this sounds like bulls**t to me
rob w
Does this sound like bull, it does to me.
My sons 16yr old friends old marshall amp ( 100 watt transistor) gave
out a puff of smoke and stopped working, he took it to our local
marshall dealer who sent it to a local tech, 50 pounds later he gets
it back , works for 5 minuites and goes puff again.
He took it back and explained what had happened and in passing said he
was using a 5 string passive bass ( its a lead head).
He got the amp back saying that it was damaged beyond repair due to
him using a passive bass and it had overloaded the input channel and
burnt it out and even worse some of the damage was due to it being a
Five string.
This sound bull to me the bass could not burn out the channel, it
might overdrive it to distortion yes but not burn it out. and because
its a five string???
If its is bull ill go with him and have a word i think he should get
his 50 pounds back anyway, but my guess is the tech is not very good
what do you people think.
Rob
Steve D
understand how it would damage the input stage because thier is very
little current flow in the pre amp stages and the have by-pass caps in
series with the signal path that are very frequency dependent meaning
they will not pass lower frequencies as well as higher frequencies.
Second of all this is a SS amplifier not a valve amp. If it were a
valve amp it is possible to damage the output tranny by driving it
with low freqencies that it cannot pass.
You run the risk of damaging the speakers with a bass guitar more so
than damaging the amplifier. It is possible to damge the output stage
but I am not convinced this is the case. I must say I also have never
heard of an amp damaged beyond repair maybe damaged beyond fiscal
sense to repair. I fear the tech F'd up and using the bass as an
excuse to cover up. What probably happened he fixed it the first time
and overlooked something that was damaged and then it damaged the same
section the next time around. SS amps are notorious for chain
reactions when things let go. Old Sansui SS recievers were notorious
for this hence the saying when a "Sansui goes cablui it's time for a
newui". This amp is not ideal for Bass but I do not believe it to be
the root of the problem but more info would be helpful. Ask them what
section is damaged the input stage or output stage. Then ask them if
the damaged buy the Bass then why did the Tech not pick up on this the
first time around but instead he just fixed it and took his 50 pounds.
I will hold my final decision until you can get more info.
HTH
Steve
rob w
when i get time , by the way i made a mistake and its a active bass.
Ill let you know the out come.
Rob
mk182_
Valvestate?
I know valvestates have tubes in their preamps . .
anyways, you're not supposed to plug basses into guitar amps, it's
common sense. And a 5 string bass does get some really low end . .
rob w
Its an old ... very old solidstate not sure of the model as its my
sons mates so ive not got it at hand.
Im unsure of this not using a guitar amp bit as i dont think that the
lead / bass / keyboard/ vocal amplifiers are actually any differant in
reality after all you use the same type of PA poweramp for the subs as
you would for the horns. and yes a five string do get low but i still
cant see how freqency can burn an amp out.
The tone may not be the best but shit he's 16 and playing in my
garage, when they,if they ever do gig on a regular basis im sure he
will try and get a better amp.I just hate to see a kid ripped off. Rob
smoki...@hotmail.com
This tech is talking rubbish I'm afraid......admitidly it's not agreat
idea to play a bass thorugh at guitar ampo especially at any kind of
volume, but if anything would be damaged then it would be the
speakers, not the amp itself.
Bear in mind in the early 60's bands would often put bass and guitar
through 1 Vox AC30 as this is all they had!!!
Sounds like he's f~@ked something up and is covering his ass....
Al
robw...@yahoo.com (rob w) wrote in message news:<e63bb3bf.03071...@posting.google.com>...
mk182_
off.
I was just always told never to plug a bass into a guitar amp! Look
at most bass amps, they're like . .. 200-400 Watts . . . because the
amp needs more power than a regular guitar amp to handle the bass.
That's probably why the amp, uh, exploded
Steve D
I agree that this amp is not ideal for bass but saying bass amps are
200-400 watts really is not a fair comparision look at the old fender
bassmans granted they were better guitar amps then bass amps they were
only 45 watts or so. Paul McCartney's bass amp one Love Me Do was a
Leak TL/12 12 Watt amplifier attached to a Tannoy Monitor Speaker
granted it is not pounding Bass. Look at the Crate BA-15 15 watts of
power. They need that power to get the room pounding not to handle the
Bass. It is very true that most big Bass rigs are high power that is
to get that pounding bass but If the tech is saying that the pre-amp
section blew up because of the bass I can't buy that because if you
run a simulation through Marshalls tone stack wich ironicly was bassed
on Leo Fenders old Basmann it really attenuates the low freqency
content and the pre amp is not a power amp it is a voltage amp so very
little current flows in this part of the amp. Another thing to look at
is a bass is three octives lower then a gutiar, a guitars A string is
440hz so one octive down is 220Hz two octives down is 110Hz three is
55hz But a five string Bass has an open B string that is 30.9Hz most
consumer grade home stereos are flat down to 30Hz and they have wimpy
output stages. I am not saying that the bass did not contribute to the
failure but I believe the amplifier had other issues leading to the
amp giving up the ghost. The reason I am skeptical is he fixed it the
first time and took the 75 quid and then when it failed again he said
it was damaged beyond repair after he found out a bass was running
through it.. come one I've been repairing amplifiers for a long time
and I have yet to find a Marshall Head that is unrepairable maybe to
expensive to make sense to repair. If the amp failed in the power amp
stage or the speakers were blown I would blame the Bass but since the
pre amp was damaged makes me think the tech missed something and is
looking to get out of making it right I believe the tech should fix it
for parts cost and then run a guitar through it for a few weeks and
see if it fixes it or see if it gives up the ghost again.
Al LePage
frequencies though the preamp stages to the transformer since the pots arent
designed to respond that low. Capacitors are the big issue for a bass amp.
They need more and bigger caps to respond to the intermittant transient
spikes of low frequencies. My sons Marshall Superlead 100W is basically a
SuperBass with a change of pots. It has 6 caps!! the newer 2203 have 3. The
only thing a bass guitar can do to a guitar amp is blow the speaker voice
coils on a combo....or just sound crappy through an amp not meant to
transmit those low frequencies. IA guitar amp just wont sound good as a
bass, the low frequencies just dont get amplified. It doesnt pick them up.
Your amp tech repaired the symptom and not the problem. Something in that
amp is causing the problem and its not the guitar!!!!
"mk182_" <mkuhn...@place.dawsoncollege.qc.ca> wrote in message
news:ee064482.03071...@posting.google.com...
proletariat
news:e63bb3bf.03070...@posting.google.com...
yes, that is most definitely BULLSHIT
any Marshall amp in good working order can be used with *any* electric
guitar or bass
go get your 50 pounds back
Walker Texas Plumber
Yeah - that tech is giving you a line of crap if he said those things.
Make him repair it properly or goive the money back if he can't.
Are you sure you are using the correct speaker load for that amp?
The 5 string bass makes NO differece at all.
If this is a solid state amp and something is shorting out the
speaker load (such as a damaged voice coil) then THAT could
cause the problem, but NOT a 5 string bass!