Stereo-Mono Operation

[DJGTSR 10+ year member]

Hey,

I have 3 10W7s, I want to hook it up so I have one on each channel and the other bridged on both channels.

What would the overall impedance be on the amp and what would the woofers see? Would they be equal in the power they recieve?

J

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[skadude016 5,000+ posts]

wait so this is a 4 channel amp? You are giving one of those w7's a shit loud more power than the other two. are these the SVC w7's or DVC?

 

[djman37 5,000+ posts]

right off the bat it doesn't sound like a good idea...it's a stereo amp? What can the amp run a final load at? Are the W7's D6?

 

[DJGTSR 10+ year member]

2 channel amp.

1 10W7 on right

1 10W7 on left

1 10W7 bridged on both channels.

I need to know the resultant impedances to make sure my amp can handle it before I hook it up.

I also need to know the proportional power that the subs get.

J

 

[DJGTSR 10+ year member]

W7s are SVC. The amp is a USA-400 (22 incher from usamps). It can handle this sort of operation, Ive read in the manual //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

Im just confused on how to calculate impedance loads for Stereo-Mono...

J

 

[DJGTSR 10+ year member]

W7s are SVC 3 ohms.

J

 

[djman37 5,000+ posts]

amp specs

USA-400 Only

One Ohm Stable

50 Watts x 2 into 4 Ohms

66 Watts x 2 into 3 Ohms

100 Watts x 2 into 2 Ohms

200 Watts x 2 into 1 Ohms

200 Watts Bridged into 4 Ohms

264 Watts Bridged into 3 Ohms

400 Watts Bridged into 2 Ohms

 

[DJGTSR 10+ year member]

Not that amp bro, the old school USA-400.

J

 

[djman37 5,000+ posts]

amp specsUSA-400 Only

One Ohm Stable

50 Watts x 2 into 4 Ohms

66 Watts x 2 into 3 Ohms

100 Watts x 2 into 2 Ohms

200 Watts x 2 into 1 Ohms

200 Watts Bridged into 4 Ohms

264 Watts Bridged into 3 Ohms

400 Watts Bridged into 2 Ohms

hook 3 3ohm SVC subs together in parallel for a 1 ohm load.

 

[djman37 5,000+ posts]

Not that amp bro, the old school USA-400.
J

well, the lowest ohm load you can give that old skooler is 1 ohm

 

[DJGTSR 10+ year member]

The amp is not stable in 1 ohms bridged. Actually the amp im getting is an X series, so its actually only 2 ohm stable per channel.

Ill be back in a bit to discuss, i need to figure this out but i have class now,

J

 

[djman37 5,000+ posts]

okay, not so old school specs

Two Ohm Stable

100 Watts x 2 into 4 Ohms

132 Watts x 2 into 3 Ohms

200 Watts x 2 into 2 Ohms

400 Watts Bridged into 4 Ohms

i dunno, i can't come up with a decent scheme. If the manual says you can do it, then I guess you're good....that's with 3 ohm loads???//content.invisioncic.com/y282845/emoticons/crap.gif.7f4dd41e3e9b23fbd170a1ee6f65cecc.gif

 

[DJGTSR 10+ year member]

okay, not so old school specsTwo Ohm Stable

100 Watts x 2 into 4 Ohms

132 Watts x 2 into 3 Ohms

200 Watts x 2 into 2 Ohms

400 Watts Bridged into 4 Ohms

i dunno, i can't come up with a decent scheme. If the manual says you can do it, then I guess you're good....that's with 3 ohm loads???//content.invisioncic.com/y282845/emoticons/crap.gif.7f4dd41e3e9b23fbd170a1ee6f65cecc.gif

Old school specs on the USA-400 ( 1 ohm stable ) are:

200 X 2 at 4ohm

400 X 2 at 2ohms

400 bridged into 8 ohms

800 bridged into 4 ohms.

Im hoping that for the USA 400X the specs get bumped up to 400X2 at four ohms.

J

 

[DJGTSR 10+ year member]

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=5867854136&rd=1&sspagename=STRK%3AMEWA%3AIT&rd=1

This is the amp that will be bumping the W7s.

 

[helotaxi 5,000+ posts]

In theory, you would be running 1 ohm per channel final load (same as bridged @ 2 ohm). The left and right subs would be getting a paltry 267 watts each and the center would be getting 1067W. Result will be a ton of cancellation and a crappy sound. That is WAY the wrong amp for 3 of those subs. You would probably get better sound from just one sub on that amp than the 3 wired as you propose if you are dead set on that amp. If the amp is not a done deal and you have the subs, find a better amp for the job, preferrably one that can handle a 1 ohm mono load and put out a good amount of power.

And IIRC the difference between the 400 and the 400X is a built in crossover not more power.