S4 vs PDX4.150

[jblayz1 10+ year member]

Digital Designs-

Series

S

Input Sensitivity

0.2V - 8V

Variable High Pass Filter

20 Hz - 500 Hz (200 - 5 kHz) at 24dB/Oct

Variable Low Pass Filter

50 Hz - 500 Hz (500 - 5 kHz) at 24dB/Oct

Tested Voltage

14.4V

Tested THD

1%

Power at 4 ohm

100W x 2ch + 200W x 2ch

Power at 2 ohm

150W x 2ch + 300W x 2ch

Damping Factor

>550 @ 2 ohm

Power at 1 ohm

175W x 2ch + 350W x 2ch

Power at 4 ohm Mono

300W x 1ch + 600W x 1ch

Power at 3 ohm Mono

350W x 1ch + 700W x 1ch

Max Dynamic Power

400W x 1ch + 800W x 1ch

Efficiency thru Output

64%

Dimensions - mm

390 L x 235 W x 53.4 H

Dimensions - inches

15.35 L x 9.25 W x 2.1 H

Signal to Noise

95 dB

Shipping Weight

16 lbs

Alpine PDX4.150

RMS Continuous Power (at 14.4V , 20 - 20 kHz )

• Per channel into 4 ohms (≤1%THD+N) 150W x 4

• Per channel into 2 ohms (≤1%THD+N) 150W x 4

• Bridged into 4 ohms (≤1%THD+N) 300W x 2

S/N Ratio (IHF A Weighted , Reference: rated power into 4 ohms) 100dBA

CEA2006 S/N Ratio (IHF A Weighted , Reference: 1W into 4 ohms) 78dBA

Input Impedance 10k ohms

Frequency Response (+0, -1dB) 20 - 20kHz

Crossover Frequency ( Variable , L . P. F / H.P.F / OFF Selectable)

• 1/2 ch 30 - 400 Hz (-12 dB / oct)

• 3/4 ch 30 - 400 Hz (-12 dB / oct)

Input Sensitivity (V / at 10k ohms) 0.2 - 4.0V

Dimensions • Width 257mm (10-1/8”)

• Height 62mm (2-7/16”)

• Depth 192mm (7-9/16”)

Weight 3.11kg

these are for a front stage. opinions?

Click to read more...

 

[dragnix 5,000+ posts]

depends on wat kinda of speakers u wanna run (ohms wise) and possibly ur budget. But the alpine is smaller which I prefer

 

[jblayz1 10+ year member]

anyone else want to chime in here...?

 

[johnson 10+ year member]

What do you want to know? The S4 is more versatile and the PDX has smaller footprint and is more efficient.

 

[Flipx99 5,000+ posts]

I have the S4.

The S4/m1a is about the same price as the 1.1000/4.150 combo.

Here is some things to consider:

1) Are you going active

2) What drivers did you select

3) How much space do you have

I chose the S4a/M1a combo. It wasn't cheap but works well. In retrospect, I would have chose the 4.150/1.1000 combo as I could have really used the space.

But here is another consideration. Let's pretend you have a passive setup.

You can run 100w to each side, and bridge the rear channels to get 700w @ 1 ohm....effectively having a really nice 3 channel amp in a small space.

You can't really go wrong either way though.

Also..pea es:

Don't use the crossovers on the S4a (or 4.150 for that matter) if you want to go active, get a active capable HU or external processing.

 

[jblayz1 10+ year member]

i am using the S4 active with a 9887. i am currently experimenting with different drivers on the front stage. space is not really an issue, but the smaller footprint and higher efficiency on the PDX's would be nice. the flexibility of the S4 is nice because i don't need 2 amps for the front stage. the inefficiency on the S4 bothers me tho. passive setups IMO are inefficient too. i was thinking of running the mids off the PDX bridged, but that may be too much headroom. after speaking with another board member who runs similar front drivers with a PDX unbridged, i'm thinking the S4 will be just fine even though it's a bit inefficient. i should be getting the new mid drivers this week. they are 8ohm along with the tweeters. i have a feeling they will sound better than the drivers i have now. we'll see. thanks for the responses. hope to see some more suggestions/opinions...

 

[Flipx99 5,000+ posts]

If you are just looking at a published effecinecy, I run the m1a and s4a on a stock electrical w/ big 3.

One run of 0/1 from battery to a distro block where I split into two runs of 4 ga to the amps. 0/1 grounded to frame.

I don't get any dimming.

Do you already have the S4a?

What drivers do you currently have?

 

[jblayz1 10+ year member]

yes i have the S4 already. i run an re12.1 to the sub. no dimming. no big 3. stock electrical. i have the PhassHR series comps(4 ohm mids) which sound really nice with the MX mode on the HU turned to 3. But with the amps i have, i don't see why i need to set the MX mode to anything for it to sound strong. does that make any sense? i do however need to stop being lazy and upgrade to 4ga power. maybe the 4ga power to distro block with 2 8ga is not enough current? the amps read 13.7v at idle.

sorry if my retardedness is obvious and i don't see it.

i also noticed that after i set the gains on the 1/2 channels of the S4 and played some music for a couple days it changed. it read between 11/11.5v after i set it and played music. i set it to 10v the first time, checked it after a few days and it read 11.3v. i thought that was weird. yesterday i set it to 14.1v and haven't checked it yet.

 

[Flipx99 5,000+ posts]

yes i have the S4 already. i run an re12.1 to the sub. no dimming. no big 3. stock electrical. i have the PhassHR series comps(4 ohm mids) which sound really nice with the MX mode on the HU turned to 3. But with the amps i have, i don't see why i need to set the MX mode to anything for it to sound strong. does that make any sense? i do however need to stop being lazy and upgrade to 4ga power. maybe the 4ga power to distro block with 2 8ga is not enough current? the amps read 13.7v at idle.
sorry if my retardedness is obvious and i don't see it.

i also noticed that after i set the gains on the 1/2 channels of the S4 and played some music for a couple days it changed. it read between 11/11.5v after i set it and played music. i set it to 10v the first time, checked it after a few days and it read 11.3v. i thought that was weird. yesterday i set it to 14.1v and haven't checked it yet.

I thought you where supposed to set amps, not volts.

Anything less than 13.5A at the amp is bad, imo if the car is on.

 

[jblayz1 10+ year member]

i'm talking about the gains.

 

[bikinpunk 10+ year member]

PDX's. Your h/u is doing the crossovers. You just need power. At the power, footprint, and efficiency (I've seen 90%+), get the PDX.

done and done

 

[Flipx99 5,000+ posts]

Right, I am thinking you set the gains by amps, not volts.

 

[Flipx99 5,000+ posts]

Then he'd have to sell the S4a.

 

[bikinpunk 10+ year member]

Then he'd have to sell the S4a.

I'm lost here.

He has a 9887, but is running passive. He wants PDX due to smaller footprint, but the S4a allows him to use just run amp, correct?

Why not just go active? In that case you'll still have to add a 2nd amp anyway.

Or am I missing something here?

 

[bikinpunk 10+ year member]

Right, I am thinking you set the gains by amps, not volts.

Set gains by volts.

Use ohms law. P=R*V^2

So, you know what power you want, you know resistance. Rearrange the equation and you get:

V= square root (P*R).

so, you're ultimately trying to dial in the voltage on the DMM to what you have calculated using that equation.