Not sure

[denisno1]

Hi guys,yesterday i went to a audio car shop and they recomended me the sub Alphine r2-w12d2 + the amp pionner gm-d8701

to be honest i am not pleased for the quality i get…i paid 400£ just for them i needed as well a special box for the sub (the box doesnt have a hole , they said thats not important..)bcs of my car (e93 2007 convertible)
I didnt touch yet the control from the amp for gain and freq
sometimes is too much bass ,sometime is flat base
If i try to turn the base from the remote (the amp got that) then it sounds good but its start cliping,again it might be from the amp controls i didnt touch it yet

But what do you think guys is the amp strong enough for the sub?

Click to read more...

 

[technobass 10+ year member]

The amp are 800rms at 1ohm perfect for the sub, set the crossover on the amp to 80hz.

 

[Adel]

I have the same amp, and it's driving me crazy, sometimes it sounds great, and sometimes as if the subwoofer is off,
It's not a connection issue, I had a pioneer GM-A series it sounded more full and didn't face this issue but I replaced it cause it gets very hot to an extent that was afraid it could catch a fire. Didn't face any heat issue with this class D amp

 

[Doxquzme Premium Member]

It’s always important to remember that when you go to a stereo shop for advice, they will always lean on products that they retail, nothing else. That said, I've used the GM-D8701, 8604 and 9601's, most all of the GM-D series (and PRS) amplifiers extensively and they consistently produce to rated power and stay relatively cool – never blown one yet! This amp and sub should work well together. That is a decent subwoofer and it doesn’t lean towards a sealed (what you have) or ported (the one with the “hole” in them). Here is what the alpine site says.

Enclosure Compatibility

Sealed Box Volume: The recommended sealed box volume (gross) range is from 0.65 (18.4 liters) to 1.1 ft³ cubic feet, (31 liters) with 0.85 ft³ cubic feet (24 liters) being the ideal size.

If you are on the small side of this, may want to up the size of the box. Additionally, .5 to 1 pound (.25 to .45 Kilo’s) of Acousta-stuf will improve the overall sound of your sealed setup, in my experience, quite a bit.

Ported Box Volume: The recommended ported box volume range is from 1.1(31.15 liters) to 1.6 ft³ (45.3 liters) The ideal size is 1.55 ft³ (43.89 liters) using a slot port measuring 12½" (width) x 1½" (height) x 22" (length), resulting in a tuning frequency of 36 Hz.

As was mentioned earlier, I would set the crossover to 80Hz to eliminate possible peaks from popping up above that frequency and stuff the box with Acousta-stuff, you should see a real difference. If you are clipping then you most likely have the gains set incorrectly. Go back to the shop and ask them to help you set the gains and the crossover, that’s the least they should do. 800 watts to that sub should be putting out some serious volume. Are using an LOC to the amp from the head unit for signal? If you are, that could be the source of the problem too.

 

[nauc 10+ year member]

set the gain right, heres how. test tones are at the very bottom...

Amplifier Level Setting Guide

Note:The following article describes the Amplifier Level Setting process for most car audio amplifiers, regardless of brand. Specific target voltages for applicable JL Audio amplifiers are included...

jlaudio.zendesk.com

 

[audiobaun 5,000+ posts]

I would have opt. for an Aero ported enclosure and a different mono amp for that sub, But ..thats me