Another MS2250 question...

Pedi · Post by **Pedi** » Fri May 21, 2010 7:40 am

I noticed this text in the scanned litterature-section.

This review was written by Chris Lewis for Auto sound in 1995, as he tested the MS2250....

I quote his words here:

When I tested this 2x250 watt amp, I got 2x280 into four ohms and 2x505 into two ohms. While this meets spec, it did not match the performance data Larry sent down from the mountain. Communicating with Ben in engineering solved the problem. Two resistors were the wrong value, and once changed, the Phoenix was transformed, putting out 437 watts per channel in 4-ohm stereo mode, and 630 watts per channel in 2-ohm stereo.

Is this something common, or was this just a problem on THAT piece of amp only...

Anyone knows anything about this?

GX3 · Post by **GX3** » Fri May 21, 2010 7:59 am

This would be good to find out. Did it list the a mono load?

todd217 · Post by **todd217** » Fri May 21, 2010 8:18 am

1260 would be the mono if it does 630@2 ohms

Stryker · Post by **Stryker** » Fri May 21, 2010 10:40 am

I think Pedi is asking if the resistors were just mistakenly forgotten to be changed on the test 2250 or could this mistake have been made on some of the very first 2250's....
meaning some of the earliest 2250's that are in some mebers hands. hard to know unless you can test wattage output at home, or know which resistors to look for exactly.

marko · Post by **marko** » Fri May 21, 2010 11:18 am

i always wondered this too, one day i'll try one on my front end to see what they can do in stereo mode

Post by **Eric D** » Fri May 21, 2010 11:34 am

I know what resistors they are talking about (well, I am pretty sure that is). They are the zanier diode power supply regulation resistors. One of them for each supply. By changing the value of these, you change the rail voltage of the amplifier.

I don't believe 437W into 4 ohms though. The rail voltage required to get this output is not available with the stock transformers. This may have been a pre production sample or something and the transformer was wound for more.

When I modified my MS1000TA, I discovered what these resistors could do. I got about 320W or so with the PG stock resistor values. I then changed mine and got 380W, the most prior to running out of rail voltage.

I was measuring at 13.8V input, not 14.4V, so the amp would do more at 14.4V.

The MS1000TA which nicco owned (I think he sold it, but forgot who too) is the most powerful MS1000TA (or MS1000 for that matter) known.

nico boom · Post by **nico boom** » Fri May 21, 2010 6:06 pm

About the output of those amps; wanted to share the following. I had some bad nights thinking what to do with your ex Eric [amp for that matter] since I noticed that while testing it, there seemed to be coming virtually no end to it's clean output.
After not using it for more than 2 years I finally decided to sell to Carlos [pescador 17].
Hope he will post some pics or whatever of the amp in it's current situation.
I remember you pointed out those resistors and asked me for their value when Cecil claimed my BNIB MS1K had stock 63 Volt rails as well......and all the hassle it created.
After hooking them both up, it already became clear within 10 minutes that your modified amp produced more heat with both amps in idle, indicating a higher current-flow. I should have put the DMM with scope on both of them, but it never came to that.
If I knew that I was going to use it one day, I would never have sold the MS1000 FOSGATE EDITION.....

I just hope Carlos will take GOOD CARE of it.

pescador 17 · Post by **pescador 17** » Sun May 23, 2010 2:27 pm

nico boom wrote: If I knew that I was going to use it one day, I would never have sold the MS1000 FOSGATE EDITION..... I just hope Carlos will take GOOD CARE of it.

Hi, all posting a few pics of the amp Nico was posting about in its brand new home...

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str3atwarrior · Post by **str3atwarrior** » Sun May 23, 2010 2:34 pm

Wow i like the color!

Pedi · Post by **Pedi** » Sun May 23, 2010 3:00 pm

Impressive install...

What car is this mounted into, and what are the other amps? It is a real powerhouse, for sure !!!

Post by **stipud** » Sun May 23, 2010 3:13 pm

That's insane! How do you power that??

pescador 17 · Post by **pescador 17** » Sun May 23, 2010 3:26 pm

Pedi wrote:Impressive install...

What car is this mounted into, and what are the other amps? It is a real powerhouse, for sure !!!

Its installed in a CHEVY 3500 1997 7.4 LT Ill post all the details in a bit, don't have the time to do it all at the moment.

stipud wrote:That's insane! How do you power that??

Marty McFly: Are you telling me that this sucker is nuclear?
Dr. Emmett Brown: Hey, hey, hey. Keep rolling. Keep rolling, there.
[Marty raises the camcorder]
Dr. Emmett Brown: No, no, no, no, no. This sucker's electrical. But I need a nuclear reaction to generate the 1.21 gigawatts of electricity I need.

Hehe..

It feels like that at the moment, presently have 18 Deep Cycle Marine Batteries, and installing multiple Alternators at the moment.

nico boom · Post by **nico boom** » Mon May 24, 2010 8:49 am

I think the amp has got a good home for sure....

Beside some MS-familymembers, it sounds like it's got plenty to feed on.
Two things come to my mind; are all those amps recapped already?

, and do you have your install insured..... because it will get a lot of attention from both good, and bad people.
Just hope you'll be able to enjoy this for years to come!
Like Ivar said; IMPRESSIVE.

pescador 17 · Post by **pescador 17** » Mon May 24, 2010 2:40 pm

nico boom wrote:I think the amp has got a good home for sure.... Just hope you'll be able to enjoy this for years to come!
Like Ivar said; IMPRESSIVE.

Most of them have new caps, and she doesn't need insurance... She never goes out unescorted and she never leaves our sight.

She even sleeps in her own climate controlled home.

Here's a photo of her:

I plan on making a install post soon, just need to finish a few things.