Sonic Impact Power Supply-Newbie

[ReallyBigWoofer]

Hello All,

Firstly, in the immortal words of Bugs Bunny,"What a Maroon", that me when it comes to electronics...

I have Altec Lansing Voice of the Theaters for Loudspeakers, and my intension is to Bi-Amp. I have purchased 2 Sonic Impact T-Amps. I have listened to one amp using my laptop as source and i loved the music (using batteries)!!! except for the lack of bass.

I have read all the reviews and these amps are for real!!!

I hope that you will assist me in my quest.

Question: the electronics store arround the corner has Tripplite Power Supplies, are these any good? The sales guy told me i can make them 13.8 Volt by twisting a pot inside and he has a 3 amp version, 4.5 amp version, and 7 amp version. I am thinking about 2 of the 3 amp versions. So agian, are the Tripplite power supplies any good for powering my Sonic Impact T-Amps?

Thanks.

[phn]

It's most likely very good. And expensive and total overkill.

You need two switching power adapters, 12VDC, 2.5A, type this: http://www.si5.com/products.php?pID=4011

Or you could build a linear PSU, one using a 30-50VA trafo, or two using smaller trafos.

13.8V will fry the SI. 12V is enough.

[ReallyBigWoofer]

Most of the reviews i have read state that the power supply is very important. I want to do a lot of tweaking as i go so that i can educate myself, just for fun. I am fearful of high voltage, so i wanted to purchase a power supply that would sound good and will not have any trouble with. I have not seen a review where they used a Tripplite Power Supply so i was just wondering if they were bad sonically.

As far as the 13.8 V, I am speaking from the 6moons audio review. I do know that this should be the absolute max.

Thank you for your time.

[Cal Weldon]

Hi RBW,

Judging by your handle, I think we'll get on fine.

What VOT's are you trying to push?

[Buckapound]

Consensus sems to be that that type of switching power supply is about as good as it gets for the t-amps. Two amps seems to be plenty. More than 4-5 and you're in fantasyland. The real money in terms of performance is doing the modifications to improve bass, etc.

I've had the SI runing at 13.8v no problem, although at that voltage a small heat sink is in order--the ones sold for computer memory chips fit perfectly. I've had them thermally shut down at 14.1v, so I know that's definitely over the limit.

Many PSs have a trim resistor that allow you to adjust the voltage. I set mine at 13.2v and it runs great.

--Buckapound

[phn]

I trust the Tripath datasheet more than I trust 6moons. It says maximum operating voltage is 13.2V. Higher can be used. But for how long? You don't need more than 12V. That's what I use to drive my Altecs.

[ReallyBigWoofer]

Cal: My Altec are A7-8G (515-8G in 828 Cabinets, 902-8B on 511B Horns with 8500 x-overs). The 828 Cabinet are made by me using 3/4 mdf then made pretty by surrounding them with 3/4 oak plywood with the horn section made from cnc cut profiles of mdf layed one on top of each other then covered with 3 sheets of 1/8" masonite to dress up the curve section. The 6 watts from the T-Amp will take them louder than my ears can take.

Buck: O.K., are switching power supplies the type you would find in computers? I happen to have 4 sitting on my desk right now. ASTEC Model SA 145-3435, +12V / 4.2A, +5 / 18.0A, -5V .3A, 12V 0.3A. Can these be used?

[Cal Weldon]

Gee RBW,

I thought you said you have some big stuff. Just a couple of little A7's? 10 watts is often enough. Nice sounding job on the cabinets. Can you post pics somewhere? I don't wish to highjack any further.

Are you running extra bass units?

[phn]

This is what constitutes big around these parts.

[Cal Weldon]

I thought he might have something like this:

Oops, that's more jacking, sorry.