier
« on: May 20, 2018, 07:45:20 AM »
Bought an old Superlead Style Amp, its not here yet.

One burned out EL34 Socket and what looks like the
negative feedback resistor is shot, plus collateral
to the surrounding parts.


There is a cable coming from the 16ohm speaker jack going
to that resistor so i guess it is the 100k seen on the schematic.

Can i suspect output transformer damage?

I make better pics when i have it here.


schematic
https://drtube.com/schematics/londoncity/dea100-early.gif

5
The Newcomer's Forum / Re: Marshall 5010 Needs Help
« on: May 14, 2018, 05:14:59 AM »
I had the 5275; Mosfet 100; Lead 12, Artist 3203 , Marshall 5010, Valvestate 100, JCM 900 Dual Reverb...sorry to say this but good Marshall is not happening with any of those...cut the chase and get real.

(1959 2203 2210 JTM45)x(PPIMV and or Attenuator)=ROCK

Could very well be that your 5010 has a transitional circuit from the
earlier Marshall SS Amps, and i can imagine that sounding not pleasant.

The mid 80s 5010 do a generic
ACDC Sound, nothing more or less.

6
The Newcomer's Forum / Re: Marshall 5010 Needs Help
« on: May 02, 2018, 10:25:02 AM »
Hi
i havent read the whole topic yet but i know the answer to your 5010
"buzzing background" sound...
this is NORMAL behaviour on the 5010.

What you hear is the Ampsound with gain on 10 as a low volume
background noise.
It is a lets call it "design flaw".

The 5010 is only put to good use with the gain on "10" forget it for cleans and
use it like youre supposed to as a "practice 2203" .

I recall that the background fizz at low gain settings is not all that noticable
at higher volumes...so try the Amp with the Master volume turned at least to 6
and forget about playing totally clean gain has to be at 7 for some hendrixy tones.

Good Luck...the 5010 is a good sounding SS Marshall if used properly
for 80s Hardrock played with a higher output Humbucker.

(all IMO)

(a lot of the 5010s have a problem with oscillations at high gain settings,
i have seen so many with this problem that i think its a design flaw too.
Marshall changed a lot of stuff in their solid state amps of the 80s, lots
of revisions.

7
Thanks for the tip Enzo, :dbtu:

i will try the oldschool duct tape trick or
McGyver me some beamblockers.

8
Hi Guys,

as always thanks for your tips and suggestions,
much appreciated.

I wanted to give a little update on my initial post
regarding the Marshall 2199 Oscillation problem due to
a nuked out capacitor.

I did the repair the other day, replaced the knocked off capacitor and
et voila! the oscillation is gone.

To my surprise this particular 2199 out of my currently 3 sounds
definitely better than the other two. Nice classic 60s to early 80s
Marshall crunch can be achieved. The sound doesnt get overly harsh
like on the other 2 and all 3 Inputs can be used, even the bright one.

With this model its really hit or miss. One big downfall
is the cabinet construction, its very "beaming" as soon as you step
a little away to the side the perceived sound gets very mushy.

Still, im happy that this one works properly now and doesnt sound
as bad as the other two.

Cheers.

9
Amplifier Discussion / Re: Marshall Lead 100 MOSFET 3210 Head
« on: June 23, 2017, 11:31:40 AM »
Hi there,

i have a 3210 and some other similar 80s Marshalls.
I use the amp once or twice a week for some years now
and never had any issues with it. (1965A+B)

I go with the first response and say dont do anything if not
necessary.

Mine has a little hum, probably 60hz, could be the caps or its normal,
because my 5275 which is bassically the same circuit has it too.
Or this hum has something to do with the Reverb Circuit, because
if you put the Reverb Knob on half without engaging the Reverb,
the hum lessens a little..80s Marshall Reverbs are always noisy in my
experience.

And this Amp pops sometimes when powering down, this is normal on
this model. If you dont want it to pop leave it on for about 10 minutes after
playing, if you switch off then 9 out of 10 times it doesnt pop.

Hope this helps.

Its a nice Amp, sounds nice, just feels a little stiff to me when i play,
has a hard attack.

Have fun.

10
Tubes and Hybrids / Re: blown filtercapacitor in 100watt. Why?
« on: March 01, 2017, 03:25:35 PM »
Thanks for your answers,

it probably wasnt just up to the task or maybe age.

This amp has an obnoxious "bass boost" at low volumes.
For anybody interestet in the AOR Amps here is my very simple solution for this,
it works wonderfully, no need for mods...

I simply take my trusty Alesis Microverb rack unit in the Effects loop, that way you can turn the
Master Volume on the AOR higher and take the volume down on the Effects-Unit Out.

The Louder you turn your Master the more useful the Bass-Boost gets...without the rack Unit
the bass is way too much with the boost pulled, and without it it lacks...

use a rack unit and all good...or play that thing as loud as it gets, i do that anyways.

plus, i dont understand what the fuss is about the effects loop being not useful, it work fantastic
with a line level rack unit..maybe if you try to use pedal which want to see instruments levels...could be.

I havent checked the bias yet..i probably come back to this thread anyways..

Thanks

11
Tubes and Hybrids / blown filtercapacitor in 100watt. Why?
« on: March 01, 2017, 01:03:42 PM »
Hi Folks.

i bought a 1988 Laney AOR which works fine. Nice Amp.

One thing which caught my interest is that one of the 6 filtercaps
has been changed sometime ago.

As i open all my new amps to check the overall condition i discovered that
this capacitor must have really blown wide open because there were lots of
residue in the headshell directly under that spot.

What causes this? All other 5 L.C.R. caps looking fine without any dimples on top due
to age.

Im curious to what causes such an event. I guess too much voltage? (caps are 50uf/50uf 500vdc)

Thanks for your insights.

12
Tubes and Hybrids / Re: Bias Question regarding Marshall 100watt 2203
« on: February 13, 2017, 05:12:27 PM »
Greetings Enzo,G1 and Phatt!

Alright so i have to divide /2, thanks!

Some pictures.

















I agree, it looks like somebody got careless with the iron.
Someone reflowed one half of the output-jack joints, these are
the only very shiney looking joints, plus one rectifier diode
has been changed sometime, probably earlier.

Probably just coincidence that this tube socket of the worn
"looking" Pentode was infront of that jack. There is no excessive
heat in that area, as of now. The socket looks fine like all others.

I understand the voltage drifting up and down alittle,
perfectly normal like you guys said.
The webpage i got my information from on "how to bias" said
i should take the voltage to 3 decimal places, which firstly my cheap
dvm doesnt do at high voltage and there is no point anyways if there is
drift.

I will get a bias probe socket and some good clipping probes
these days to compare.

Phatt you were right, there are no dents in the plates, looks like these are little
particles of the mica-material. Still,only on this one tube?

Here are the measurements:

Screen-Resistors: t1=985ohms/t2=992ohms/t3=1035ohms/t4=1010ohms
(checked without desoldering and with tubes in socket!) i guess they are fine?

Neg.Bias-Voltage: t1=-34.6V/t2=-34.6V/t3=-34.5V/t4=-34.5V (pin5 to grnd)

Screen-voltage: t1=435V/t2=435V/t3=436V/t4=436V (pin4 to grnd)

Shouldn't the screen-voltage be higher than the plate voltage?

Also, the L.C.R. Caps are made in 1982, have dimpled tops but still i can
not hear any unexpected hum...swap for new ones?

One thing puzzles me about this amp, it has 8 rectifing silicon diodes
were the Marshall has 4, everything else is the same. Can someone
try to explain to me why that is...easy beginner here  :).

Thanks for your insights!

13
Tubes and Hybrids / Bias Question regarding Marshall 100watt 2203
« on: February 13, 2017, 06:36:19 AM »
Hi,

i bought a Marshall 2203 Clone.
100Watt, 4xEL34 3xECC83
It works flawless after thoroughly cleaning the dreaded Cliff-Type
Jacks (closing contacts).

The one thing that concerns me is that one of the EL34 looks way more
used than the other 3. After opening the Amp i discovered that the
loudspeaker-jack directly behind this particular tube-socket is slightly
melt, nothing drastic but it indicates that this tube has or maybe had some
sort of problem, it maybe draws more current was my first guess.
Or maybe the 1k5w screen grid resistor is not o.k.?
Note there is no sign of redplating or any other malfunction on this tube,
but all of the lettering is gone and i can see lots of little dents on the anode,
while on the other 3 the lettering is intact and there is absolutely no sign of
dents on the anodes.

These are original AEG (made by RFT, Eastern Germany) EL34 tubes, so i want
to keep those as long as they work.

I was checking the bias via the "Output Transformer Resistance Method".
My measurements as follows:

plate voltage: t1 - 440V (blue side); t2 - 440V (blue) ; t3 440V (red) ;
t4 - 440V (red) - !measurements were not stable, they varied between
439V to 441V over a period of 30 minutes, so i took the middle for all tubes!

output transformer centertap voltage: 440.5V ( varied between 440V to 441V)

voltage drop across half of the output x-former primary: 440.5V-440V= 0.5V

output x-former DC resistance measured with unpowered but warmed up amp:
red lead side=16.3ohms
blue lead side=17.6ohms

anode current blue side: 0.500v/16.3ohms=0.0307A or 30.7ma
anode current red side:  0.500v/17.6ohms=0.0284A or 28.4ma

HERE IS MY QUESTION! DO I HAVE TO DIVIDE THIS CURRENT /2 BECAUSE
THERE ARE 2 OUTPUT TUBES PER SIDE IN PARALLEL?

If so then this amp is biased very cold (27% red side, 25% blue side)

WHY IS EL34 NR.1 (t1, next to phase inverter ECC83) MORE WORN TO THE
EYESIGHT THAN THE OTHER 3? IT DOESNT GET MORE HOT THAN THE OTHER
ONES AT IDLE, MAYBE IT DRAWS MORE CURRENT UNDER MORE LOAD?

Any help welcome.
Thanks







14
The Newcomer's Forum / Re: Marshall 5010 30 watt Master Lead Combo
« on: December 01, 2016, 09:23:21 PM »
I am pretty sure its a bad solder joint on the "High Input" Jack
or its somehow defectice, dirty i think not i used good contactspray on it
which otherways always worked if something was slightly corroded.

Here i found another thread  whith a similar Marshall with exact same symptoms.
So 2 times it was the jack, it points in this direction.
Ill give it a close eying these days and try resoldering first and then replacing.

This is probably very common on the 80s Marshall Solid State Amps.


Thread Marshall 5210 squeal question

Code: [Select]
talk about a wild goose chase!!
The switchcraft input jack was it!
The  board wasn't grounding properly on it's mounting post and the amp was grounding the chassis through the input jack causing a ground loop.
It sounds far fetched, but i could duplicate and repeat this condition.
I'm going to order the correct jack.


15
Amplifier Discussion / Re: Marshall 2199 cap replacement oscillation issue
« on: December 01, 2016, 04:57:29 PM »
Hi i want to update my thread because i have bought the 5010 amp
now, which i wanted the 2199 (modded) to sound like.
these amps are day and night.  the 5010 has a very classic acdc to 80s
metal rock distortion- you cant do that with stock 2199.

which i really liked about the 2199 was the ability to go from moderate crunchy to
very clean just with the guitar volume, i mean really clean not marshall clean.

i really hoped i could do that with the 5010 to and i have to say that it doesnt do it.
it goes clean(ish) but not that amount. sucks.

here my personal resumee.. i tried many of the 80s and 70s marshall solid states,
infact almost every model, plus the first valvestate 8100 100watt head,
mosfet head, 3203 Artist Hybrid Heads and none of these can do what their tube equals can do (2203/04;2210/05).

Either they plainly sound shitty, feel shitty,no sustain, dont clean up with the volume, are dull, the 8100 doesnt even slightly clean up it just get more mushy till you cant hear it anymore.
i really wanted to have the solid state thing work out for me...but it just doesnt.

i tried fender and vox solid states too, not much better or worse.

maybe its just me but i think i sell all my ss of and get 1 or 2 good old tube marshalls
to end the charade. peavey supreme or xxl i will maybe try out, but i have no good feeling.

i dont want to break loose any tube vs solid state campaign but it seems like it doesnt
work for me. to me the marshall 2203/04 has it all, power, big bottom end,master volume so you can even play it on bedroom volume with preamp all the way up and it sounds better than all (good!) Marshall SS together, roll back the guitar volume and it cleans up very good. even the 2210 channel switcher cleans up as good.

Does anybody know of a solid State amp no matter what maker that does this well,
playing a good distorted rhythm sound roll back and have a nice real clean sound which isnt much much lower in volume than the full on sound?
cheers

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