T-amp compatability w/ sub plate amp

[Jim Shearer]

OK, please forgive me if I ask a question that you have answered a thousand times, but I can't seem to locate what I want to know w/ the search function. And I don't know enough about electronics to figure it out myself.

I understand that you can't hook up a Sonic Impact t-amp to a subwoofer plate amp via speaker wires due to the lack of a common ground in the t-amp.

I can see that the neg speaker leads should not be connected, as in hooking up both channels to a plate amp. However, is there a problem w/ connecting only ONE channel to the plate amp by speaker wire? Is the 'floating ground(?)' of the t-amp output not compatible w/ the (I assume) grounded input of the plate amp?

Thanks for your help (and patience.)
Jim

[pacificblue]

The Sonic Impact is a bridged amplifier. That means all speaker terminals are 'hot' and connecting either of them to ground would be a short-circuit.

You could use RCA-Y-adapters and split the input signal before the T-Amp.

[Jim Shearer]

Very interesting! I guess if I want to use a T-amp, I will need to build a passive pre-amp.

Thanks much for the info!

Jim

[Nuuk]

Is the plate amp class-D? If it is AB you probably won't get very good results.

[amt]

You can build a "magicBox" for next to nothing and see what you think.
I built one and is seems to work okay.

http://www.audiocircle.com/circles/i...&topic=38384.0

Audiomagus sells something similar but more sophisticated if you dont want to build one. Maybe Panomanic will pop in to 'splain the performance difference.

http://www.audio-magus.com/SubLine_S...tor_p/slv2.htm


amt

[Jim Shearer]

amt,

Thanks! I don't think I want to spend as much for an interface to the sub amp as I spend on the T-amp, but the Magic Box looks easy enough.



Nuuk,

I'm unclear on what you mean. I've used a passive sub in the past, but have found using a plate amp much better--easy to integrate w/ the mains. And I only want the subs to go up to about 40 Hz. Can't say that the cheap class D amps have any audible issues below 50 Hz.

Cheers, Jim

[Nuuk]

It's the issue with class-T Jim where phase changes with frequency. This can make it had to integrate a class-T with a class-AB amp used in the same system.

I have both AB and class-T amps that I can use for my woofers but if I mix either of them with another class of amp, it just doesn't sound 'right'! (I cross over at 60 hz)

[Jim Shearer]

Interesting. Thanks for the advice.

Jim

[gurley123]

Sorry to dig up an old thread but does anybody have a copy of Ed's "Magic Box" diagram? The forum it was in is shut down and I forgot the particulars of it. Any help would be appreciated.