musicman speaker replacement

[evgdboy]

hi
i'm gonna change the speaker in my musicman RD50.
i know someone selling an eminence patriot, red/white and blues
12 in 8ohm with low usage at a good price.
the speaker is rated at 120 watts RMS
the amp is only 50 watt RMS

right now on any given night i'm called to play many different styles
of music....jazz, cntry, oldies rock etc..
i get most of my distortion from pedals when i need it.

should i pass on the patriot and get something a bit closer i to the 50 RMS of the amp?
the stock speaker in it now is ok but, sounding kinda tired.
i want something with a lil more bite more but i don't wanna go off the deep end.

ideas...suggestions etc...
thanks

[cynical1]

evgdboy -

Greetings and welcome to the board.

If you're getting a good deal on this Patriot speaker, then you're really not going to want to hear this...

The generally accepted rule of thumb is around twice the amplifier wattage to the speaker wattage. Again, this is not cast in stone, but it's pretty common wisdom.

So, if the loudspeaker you have is 100 watts, you're going to match this with a 200 watt amp.

There is a reason for this. At 50 watts your amp will clip out trying to drive the 100 watt speaker. The clipping will overheat a loudspeaker faster then overpowering it...thus shortening it's life span accordingly.

You want the amp to have reserve clean power to drive the loudspeaker. So for your particular application you would be looking for a 25-35 watt loudspeaker as a replacement.

Hope this helps

Happy Trails

Cynical One

[evgdboy]

thanks, that's the type info i was looking for.
yeah it would have been a good deal price wise but i guess i'll just get something new in a lower wattage as you suggest.

thanks

[gitpiddler]

Well spoken as usual, o most cyn1 peaces, gitpid

[rumblefuzz]

I don't know if this will help you in any way:

I had the same experience as you with the stock speakers in my Music Man 212 HD 130 combo. I actually thought they sounded useless...
I got good results replacing the stock speakers with 2 vintage Fanes from a hiwatt-esque cab. The power rating of the 'hiwatt' was roughly the same as the musicman's (100w vs 130w).
My line of thought was that a hiwatt and a music man are in a sense similar amps, in that they're both meant to sound really clean, so the stock speakers must be meant for that as well. Hiwatt's more on the marshall side where the MM's more blackface-like, but from the speaker's point of view I guess I was right somehow.

I really don't think putting in vintage 30's would work...

[andy]

The generally accepted rule of thumb is around twice the amplifier wattage to the speaker wattage.

I hate to confuse matters, but I though it was the other way 'round- the wattage of an amp is rated on consistent output, so is therefore peaking at more than that. A 50w amp could be pushing 75w at its loudest points. Putting that through a 25w speaker may very well blow it.

I have been under the impression that an exact match in power is the minimum speaker wattage for safe use, any more than that just makes the speaker less likely to get blown by all the push from the amp, the only downside being that if the speaker is rated far, far above the amp, it may not be quite so lively sounding. For a really clean sound, that would not be such an issue anyway.

[newey]

Well, an "appeal to authority" (ipse dixit, in Latin) is one of the logical fallacies in formal syllogistic logic. But I'll trot out Steve Carr of Carr Amps, who indicates in this interview that he prefers to use 60-70 watt rated speakers with his 8-watt Mercury tube amp.

[evgdboy]

ok now i'm totally confused....lol

[cynical1]

evgdboy -

There is a lot of conventional wisdom out there. I've been using this particular piece of wisdom for 30 years and haven't blow a speaker yet.

As long as you stop turning up the amp when it starts to clip you're probably going to be fine. I looked up the specs on the loudspeaker in question:

Red White & Blues
Size: 12"
Power Rating: 120W RMS
Frequency Response: 70-4.5kHz
Sensitivity: 101db
Impedance: 8 ohms
Voice Coil: 1.75" edge wound
Magnet Weight: 38 oz.

The sensitivity of 101db means your 50 watt amp will drive it. The 38 oz. magnet is a heavy weight and will make your amp work a bit to drive it. Loudspeakers are notoriously inefficient and waste a good deal of the power your amp puts out to drive them. This is where the problem of clipping comes in when you under power the loudspeaker

Matching your ohms is more important, but it sounds like you've got that covered.

Considering this is a $75.00 speaker, base your decision to use it on how good the deal is. This speaker will not give you any more volume, so watch your levels and you'll get more life out of it.

Ain't it fun asking "rule of thumb" questions...

Happy Trails

Cynical One

[JohnH]

Interesting - Ive also heard that piece of advice wrt having big power amps to drive speakers foe PA applications, so you never clip the amp. Power amp clipping in a solid state amp effectively connects the speakers to the power rails (bad). Accepted.

But, if its a tube amp, you want speakers to be about 2x the rating of the amp, so you can drive the amp hard and have the speakers take it.

And, all commercially available combos (that I know of), whether SS or Tube have speakers rated higher than the amp wattage.

John

[evgdboy]

here's a lil update on this...
my bud let me hook up that red white & blues speaker to my amp to check it out. it sounded real good but too loud (i must be gettin old)
my usual stage vol. is at about 4-5...the rw&b had the same vol at about 1-2.

i figured out that the musicman rd50 originally came with a 75w speaker.
i ended up getting a eminence tonespotter 75w...it sounds great.
i didn't want a big increase in vol. just better tone.