Phoenix Gold Phorum

Hello Audiophiles,

I own one PG M50 and two M25s for the past approx 20 years (bought new). They are all operating just fine (as far as I can tell).
I used to run two JL 12W0V2 but those got old and blown. Then back in 2006'ish I ran some new 12W0V3 or somthing like that, those are now messed up due to sitting in the garage for the past few years. I haven't been running any subs due to weekend racing my daily driver.


I need advice on what specs of sub to shop for using my M50?
here are some specs that I found on the net about my amp:

M50 specs
==========
Into 4 ohms @ 12.5/14.4 VDC
50/85 WRMS x 2
Into 2 ohms @ 14.4 VDC
120 WRMS x 2
Bridged into 4 ohms @ 14.4 VDC
245 WRMS x 1

I'm shopping for two 12"s and want to spend around $100 each, will be used in a sealed enclosure.
I need advise on what specs of sub to shop for using my M50?
Any help would be greatly appreciated.

Thanks

Anything with a 4 ohm load...

the M50 can handle 2 ohm mono, but after 15min it will start to cook so you're better of with 4ohm.

witch brand is more you're personal taste......

but for two 12's the M50 will not be powerful enough..... just use one.......why not in a vented enclosure....

zeropoint0.5 wrote:Anything with a 4 ohm load...

the M50 can handle 2 ohm mono, but after 15min it will start to cook so you're better of with 4ohm.

witch brand is more you're personal taste......

but for two 12's the M50 will not be powerful enough..... just use one.......why not in a vented enclosure....

So anything 4ohm
I'm want to run two in a sealed box because I already have the box

Kirghiz wrote:http://www.phoenixgold.com/products/sub ... oductID=15

I like that, I'm calling a local dealer but their phone is busy

I have a couple more specific questions:
So what kind of Watt range should I shop for? (I was thinking 200-400 RMS?)
What happens when you get a larger watt sub (1000 watt RMS) on a small amp like I have?
What about single vs. dual voice coil? ( I was thinking dual?)

I would look for something about 200 watts rms or so for a pair, or no more than 400 watts rms for a single. The M50 isn't a lot of power. It isn't really even a lot of power for a single sub in today's world of subwoofers.

If you went with a 1000 watt sub you would destroy it from not enough power before you even get it home if you pushed it because you'd clip the amp.

If you are looking for a pair of subs, you are going to need a dual 4 ohm sub or a single 2 ohm sub, because single 8 ohm subs are few and far between anymore. The most common would be the dual 4 ohm variety. The only effect it has is it gives you wiring options, and since you need to reach a four ohm load total for the pair for that M50, those are your choices.

But.....another option would be to use your M50 to power a set of components, and pick up a cheap Class D mono block amplifier to drive the subs. I saw a Phoenix Gold SD1300.1 on Ebay last night for $250, which would give you a lot of subwoofer options.

hmmm, choices...


Thanks for the advice

yes it would be smarter to use the m50 for speakers along with both m25's and buy

a heavier (class D) amp to feed the subwoofers.....

depends on you're expectations and budget of course.....

buying subs for an existing box is not that smart...better building an exact box for the subs you will buy......

or try to find the simular oldskools the box was build for somewhere second hand........

good luck with it......

Another thing to consider. These are wonderful sounding, beautifully made legendary old school amps and they require a little bit of extra care compared to new amps. Many old PG amps including M-series have leaky power supply caps. If you don't have them changed you run the risk of the amps setting on fire. M50 has 3 and M25 2 of these leaky 16V 2200uF caps in the power supply section.

Changing them is a small job if you know what you are doing. If you don't, you might harm the amps.

A Jbl gti 1200, or a gti 1000 would match up good to this.

Theoretically caculated spl:
gti 1200 93db/w/m @0.5m (1 3/4 cu,ft recommended)
M50 - 1x250w(ish) bridge mode
=123dB spl

I agree with Mr. Wild... if you want those amps to continue working for another 20 years, you need to replace the capacitors NOW. The good news is the M series is VERY easy to do, if you have even basic soldering skills. If not, it should still be very cheap to have done by a professional. It's not a question of if the capacitors will fail, but when... and when they do, they short out the power supply section, and generally start a small fire, consuming several inches of the circuit board (if not your whole car!!).

An M50 on your subs is going to be just fine, as long as you find efficient lower power speakers. You won't set any output records, but if you want it to blend with your front stage you don't want considerably more power anyways. My ideal audiophile choice would probably be something like a pair of IDQ 12 v2's, with dual 4 ohm voicecoils, which are no longer made (the new V3's are ok as well, but not as efficient). The PG R series is also a fantastic choice... and they are new, and much better looking.

Mr. Wild wrote:Another thing to consider. These are wonderful sounding, beautifully made legendary old school amps and they require a little bit of extra care compared to new amps. Many old PG amps including M-series have leaky power supply caps. If you don't have them changed you run the risk of the amps setting on fire. M50 has 3 and M25 2 of these leaky 16V 2200uF caps in the power supply section.

Changing them is a small job if you know what you are doing. If you don't, you might harm the amps.

X2

changing the caps is a must , but the question was of course about the sub choice so i just responded that question.....

I just bought 4 10" jl audio wxv2 for $160 cnd today to run off my 460watt rms at 4ohm so there are alot of deal be had if you look

I second that idea about using a JBL 1200GTI sub. Very efficient and good sounding old school sub! Only problem is finding them, especially in good condition.

I have one in my car in a 1 3/4 cu ft ported box with a MS-275 feeding it. It sounds totally awesome with rock and heavy metal. Gets stupid loud too, considering the limited power I have. Loud like when you speak and your voice warbles and gurgles!

Or Celestion AP or AD, they have canvas surround just like the gti. Should make a SQ ruckus

I like the Image Dynamics. I was thinking the same thing about the box. Purchasing one woofer may be a simple solution afterall. I can easily build myself a box to spec for a single woofer. So I'll keep shopping.

More about the amps:

stipud wrote:I agree with Mr. Wild... if you want those amps to continue working for another 20 years, you need to replace the capacitors NOW. The good news is the M series is VERY easy to do, if you have even basic soldering skills. If not, it should still be very cheap to have done by a professional. It's not a question of if the capacitors will fail, but when... and when they do, they short out the power supply section, and generally start a small fire, consuming several inches of the circuit board (if not your whole car!!).

An M50 on your subs is going to be just fine, as long as you find efficient lower power speakers. You won't set any output records, but if you want it to blend with your front stage you don't want considerably more power anyways. My ideal audiophile choice would probably be something like a pair of IDQ 12 v2's, with dual 4 ohm voicecoils, which are no longer made (the new V3's are ok as well, but not as efficient). The PG R series is also a fantastic choice... and they are new, and much better looking.

Mr. Wild wrote:Another thing to consider. These are wonderful sounding, beautifully made legendary old school amps and they require a little bit of extra care compared to new amps. Many old PG amps including M-series have leaky power supply caps. If you don't have them changed you run the risk of the amps setting on fire. M50 has 3 and M25 2 of these leaky 16V 2200uF caps in the power supply section.

Changing them is a small job if you know what you are doing. If you don't, you might harm the amps.

Excellent advice! I will change the caps since I haven't ran the amps in a few years, but I would like them to burn my car down

Can you point me in the direction of purchasing the needed caps?
What are the specs, (16V 2200uF) ? Is there a need to get upgraded ones?
Where can they be purchased at, Radio Shack?

Thanks,

http://soundbuggy.com/Eric/Car%20Audio/ ... index.html

It's a good idea to increase the capacitance value, just make sure the height, width, voltage and temperature rating are the same:
http://search.digikey.com/scripts/DkSea ... 93-1543-ND
http://search.digikey.com/scripts/DkSea ... =P11210-ND

stipud wrote:http://soundbuggy.com/Eric/Car%20Audio/ ... index.html

It's a good idea to increase the capacitance value, just make sure the height, width, voltage and temperature rating are the same:
http://search.digikey.com/scripts/DkSea ... 93-1543-ND
http://search.digikey.com/scripts/DkSea ... =P11210-ND

Awesome! Thanks


I will do definitely do the caps, too easy of an insurance to not to.