I want to upgrade my Marshall VS15

[szklemen]

Hello all! My first post here!

I own this little amp, Marshall Valvestate VS15 for over 10 yrs now, and there's need for speaker upgrade.
Primarily this amp serves as my monitor (I connect my Rocktron Utopia directly into PA) and it's 8" speaker doesn't
do my ears well 
So I wanted to upgrade to 10" speaker and was told by some not to do that, and by some - go ahead!

I decided to go ahead - but then I thought that maybe it would be possible to upgrade some components
also and make that - say -25-30 W amp?

If there's someone familiar with this circuitry (it's not an MG series) and possibilities of that kind of upgrade -
I'd like you to comment on that.

Thanks in advance!
Klemen

[joecool85]

Hello all! My first post here!

I own this little amp, Marshall Valvestate VS15 for over 10 yrs now, and there's need for speaker upgrade.
Primarily this amp serves as my monitor (I connect my Rocktron Utopia directly into PA) and it's 8" speaker doesn't
do my ears well 
So I wanted to upgrade to 10" speaker and was told by some not to do that, and by some - go ahead!

I decided to go ahead - but then I thought that maybe it would be possible to upgrade some components
also and make that - say -25-30 W amp?

If there's someone familiar with this circuitry (it's not an MG series) and possibilities of that kind of upgrade -
I'd like you to comment on that.

Thanks in advance!
Klemen

It's unlikely that upgrading the internals to get more wattage is simple or practical - you had it right doing the speaker upgrade.

[J M Fahey]

Agree.
It can sound surprisingly well driving an external 2x12" or 4x12" ....... like most other "practice" amps.
In general, coming from a "serious" company (Fender, Marshall, Peavey, Laney, Crate) the electronics are good, it costs the same making them sound good or bad, so ....
The real difference lies in the cheap speaker and minuscule cab.
ZZTop was famous for using a tiny Marshall 5005 (SS Lead 12) as a preamp, driving big PA rack type power amps and mountains of speakers.

[szklemen]

Thank you  :tu:  for your replies!  8|

I guessed that making it more 'powerful' would be a mission impossible - but I had to ask  :duh

Now, two more things to ask  if I may 

- this practice amp's enclosure is all made of chipboard covered with false leather kind of material.
   Front board (where speaker is) has measurements of 13,4" wide and 10" high and I guess I'd have to make 2 new elongated sides for this combo enclosure.
   So I was wondering how much height would I need to install 10" speaker?  Would 13,4" x 13,4" be enough for speaker installment and working/breathing/vibrating?

- factory setup of the cabinet is half open back; and when I put 10" speaker should I leave the cabinet half open or increase to 2/3 open, or even 3/4 open?
   Does that depend on the speaker type?

Thanks!
Klemen

[szklemen]

I have been reading about amp wattage/speaker wattage ratio;
and I found out that in a single speaker option (cabinet or combo) wattage of a speaker should be 3x greater than of the amp that runs through it.

Question:
So, if my amp has 15 W RMS with 8 Ohm speaker, my speaker should be 45 W minimum and my amp wouldn't be too weak to drive it? I'm I wrong?

[J M Fahey]

2X is enough, but more is no problem at all.
As of driving a large cabinet, on the Noisy Cricket thread watch a Smokey amp (0.5W RMS) driving a 320W 1960 4x12" Marshall cabinet.

[szklemen]

Thanks for the input!
I was told, when I gave my amp to the repair shop for some pot changing, that they tested it with 4x10" cab and it sounded great..
Someone told me they must have run it like preamp through some amp, but I didn't ask..
In this case I'll get the best possible that I can get.

Was looking at http://www.adamhall.com/en/Eminence_Legend_GB128_-_12_Speaker_50_W_8_Ohm.html
I says - Sensitivity 101.4 (is that dB)

[J M Fahey]

You may make a brand new enclosure for your 12" speaker, and use the little combo as a head.
But I think it needs a 4 ohm speaker.
I think Eminences are available in 8 and 16 ohms only.
Consider some Jensen MOD speakers: they can be ordered in 4/8/16 ohms , sound very good, and the price is excellent.
Search around.

[szklemen]

My amp's specs says:
Output 15 W RMS - 8 Ohm

And yes, I thought about new enclosure for 12" speaker and head out of this one

[szklemen]

Consider some Jensen MOD speakers: they can be ordered in 4/8/16 ohms , sound very good, and the price is excellent.
Search around.

Alas, in my country there's only one importer of Jensen speakers and he's pricey.. and as I explored a bit further, not willing to send it by mail.
And Eminence dealer is just 20 minutes away from my place.

Edit:
Would there be a problem (like burning my amp) if I install 4 Ohm speaker?

[J M Fahey]

No, you are matching an 8 ohms speaker to your 8 ohms amp; I thought you had an earlier Valvestate which preferred 4 ohms.
What Country are you in?
Maybe you can buy the Jensen (or any other, even the Eminence) by mail and save some $$$ for sure.
Most Customs/Mail in the World charge nothing for up to U$50 products, and you would have to pay for the difference only if you spend more.
Many times they just deliver it to your door with no questions asked
Now if it´s "electronics" it´s different, but a single speaker, alone in its cardboard box, looks too innocent to them.

[szklemen]

I'm in Europe, Croatia. I will ask around if anyone ordered Jensens from abroad.. I read a post on local forum that someone asked a friend who was on a business trip in Italy to buy some speakers for him. I don't know anyone who goes to Italy.

And If I connect (by mistake) 4 Ohm speaker on my 8 Ohm amp - will I burn something? Speaker or amp?

[J M Fahey]

Thomann Deutschland, Europe´s largest cyberstore, ships *anything* to Croatia (Hrvatska) for a fixed price of 25 Euro, for a total order weight of up to 31 Kg.
So it may be good for you to buy 2 or 3 things with some friend so you share that shipping cost amongst you.
For a single 4 Kg speaker it´s too much.
For 7 speakers it´s less than 4 Euro each, very cheap (just as an example)
http://www.thomann.de/gb/helpdesk_shipping.html?xsid=78e694ace2e1404350c86f2bd97626be&country=cro
To see what they have to offer:
http://www.thomann.de/gb/search_dir.html?gf=guitar_amp_speakers&sw=guitar+speaker
As a curiosity, post what your local Eminence distributor charges and for what model, just to compare.
*Maybe* it´s cheaper than ordering direct, don´t know.

If you connect a 4 ohm speaker to an SS 8 ohm amp, it won´t burst instantly into flames, but will work much hotter than normal, not good.
Probably no problem at home for a short time, but for a Saturday night show, full power, at a local bar .... may be fatal.
If you go the other way, (8 into 4) nobody will suffer, only you will lose some power.

[szklemen]

If you connect a 4 ohm speaker to an SS 8 ohm amp, it won´t burst instantly into flames, but will work much hotter than normal, not good.
Probably no problem at home for a short time, but for a Saturday night show, full power, at a local bar .... may be fatal.
If you go the other way, (8 into 4) nobody will suffer, only you will lose some power.

My friend said he's got one speaker cab 12" leftover that he used in
bass - amp - cab combination, but he's not sure about Ohms in that cab- is it 4 or 8..
..so I wanted to try it out, but didn't want to blow everything up...

[szklemen]

As a curiosity, post what your local Eminence distributor charges and for what model, just to compare.
*Maybe* it´s cheaper than ordering direct, don´t know.

I've looked into his price list, but it's from last year and prices are various - 'round 10€ more or even 2-3€ less
for cheaper models (in compare with thomann), but as I say it is an old price list. Shipping costs would be ~10€.
But, distributor won't send it by mail or UPS. I'll try to call and see what can be done.

So, I guess, in the end it's probably around Thomann price, anyway.
I do have some friends in Germany, they could probably do me a favour  <3)
Thanks for the input!
***
Are Jensen speakers better than Eminence or is it 'cause Eminence produces theirs in China (I've read something in some thread here)?