Peavey Vypyr 15 upgrade

[baggy]

Great site!! I have learnt a lot from you folks already and look forward to delving into the wonderful world of modding etc with the info found here.
My questions are......
I have a Peavey Vypyr which is a great little amp but is lacking in the quality of speaker, any suggestions on a replacement speaker, (original is 25 watts and 3 ohms), and something that isn't going to cost more than the amp originally did ($99.00).
I am a woodworker and was also thinking of building it a new cabinet out of purpleheart with maple and black walnut trim and maybe some router work to dress it up a lil more, any thoughts on this idea.
Also can I change cabinet size a bit to accomodate a 10" instead of stock 8"
Look forward to hearing your thoughts from all you "Gods"

Cheers

[newey]

Baggy-

Hello and welcome!

I don't have any experience with the Vyper series of amps but most folks seem to speak highly of the stock Peavey speakers in their amps, as compared to some other brands. The Peavey Black Widow speakers seem to be highly regarded. Is this what you have?

Also can I change cabinet size a bit to accomodate a 10" instead of stock 8"

Certainly you can, since you're talking about a complete cabinet rebuild. The impedance must, of course, match, but other than that your speaker choices are wide open. Putting a 10" in there as opposed to an 8" would probably hugely benefit the tone regardless of the particular brand of speaker you choose. I've never heard an 8" guitar speaker than I thought positively about, 10" would be my minimum unless we're talking a micro-sized travel/portable amp.

(original is 25 watts and 3 ohms)

Are you sure it's 3Ω? I've never heard of an odd-numbered impedance rating on a speaker. If, in fact, it's a 3Ω, you're going to have a hard time finding a direct replacement, as I'm unaware of any. Doesn't mean they don't exist, but they certainly aren't common.

[baggy]

Thank you for your reply and thoughts Newey, MUCHLY appreciated!!
Just did a double check on speakers Ohm rating and sure nuff it's 3 ohms, never heard of that myself either, (usually 4,6,8 ohms). I may be stuck with it if Peavey says it has to be 3 ohms otherwise I could fry circuitry. Obvously I am not worried about the warranty as its $99 not $990
Sent an email to peavey product development dept a week ago and still no reply, so resent to sales and hopeing to get a response on a better quality speaker, (I can't expect them to put a poundable and clean tone speaker into a $99 amp). Also I do hear the speaker starting to crap out at mid volume, which tells me it's easily been over powered.
Would a $60 10" Jensen outdo this stock unit?
The rest of the amp I am very happy with and do highly recommend it as a home practice amp

[newey]

Just did a double check on speakers Ohm rating and sure nuff it's 3 ohms

Hmmm. As I understand these amps, this is a straight solid state amp, not some sort of hybrid. correct? IOW, Peavey's "Patented TransTube Technology" doesn't involve any actual, errr, tubes, right?

With a solid state amp you should be able to use a 4Ω speaker with no problems. So long as the amp "sees" a higher impedance load than its rating, you're okay. Tubes require a closer match, but it still can be a bit off, 4&Omega would probably be close enough for a tube amp also.

EDIT: I replaced the stock Fender 10" in my Frontman 25 with a Jensen Mod 10-35 and I like it a lot better than the stock Fender. That doesn't tell you much for your setup, though. But that was only a $40 Jensen in a $130 amp, and it made a big difference for the better, FWIW.

[ChrisK]

A speaker with a 4 Ohm impedance rating will often measure less (such as 3 Ohms) resistance (which is just one component of the impedance along with inductive and capacitive reactance).

For instance, for 8 Ohm speakers;
www.allenamps.com/Eminence/lilbuddy.php

www.allenamps.com/Eminence/copperhead.php

www.allenamps.com/Eminence/ragincajun.php

[sumgai]

baggy,

Welcome to the NutzHouse! ;D

Many models of Polytone amplifiers have also used speakers rated at 3Ω, so your unit is not the only one to "go down a different path". Searching for a speaker for one of these amps might bring you more positive results, who knows.

But if all else fails, you can just as easily use a 4Ω unit, of any physical size. This won't affect the amp's longevity, and I'm fairly confident that the tone will also improve to a level that you'll kick yourself for not doing it sooner. ;D

HTH




sumgai

[baggy]

hey guys, thanks for all your thoughts and ideas. I'm sure this amp will be modded soon to a better speaker. Will post a pic of new hardwood case once it's built, (could be a few months, too many other projects on the go).
The amp is a solid state unit Newey.
Thanks for the links ChrisK, will check em out next
Nice to be welcomed to the nut house Sumgai, I should fit right in, (straight jacket is optic orange with purple micro dots tho, so hope that doesn't send anyone over the edge).
Cheers n beers all

[baggy]

Thanks for the links Chrisk, unfortunately I'm up in da' great white north and found that shipping, duties and brokerage fees end up doubling the price of anything I buy from the US of A. So much for "free trade"!
Any recommendations for a Canuck supplier of speakers, and any models in particular for this amp, (I play classic rock), preferrably in BC or Alberta??

[ChrisK]

I don't know, get on the google and run the internets (or sumpthin').

[mathiasx]

Actually my Vypyr 15 is way too loud. Would it be alright if I put two 10" 4 ohm speakers in parallel if it would only sacrifice some volume? Or am I way off base here and it would cause other complications?

[sumgai]

mathias,

In order to reduce the volume, you want to connect those two speakers in series. This creates more load to the amplifier (tube or solid-state) and thus it delivers less power to said speaker(s). A parallel connection would decrease the load, thus allowing the amp to deliver more power, which goes against what you asked for.

Worse, using two 4Ω speakers in parallel would mean 2Ω total impedance, and there are almight few amps that can handle that kind of power output without blowing themselves up. Two 4Ω speakers in series gives you 8Ω, and that will work for just about any guitar, bass or PA amp you're likely to find.

HTH



sumgai

[mathiasx]

Good thing you straightened me out. I might have blown something up! Two ten inch speakers in series! Got it. Thanks!

Which begs another question, just any old 10" 4 ohm speakers will do so long as the impedence matches as previously mentioned? Or do amplifiers require a more robust speaker?

[newey]

Which begs another question, just any old 10" 4 ohm speakers will do so long as the impedence matches as previously mentioned? Or do amplifiers require a more robust speaker?

Depends on what you mean by "just any old" and by "will do".

There are a ton of variables in speaker design, and impedance is only one of them. A speaker's dynamic range, its efficiency- you'll find as many opinions of these factors as there are speakers.

In general, speakers designed for home audio use are a poor choice for guitar amplification. They're not built for abuse, and will likely sound "sterile" anyway, as they are designed to faithfully reproduce a full spectrum of sound.

Bass, PA, and Keyboard speakers are all "full-range" speakers, and may also sound sterile and "cold", although they'll certainly stand up to a guitar amp just fine.

Speakers specifically designed for guitars are designed to reproduce a limited frequency range, and to reproduce it somewhat imprecisely, to provide what folks call "warmth" or "coloration". All of which is highly subjective. Lots of guitarists use bass speakers and swear by them. And lots of folks play through PAs using full-range speakers without complaint, although often the signal is first run through a guitar amp, real or sim.

So, within certain parameters, "any old" speaker can be used, and they "will do", if "will do" means "produces sound". Once we get into what kind of sound they produce, well, now we're off into the territory of personal preferences.

[sumgai]

mathias,

Robustness is a matter of degree. If you want to use two 100 speakers for your 25 watt amp, that's fine. (Whereas one such speaker would be work in terms of handling power, but you may be connecting two of them to get a closer impedance match.... nothing wrong with that.) However, if you want to use 25 watt speakers for your 100 watt amp, then you'll need more than two of them, like four of them at the least.


Short story long:
One has to coordinate both power and impedance - they depend on each other. Getting it right means good tone and long-lasting equipment. Getting it slightly wrong is usually OK, getting it drastically wrong is cause for ejection from the NutzHouse.

Power always divides equally, given speakers of the same impedance. This means, for example, that two 50 speakers can handle 100 watts, no matter if they are connected in series or parallel. However, if the impedances are not the same, then you can simplify everything by saying "more power will go to the one with the lower (lowest) impedance". The exact math is easy - it's a ratio of one to the other. (Where more than two speakers are involved, we'll cover that below.) So for instance if I have an 8Ω speaker and a 16Ω speaker, the first is half the impedance of the other, so it will get 2/3rds of the total power, and the higher impedance unit will receive the remaining 1/3 of the power. (I'm leaving out a couple of steps in my "proof", I think that they're obvious. But if not, just ask, and I'll "fill in the blanks".)

Now, impedance is the other side of that coin. If you have a single speaker of 8Ω, then the power delivered to it will be all that the amp can deliver. But if you connect another 8Ω speaker in parallel with the first one, then the amp will attempt (successfully or not) to deliver about twice the power. Why? Because the load was cut in half, from 8Ω to 4Ω.

The same thing occurs going the other way, when we use series connections. Two 8Ω speakers in series will give us 16Ω, and that presents less load to the amp, so it needs to deliver less power than before. Again, about half. (Half, double, it's all relative, and in fact it's never exact, but it's close enough for most discussions of this nature.)

Unfortunately for us bone-headed math-types, the calculations for impedance connections are not straightforward. So, instead of memorizing each of these formulas, may I suggest that you bookmark this page, and label that bookmark as "Speaker impedance calcs" or somesuch. (No vanity here, I assure you. )

For parallel impedances, two equal values divide in half. Three equal values divide in thirds, four equal values divide in quarters, and so on. For unequal values, the formula is:

1/(1/x + 1/y + (as many speakers as needed)) (you saw newey give this, up above)

Let me illustrate with an example. Take a 16Ω speaker and an 8Ω speaker and put them in parallel. The math goes like this:

1/16 = 0.0625

1/8 = 0.125

0.125 + 0.0625 = 0.1875

1/0.1875 = 5.3333~

(Easy to do with most any calculator.)

Note two things here: The answer is always less than the lowest ohmage speaker, and that you almost never end up with an exact value. But for the most part, you'd hook it up to the closest value your amp can handle, in this case that would be the 4Ω tap. Everything would sound and work fine, but as per the above paragraphs, more of the sound will be coming out of the 8Ω speaker.

Now in series, everything adds nicely, just like in simple arithmetic. Doesn't matter if the speakers are the same impedance or not, just add them together.

And finally, we can combine the two connection methods. Commonly, you'll find four 8Ω speakers in a cabinet rated for..... 8Ω. That happens because we take two of the four units and put them in parallel, which gives us 4Ω, right? And we do that again with the remaining two speakers. Now, we can take one 4Ω pair, and place it in series with the other 4Ω pair, and voila!, we get 8Ω. Otherwise, we'd get 2Ω (all in parallel) or 32Ω (all in series) or some odd number in between. (3 and 1 or 1 and 3 - you do the math. )


OK, that about ends the lesson. Any questions, you know where to ask, eh? ;D

HTH




sumgai

_{(Edited by newey to fix link)}