2 Soundscraftsmen amps - 2 acoustat speakers

kerneljacksom

I have searched the site but I don’t seem to find exactly what I am looking for.

I need to know how to hook up 1 amp per speaker. I have a Soundcraftsman MA5002 Power Amp, that I bought brand new way back in the day, running off of an AudioSource Preamp Two. I recently acquired another Soundcraftsman MA5002.

I acquired a pair of Acoustat speakers and they sound quite nice but, even with the power of the amp my volume is not as loud as I would like.

What I want to do is have one amp run the left channel and the other the right.

marvda1

can the amps be set to mono?

kerneljacksom

This I cannot answer that at this time. I have the manual somewhere but I need to find it. I have not received the one I recently purchased. Let's assume for the sake of argument that they are just straight forward amps with no general provisions for mono.

marvda1

are the acoustats bi-wire capable?

kerneljacksom

I am sorry to say that I don't know that either. They are vintage speakers and I didn't get the manual with them but I will try to find out
Thanks

kerneljacksom

I am sorry to say that I don't know that either. They are vintage electrotatic speakers and I didn't get the manual with them but I will try to find out
Thanks

marvda1

if you have the speakers on hand, check to see if each speaker has one pair or two pair of terminals.

kerneljacksom

just 1 set of terminals on speakers

kerneljacksom

Just 1 set of terminals

kerneljacksom

sorry about the double posts, I thought i was deliting them. Need to get used to this forumThanks

marvda1

with the one set of terminals you can only use both amps if they can be run as monoblock amps.

kerneljacksom

My preamp has 2 sets of Line outs and I had used the one Soundcraftmen on one set and the other line out with another amp. Each was controlling its own set or speakers though.

Is there a way I can series the out puts of the Amps to make each control just one speaker

Polkersince85

There are two versions of the Ma5002. The MA5002 and the MA5002A. I don't think they are bridgeable. The MA5002A is 2ohm stable continuous. The MA5002 puts out 375 at 4ohms 2ch driven. That should be enough volume for anybody. Both are built for a ballistic rating. You can get music out of a fork laid across the terminals.

marvda1

not that i know of unless you can get someone to mod the amps.
marvin

kerneljacksom

I used to have a pair of Infinity Quantum 2’s hooked up to it and they were pretty inefficient speakers but I did get some sound out of them. They have since fallen in need of repair and I think I know of a place that I can take them to.

With the Acoustat’s the amp will turn the green clipping lights on and with some transients will hit the red overload light and the you better make sure you turn the pre amp down before it resets. Tha may be te reason the Infinitys got sick. In those days there were no remote controled preamps and if you were in the middle of something, those speakers were gonna take a hit as well. The specs on the damm thing are outrageous.

Maybe I need to get rid of the Acoustats and fix the Infinitys and get another set of speakers and run one amp for front and one for rear and set them up side by side. The Acoustats are very dirictional and you need to be in the sweet spot to get the most of them, but when you are there, man are you there.

I have had other speakers set up with them and had the neighbors begging me to stop. Those days are behind me but once in a while I like to let it blast.

I have always wanted to get another of those amps and I guess I should have looked into doing this bridge set up before I bought it. In any case it is a kick **** amp and will figure out something for them. I don’t know as to whether or not I want to modify them or what it would take to do it.

These amps are the ones with the VU meters. I am looking at the owner’s manual right now and see no mention of A. I don’t want to go behind the thing right now to see but there is no A the front of the Amp.

The spec sheet says Power output is 250watts RMS-8ohms/360 watts 4ohns (per channel) It also states
I.M. Distortation - Less thab 0.05%
T.H.D. - Distortation Less than 0.02%
Signal to Noise -Greater than 105dB
Frequency Response +- 1/4dB 20Hz to 20 KHz
Slew Rate - Greater than 90v per micro-second (supply)
Slew Rate - Greater than 50v per micro-second (amplifer)
Damping factor - Greater than 100
Stability - Any load 2 ohms to 32 ohms
Input Sensitivity - 1.28 RMS for rated output
Imput Impeadence - 15 ohms to 50k ohms

mike22

If you have done that--got rid of the acoustats--and the amp is excess now--do you want to sell it??

Just a thought.

Mike mb2222@aol.com

kerneljacksom

I lost interest in that project however during the time I Picked up A Rotel preamp.

I now would sell one Soundcraftsmen amp, the Rotel preamp, & the Acoustat speakers. All are in perfect working condition.

I am also willing to sell the Quantum 2’s. They need to be rebuilt, but cosmetically they are perfect, including original grills. If interested in any items I can send pictures.

reeltrouble1

we should have a newb only FM. once you go past 25 you cant see it and all your posts their disappear.

RT1

steveinaz

You need the Soundcraftsmen "AB-1" bridging adapter...

kerneljacksom

Where on earth would I find such an animal, or how would I go about building one?

steveinaz

Ebay or audiogon, they are not made anymore....Basically both amps connect to it, your preamp--then it plugs into the wall; then you use both + terminals on each amp to each speaker. When I ran 2 Soundcraftsmen PM840's w/the AB-1, I got 600 watts/rms @ 8ohms---1200 watts peak. The PM840 by itself in stereo put out 205 watts @ 8ohms.

I'm sure some DIY'er sites would have instructions on building a bridger--there wasn't much to it.