3ohm Plate amp

[Sr SQ]

Does any one know of a plate style sub amp that wont hate life at 3ohms?
All the ones I have seen only rate down to 4ohms and I have a nice 15" woofer that has dual 6ohm coils that I would like to use in a DIY project.
The sub is rated at 600w rms so I would like a amp of at least 500w
TIA
-Sr

 

[mike c]

i've never seen a 3ohm rated plate amp.

will you consider a pro amp for a passive sub? Behringer EP2500 is stable to 2 ohms on each channel

i figure one channel should be between 600-800watts (because its 20hz output at 4ohms is 600w and 2ohms is 800w)

 

[Sr SQ]

i've never seen a 3ohm rated plate amp.

will you consider a pro amp for a passive sub? Behringer EP2500 is stable to 2 ohms on each channel

i figure one channel should be between 600-800watts (because its 20hz output at 4ohms is 600w and 2ohms is 800w)

Thanks for the reply.
I never gave them much thought but I guess it wouldn't be to hard to go that route either if I could find an amp for a fair price.
I will look into it a bit more.

 

[mike c]

im using a behringer EP2500 myself (on my passive DIY sub) ... plenty of power as tested by a 3rd party.

the Behringer leaves you open to:
-a second DIY sub (the other channel)
-more power (future use)
-stable to 2ohms means 3 ohms is easy
-stable to 2ohms also means it can be bridged to 4ohms of 1600 whopping watts

passive subs are easier to place in room too, just speaker wire to worry about ... active subs need power cords and coaxial cables. easier to EQ and crossover because the amp is close to the equipment rack.

 

[WmAx]

im using a behringer EP2500 myself (on my passive DIY sub) ... plenty of power as tested by a 3rd party.

the Behringer leaves you open to:
-a second DIY sub (the other channel)
-more power (future use)
-stable to 2ohms means 3 ohms is easy
-stable to 2ohms also means it can be bridged to 4ohms of 1600 whopping watts

passive subs are easier to place in room too, just speaker wire to worry about ... active subs need power cords and coaxial cables. easier to EQ and crossover because the amp is close to the equipment rack.

1600 watts? That's a very convservative rating for an EP2500 in bridged 4 ohm mode. Up to about 2000 watts is possible, maximum, with well under 1 percent THD, in 3rd party testing. 1600-1700 watts would be the maximum at the lowest frequency, say 20 Hz, or with line voltage sag issues, which is certainly likely to happen on the common circuit, assuming 30'-50' of 14 AWG under the particular current demands imposed. (Example: 40' run of 14 AWG with 15 amps drawn across it - would result in a 120VAC source voltage being reduced to about 108VAC by the time it was delivered to the load device.)

-Chris

 

[mike c]

yep, forgot to mention less than 1% THD at 20hz

 

[Sr SQ]

Sounds good guys
Mike did you build your own xover for your sub or did you have one built?
I feel confident enough in building a nice furniture grade type enclosure but I know the xover will be outside my realm so do you have any suggestions where to buy one?

-Sr

 

[GlocksRock]

if you are feeding your amp a lfe signal from the receiver, you wouldn't need a crossover since it's already crossed over coming out of your lfe output.

 

[mike c]

Sounds good guys
Mike did you build your own xover for your sub or did you have one built?
I feel confident enough in building a nice furniture grade type enclosure but I know the xover will be outside my realm so do you have any suggestions where to buy one?

-Sr

see glocksrock's reply below ... or above

the LFE output on the receiver is already low passed.

but if for some reason, you are using a 2 channel system or anything without a low passed subwoofer out, you can use ANY behringer model that starts with DCX. DCX2310 for example is the cheapest, around 100bucks. DCX2496 is the most expensive, but i believe has built in PEQ and a crapload of highpass, lowpass, and other cx tricks.

if you are feeding your amp a lfe signal from the receiver, you wouldn't need a crossover since it's already crossed over coming out of your lfe output.

 

[Sr SQ]

I don't know what LFE stands for?
Right now I am using the sub out on the Marantz to a Def Tec PF15
I didn't realize the sub out was crossed over for lowpass also, I know the active subs I have has a xover built in. I never seen anything in the manual about being able to select xover points or slopes on the Marantz so I assume the behringer models you suggested have selectable xover points

 

[GlocksRock]

LFE stands for Low Frequency Effects, it's the .1 in 5.1, 6.1, 7.1, etc... it's the channel dedicated to bass only.

 

[Sr SQ]

Thanks Glocksrock, I never heard it called that before.
So the amp just generically passes any frequency below.....say 200hz?
Then if I run the LFE control signal out of my amp into a separate Behringer amp it would only receive those frequencies below 200hz to amplify and send to the speaker?
What about the volume, will it be controlled by the main amp or will it need to be adjusted separately?

 

[ErinH]

Sr, are you perhaps, running a JL sub?

I actually am having trouble myself finding a plate amp to do ~700-1000w @ 3ohms for a DIY project with my 12w7. Also, at the prices I'm seeing for the others, I'm halfway wondering if I just wouldn't be better off selling the w7 and picking up a pre-made option. Though, I really like the idea of doing my own.