Crystal 8 or ID8 v3???

[ed94r]

The Crystal cmp8 is a 4 ohm only sub. The ID8 can be had in a DVC 4 ohm, effectively a 2 ohm resistance to the amp. I am certain that I want a sealed enclosure, firing rearward w/ stock premium speakers removed from their housings to act as early stage vents.

The amp is a "old school" Soundstream 644 75x4, 75 each running to the front separates, and ch 3&4 bridged to power the sub.

The question: run a 4ohm load to the crystal, or a 2ohm (and more RMS) to the ID8?

Additionally, the crystal requires a .9 sealed enclosure for SQ, and the ID8 requires a .35 sealed.

I am leaning to the ID8, but am not familiar w/ subs so I am asking others opinions. Music preferences: Mostly folk, softer side of rock (Jack Johnson, Ben Harper,etc...).

TIA, Ed

[KenC]

You're going to bridge channels 3 and 4 to a 2ohm (effectively) sub? I'm pretty sure that Soundstream isn't 1 ohm stable.

Get the 4 ohm Crystal and then when you bridge 3 and 4 they'll be running at 2 ohms.

[ed94r]

Maybe I should clarify,

ID8: Available with 2, 4 ohm VC's= 2 ohms.
Crystal8: Only available as a single VC 4 ohm.

According to the literature w/ the amp, stable to 1/2 ohm but I'm not going to drive it that far. I'd like to drive the amp @ 2 ohms (ID8) vs. 4ohms (crystal8) for more rms. What I'm trying to figue is if it's necessary to run 2 ohms (and the reulting increase in RMS) to achieve low fill or will running a 4 ohm crystal be adequate. I like how well the crystal did in the "great 8 soundoff" and that's the only reason I'm even considering it. If I'm wrong about how this all works, I appologize, for I'm new to this car audio biz and I'd rather learn than pay someone to do it for me.

Amp: Soundstream Rerfence 644S (1995) 75x4 4/3/2 capable.
Front fill: a/d/s 235is
Head: Nak CD400
Sub: ???

Thanks

[KenC]

I know Soundstream made some beastly amps back in the day, but 1/2 ohm stable!? In a 4-channel!?

You'd need to run at LEAST 2 ga power and ground to it with a cooling fan.

[ed94r]

I have a ?
example:
If I have a 100x2@ 4 ohm.
If I bridge the two channels, will it be approx 200x1@4 ohms? Or 2 ohms?

Will the output resistance change by bridging? I thought that the above example would yield a 200x1@ 4ohm's. Let me know if I'm wrong, cuz if/when I am, it changes averything.

Thanks

The amp is 1 ohm stable, not 1/2. I'm gonna get this right one day.

[KenC]

If it's 100x2 at 4 ohms, then when you bridge it, it will be 400x1 at 2 ohms.

[ed94r]

so would 200x1 @4ohms not be possible in the above situation?

[KenC]

so would 200x1 @4ohms not be possible in the above situation?

Not unless you're bridging the amp to an 8 ohm sub.

[ed94r]

so would 200x1 @4ohms not be possible in the above situation?

Not unless you're bridging the amp to an 8 ohm sub.

PM sent. Can you please help. I'm in over my head.

Ed

[808BMW]

I know Soundstream made some beastly amps back in the day, but 1/2 ohm stable!? In a 4-channel!?

You'd need to run at LEAST 2 ga power and ground to it with a cooling fan.

I've seen it done, made me give a whole lotta respect for "small old amps"
Same for rockford :P

[KenC]

I know Soundstream made some beastly amps back in the day, but 1/2 ohm stable!? In a 4-channel!?

You'd need to run at LEAST 2 ga power and ground to it with a cooling fan.

I've seen it done, made me give a whole lotta respect for "small old amps"
Same for rockford :P

Yeah, I just read the specs for that SS. According to them you'll gain only 20 watts going from 2 ohms to 1/2 ohm.

I'd love to get an old RF Punch 100dsm