The Goal: I didn't want to tear apart alot of my truck ('05 Nissan Titan king cab)'s interior, so I decided to make a somewhat more "portable" sound system: So, I'm running my iPod straight into an amp, which powers a 10" sub & a pair of full-range speakers. The iPod is my only source of music, & I'm using no head unit ("HU") (although the OEM HU is still in place & connected).
The Stuff
* iPod
: Nano 16GB 4th gen. 2009 (
B&H Photo.com
$189.94 total)
* Amp
: Alpine PDX-5 (
eBay
$379.75 total) (Rated 75Wx4 RMS + 300Wx1 RMS (@ 2 or 4 ohms)) (Birth sheet says 121Wx4 + 424Wx1 (@ 2 or 4 ohms))
* Speakers
: Alpine SPS-600 6-3/4" coaxes (
Amazon
$69.95 total) (80W RMS/ 240W max) in rear doors only (for now). Doors sealed, deadened & poly-filled.
* Sub
: Alpine SWS-1043D 10" (
eBay
$175.10 total
for two
) (300W RMS/ 900W max) in 1 cu-ft sealed box under driver's side rear flip-up seat
* Line driver
: PAC TURBO 1 (
eBay
$24.99 total); I also added this line driver since, even though the system worked fine without it, most posters recommended it. Discussion below.
* Level controller
: PAC LC-1 (
Best Buy.com
$18.67 total); I also added this to control the volume with a knob rather than the iPod's pad controller. Discussion below.
(Below green are good results; red are bad)
Step 1
: Initial install
: I installed the Alpine speakers in the rear doors, set the amp under the driver's seat, & connected it all, including an 1/8" stereo-to-RCAs cable from the iPod to the amp's RCA inputs.
Results
were not very good. The speakers sounded pretty "tinny" with not much bass
.
Step 2
: Improve speaker install
: To reduce or remove the speakers' "tinny" sound, I read up & found that, to keep the back side of the speakers from being heard, & to provide the speaker with some pressurization, I needed to seal & deaden the doors. So, I sealed all door openings that I reasonably could using Second Skin Damplifier ("SSD") sound deadener. I also applied the SSD to any surfaces of the door that seemed to be resonant; I applied it to obvious large metals surfaces such as the door's outer skin, but also to any other surfaces that I could tap on & hear resonate. I also added some poly-fill to the door cavity.
Results
were very good! Much better bass
, even coming from the small 6-3/4" mid-woofers in the Alpine SPS-600's.
Step 3
: Added a sub
: (
eBay
$175.10 total
for two
) I didn't want to take up
all
of the rear passenger room, so I sketched & sketched & finally determined that I could make a sub box with a volume of 1.0 cubic feet that would fit under the rear driver's side seat, with the sub facing up, & allowing the rear seat to still latch down but not rest on the sub box. This would allow me to at least be able to throw my junk on the rear seat bottom. The box is sealed (not ported), & I put some poly-fill in it ($3 for a big bag at nat'l chain fabric store "JoAnn's"). The box size is 20"W x 7"H x 20"D (bottom)/ 17.25"D (top) (3/4" MDF) = 1.0 cu-ft interior volume. The sub-woofer is an Alpine SWS-1043D (300W RMS/ 900W Max), which has a recommended sealed box volume of 1.0 cubic feet. For portability, so I can easily remove the sub if I have a 4th passenger, I added a carrying handle & used a banana plug box terminal cup; I can take the sub out completely in about 6 seconds.
Results
WOW! Subs are awesome! This configuration pounds bass up against the back & bottom of the driver's seat, which is awesome
. Pics of the sub:
At this point, even though the amp's gains had to be turned way up, I thought the sound quality was great, it pounded pretty good, rattled the rear view mirror, & I had no noise whatsoever (unless charging the iPod), however read on ...
Step 4
: Line driver added
: (
eBay
$24.99 total) It somewhat concerned me when I found I needed to turn the amp's gain nearly all the way up (85-90%) in order to really make the system crank (with the iPod's volume nearly all the way up). I posted that & most replies said I needed a line driver in order to increase the audio signal's voltage so that it could be matched to what the amplifier wants. So, I installed a PAC TURBO 1. I measured the voltage of the iPod's audio output to be around only 0.004V. The PAC did what it was supposed to, increasing the voltage to about 0.04V. And,
this did add a noticeable "punch" to the audio quality
. However,
it also either added a source of noise
, or it's amplifying a pre-existing low noise so that it's now very audible. the noise is bad enough when driving with the iPod playing but not being charged; Plug in the charger & it sounds like it might damage the speakers. So ...
Step 5
: Noise filter added v1
: I found a cheap noise filter at Wal-Mart & decided to give it a shot. You simply plug it in line using its RCA connectors.
Results
It did nothing
, whether I wired it in line
before
the PAC line driver, or
after
. I have now removed it since it did not reduce the noise at all. The only way to listen with a tolerable, fairly low amount of noise is to not charge the iPod while driving. By the way, the system has no noise whatsoever with the truck not running; However, with the truck still not running, but then plugging the iPod charger back in, the noise is incredibly high again. So, it seems I may have 2 sources of noise: Alternator & ipod charger. Right now I don't know if it's poor wires, poor cabling, wires too close together, or cheap products: Stay tuned ... I have access to two electrical engineers (one's a PE) & meters; If it
can
be solved, we should be able to do it.
Step 6
: Noise filter added v2
: I bought 2 snap-on "chokes" from Radio Shack. These are filters that open easily & just snap closed around your wiring. I tried them on both the iPod's charging wire & on the iPod's audio output.
Results
They did nothing no matter what I tried
; No effect; Still had all the noise. Removed them & returned them.
Step 7
: Noise filter added v3
: (Where? $?) I bought a cheap ground loop isolator at either Wal-Mart or Pep Boys (gotta go look), wired it into the 12V power source feeding the PAC line driver.
Results
Excellent! The noise I was getting after installing the line driver is gone, even with the truck running
! I was very skeptical that this cheap item would do anything, but it did! However,
I still do get lots of noise when I plug in the iPod's charger
, so the search to fix that continues.
Step 8
: Noise filter added v4
: I bought a
PAC SNI1-3.5 ground loop isolator (eBay $8.45 total)
which plugs directly into the iPod's 1/8" stereo audio output, so it's right in line.
Results
Finally
all noise is gone
! Pic of it:
Step 9
: Level Controller added
: (
Best Buy.com
$18.67 total) I bought a PAC brand LC-1 "level controller", which is a volume contoller. I put this in line just before the line driver.
Results
Great!
I now have a volume knob I can quickly reach to and adjust without looking, just like a normal car stereo.
! It was kinda dangerous having to focus on the iPod to lower the volume while driving.
So at this point, my "music source" consists of: iPod -> Inline ground loop isolator -> Line Level Controller -> Line Driver -> Amp. (And, the Line Driver's 12V power feed has a ground loop isolator). I know this sounds like a hodge-podge of junk, but the sound is awesome!! It rocks my truck very hard. It gets louder than I can stand and pounds.
Step 10
: Front speakers added
: I've only added the front-passenger side speaker so far.
Results
coming soon.
Step 11
: iPod line-out instead of audio-out
: I've read the benefits of using the iPod's "line out" instead of the "audio out" that I'm using now:
- According to some, the iPod's built-in digital-to-analog converter (DAC) isn't very good quality (although I don't have any complaints about it). So, it seems that using a high quality adapter that uses the iPod's line out and has its own high quality DAC should provide better audio quality
- I think the iPod's line-out voltage is higher than the audio-out, which makes sense since the iPod's own volume pad controller would vary the voltage output level.
- Since I'm using a separate level controller, I don't need to be able to use the iPod's volume pad controller anyway, which is a function you lose when using the iPod's line-out signals.
The Stuff
* iPod
: Nano 16GB 4th gen. 2009 (
B&H Photo.com
$189.94 total)
* Amp
: Alpine PDX-5 (
eBay
$379.75 total) (Rated 75Wx4 RMS + 300Wx1 RMS (@ 2 or 4 ohms)) (Birth sheet says 121Wx4 + 424Wx1 (@ 2 or 4 ohms))
* Speakers
: Alpine SPS-600 6-3/4" coaxes (
Amazon
$69.95 total) (80W RMS/ 240W max) in rear doors only (for now). Doors sealed, deadened & poly-filled.
* Sub
: Alpine SWS-1043D 10" (
eBay
$175.10 total
for two
) (300W RMS/ 900W max) in 1 cu-ft sealed box under driver's side rear flip-up seat
* Line driver
: PAC TURBO 1 (
eBay
$24.99 total); I also added this line driver since, even though the system worked fine without it, most posters recommended it. Discussion below.
* Level controller
: PAC LC-1 (
Best Buy.com
$18.67 total); I also added this to control the volume with a knob rather than the iPod's pad controller. Discussion below.
(Below green are good results; red are bad)
Step 1
: Initial install
: I installed the Alpine speakers in the rear doors, set the amp under the driver's seat, & connected it all, including an 1/8" stereo-to-RCAs cable from the iPod to the amp's RCA inputs.
Results
were not very good. The speakers sounded pretty "tinny" with not much bass
.
Step 2
: Improve speaker install
: To reduce or remove the speakers' "tinny" sound, I read up & found that, to keep the back side of the speakers from being heard, & to provide the speaker with some pressurization, I needed to seal & deaden the doors. So, I sealed all door openings that I reasonably could using Second Skin Damplifier ("SSD") sound deadener. I also applied the SSD to any surfaces of the door that seemed to be resonant; I applied it to obvious large metals surfaces such as the door's outer skin, but also to any other surfaces that I could tap on & hear resonate. I also added some poly-fill to the door cavity.
Results
were very good! Much better bass
, even coming from the small 6-3/4" mid-woofers in the Alpine SPS-600's.
Step 3
: Added a sub
: (
eBay
$175.10 total
for two
) I didn't want to take up
all
of the rear passenger room, so I sketched & sketched & finally determined that I could make a sub box with a volume of 1.0 cubic feet that would fit under the rear driver's side seat, with the sub facing up, & allowing the rear seat to still latch down but not rest on the sub box. This would allow me to at least be able to throw my junk on the rear seat bottom. The box is sealed (not ported), & I put some poly-fill in it ($3 for a big bag at nat'l chain fabric store "JoAnn's"). The box size is 20"W x 7"H x 20"D (bottom)/ 17.25"D (top) (3/4" MDF) = 1.0 cu-ft interior volume. The sub-woofer is an Alpine SWS-1043D (300W RMS/ 900W Max), which has a recommended sealed box volume of 1.0 cubic feet. For portability, so I can easily remove the sub if I have a 4th passenger, I added a carrying handle & used a banana plug box terminal cup; I can take the sub out completely in about 6 seconds.
Results
WOW! Subs are awesome! This configuration pounds bass up against the back & bottom of the driver's seat, which is awesome
. Pics of the sub:
At this point, even though the amp's gains had to be turned way up, I thought the sound quality was great, it pounded pretty good, rattled the rear view mirror, & I had no noise whatsoever (unless charging the iPod), however read on ...
Step 4
: Line driver added
: (
eBay
$24.99 total) It somewhat concerned me when I found I needed to turn the amp's gain nearly all the way up (85-90%) in order to really make the system crank (with the iPod's volume nearly all the way up). I posted that & most replies said I needed a line driver in order to increase the audio signal's voltage so that it could be matched to what the amplifier wants. So, I installed a PAC TURBO 1. I measured the voltage of the iPod's audio output to be around only 0.004V. The PAC did what it was supposed to, increasing the voltage to about 0.04V. And,
this did add a noticeable "punch" to the audio quality
. However,
it also either added a source of noise
, or it's amplifying a pre-existing low noise so that it's now very audible. the noise is bad enough when driving with the iPod playing but not being charged; Plug in the charger & it sounds like it might damage the speakers. So ...
Step 5
: Noise filter added v1
: I found a cheap noise filter at Wal-Mart & decided to give it a shot. You simply plug it in line using its RCA connectors.
Results
It did nothing
, whether I wired it in line
before
the PAC line driver, or
after
. I have now removed it since it did not reduce the noise at all. The only way to listen with a tolerable, fairly low amount of noise is to not charge the iPod while driving. By the way, the system has no noise whatsoever with the truck not running; However, with the truck still not running, but then plugging the iPod charger back in, the noise is incredibly high again. So, it seems I may have 2 sources of noise: Alternator & ipod charger. Right now I don't know if it's poor wires, poor cabling, wires too close together, or cheap products: Stay tuned ... I have access to two electrical engineers (one's a PE) & meters; If it
can
be solved, we should be able to do it.
Step 6
: Noise filter added v2
: I bought 2 snap-on "chokes" from Radio Shack. These are filters that open easily & just snap closed around your wiring. I tried them on both the iPod's charging wire & on the iPod's audio output.
Results
They did nothing no matter what I tried
; No effect; Still had all the noise. Removed them & returned them.
Step 7
: Noise filter added v3
: (Where? $?) I bought a cheap ground loop isolator at either Wal-Mart or Pep Boys (gotta go look), wired it into the 12V power source feeding the PAC line driver.
Results
Excellent! The noise I was getting after installing the line driver is gone, even with the truck running
! I was very skeptical that this cheap item would do anything, but it did! However,
I still do get lots of noise when I plug in the iPod's charger
, so the search to fix that continues.
Step 8
: Noise filter added v4
: I bought a
PAC SNI1-3.5 ground loop isolator (eBay $8.45 total)
which plugs directly into the iPod's 1/8" stereo audio output, so it's right in line.
Results
Finally
all noise is gone
! Pic of it:
Step 9
: Level Controller added
: (
Best Buy.com
$18.67 total) I bought a PAC brand LC-1 "level controller", which is a volume contoller. I put this in line just before the line driver.
Results
Great!
I now have a volume knob I can quickly reach to and adjust without looking, just like a normal car stereo.
! It was kinda dangerous having to focus on the iPod to lower the volume while driving.
So at this point, my "music source" consists of: iPod -> Inline ground loop isolator -> Line Level Controller -> Line Driver -> Amp. (And, the Line Driver's 12V power feed has a ground loop isolator). I know this sounds like a hodge-podge of junk, but the sound is awesome!! It rocks my truck very hard. It gets louder than I can stand and pounds.
Step 10
: Front speakers added
: I've only added the front-passenger side speaker so far.
Results
coming soon.
Step 11
: iPod line-out instead of audio-out
: I've read the benefits of using the iPod's "line out" instead of the "audio out" that I'm using now:
- According to some, the iPod's built-in digital-to-analog converter (DAC) isn't very good quality (although I don't have any complaints about it). So, it seems that using a high quality adapter that uses the iPod's line out and has its own high quality DAC should provide better audio quality
- I think the iPod's line-out voltage is higher than the audio-out, which makes sense since the iPod's own volume pad controller would vary the voltage output level.
- Since I'm using a separate level controller, I don't need to be able to use the iPod's volume pad controller anyway, which is a function you lose when using the iPod's line-out signals.
