Car Audio

[Derek Cohen]

I am about to pull the trigger on an upgrade for my car audio. Perhaps some will have opinions here.

The car is a 2001 Porsche Boxster S (known as a 986), which I have owned for about 15 years. The car is a great joy to drive, in excellent condition, and plan to keep it as long as I can get in-and-out without looking like a complete idiot! :)

It still has the original audio system, which comprises a Becker radio/CD with 6 speakers (dash, doors and rear parcel tray). I love listening to music in the car, but a “decent” audio system has been an extravagance I could not justify in the past (I have a decent audio system in the house, and even a very modest system in the workshop/garage). It is not just audio, but having a screen for GPS (better than using my iPhone) and a backup camera.

I’ve done the research and settled on the Alpine ilx-507a head unit, which is a new wireless model with Apple Play. There is a corresponding rear camera. The issue for me are whether I upgrade all the speakers, and whether I add an extra amplifier.

The head unit has outlets for 4 speakers, and I have seen a video where two extra amps were added to feed the 6 speakers. I am not clear whether this was done for the connection or the extra output - would an even higher output improve sound, assuming that the head unit has enough to drive what is there? Would more efficient speakers be the same/better? I have purchased one set of extra speakers for the doors (from Focal). The dash and rear could be done later (it is getting expensive, and there is also installation costs to add it - too complicated for me. Some components, such as the air con, will need to be re-located on the console. I’ve been quoted 6 hours).

Thoughts and comments welcomed.

Regards from Perth

Derek

[Jim Becker]

Biggest bang for the buck with vehicle audio is often in the speaker/amp arena, honestly, but upgrading that head unit to something modern is still a very good idea. In fact, it's nice that you can do that because it's no longer possible with many current generation vehicles. Any audio upgrades for current generation are pretty much limited to amp/speakers because the head units also control a "yuge" amount of the vehicle electronics.

As far as your options for speakers/amps, you might want to check out the US website for Crutchfield...it's a great information source, even if you can't practically buy from them in your geography. There's a lot of good information there.

[Greg Parrish]

Been a long time since I dabbled in car audio but if you can find any of the Arc Audio KS 125.2 or 125.4 amplifiers still available, they are outstanding and super compact. In a sports car, the smaller size will probably be appreciated and these things are tiny. Class GH digital amplifiers done right. There may be newer versions of these from Arc or other manufacturers these days.

Of course, the gold ole days were when you could buy power hungry Class A and Class AB amplifiers for the car but they were huge, took lots of input power and put out tons of heat. The Class GH amps were game changer when they came out in my opinion. Especially if you want to hide the amp and not worry about showcasing it.

http://content.arcaudio.com/pdfs/reviews/product-reviews/mini4.pdf

Also any of the Robert Zeff designed amps are considered to be good. His work was not just with Arc Audio but included brands like Zapco, Clarion, etc.

[Jim Braun]

Derek,
Not sure if you have considered Porsche's PCCM Plus (support for CarPlay) for your 986. I have a 981 Cayman and am awaiting the arrival of PCCM Plus for the 981 generation. Also depends on what kind of music you listen to in the car, a Boxster I had one, is not an environment for a critical audiophile.

https://content.us.porsche.com/prod/pag/classic/ClassicBildressourcenLive.nsf/76A23463C9BAFA3CC12585530021D4A9/$file/CL20Z20ID0001_1_lowthumb.jpg


https://content.us.porsche.com/prod/pag/classic/ClassicExplorer.nsf/ClassicPartsExplorerCampaign?ReadForm&cati=pccm&country=usa (https://content.us.porsche.com/prod/pag/classic/ClassicExplorer.nsf/ClassicPartsExplorerCampaign?ReadForm&cati=pccm&country=usa)

jim

[Derek Cohen]

Biggest bang for the buck with vehicle audio is often in the speaker/amp arena, honestly, but upgrading that head unit to something modern is still a very good idea. In fact, it's nice that you can do that because it's no longer possible with many current generation vehicles. Any audio upgrades for current generation are pretty much limited to amp/speakers because the head units also control a "yuge" amount of the vehicle electronics.

As far as your options for speakers/amps, you might want to check out the US website for Crutchfield...it's a great information source, even if you can't practically buy from them in your geography. There's a lot of good information there.

Thanks Jim

I have been on the Crutchfield website several times. They have great reviews and information, plus specific guidelines for equipment for many cars, including my own.

Regards from Perth

Derek

[Derek Cohen]

Been a long time since I dabbled in car audio but if you can find any of the Arc Audio KS 125.2 or 125.4 amplifiers still available, they are outstanding and super compact. In a sports car, the smaller size will probably be appreciated and these things are tiny. Class GH digital amplifiers done right. There may be newer versions of these from Arc or other manufacturers these days.

Of course, the gold ole days were when you could buy power hungry Class A and Class AB amplifiers for the car but they were huge, took lots of input power and put out tons of heat. The Class GH amps were game changer when they came out in my opinion. Especially if you want to hide the amp and not worry about showcasing it.

http://content.arcaudio.com/pdfs/reviews/product-reviews/mini4.pdf

Also any of the Robert Zeff designed amps are considered to be good. His work was not just with Arc Audio but included brands like Zapco, Clarion, etc.

Thanks Greg

The Alpine ilx-507a is a very up-to-date head unit - I needed to be sure that the technology will be around for several years. Of note, it has wireless Apple Play, will stream Tidal (which I do at home), will play Hi Res FLAC files (from a USB port - I plan on adding a SSD), and has the first Class D amplification for a car audio unit. The amp in my home set up is a Class D made by Devialet (a French company).

Regards from Perth

Derek

[Derek Cohen]

Derek,
Not sure if you have considered Porsche's PCCM Plus (support for CarPlay) for your 986. I have a 981 Cayman and am awaiting the arrival of PCCM Plus for the 981 generation. Also depends on what kind of music you listen to in the car, a Boxster I had one, is not an environment for a critical audiophile.

https://content.us.porsche.com/prod/pag/classic/ClassicBildressourcenLive.nsf/76A23463C9BAFA3CC12585530021D4A9/$file/CL20Z20ID0001_1_lowthumb.jpg


https://content.us.porsche.com/prod/pag/classic/ClassicExplorer.nsf/ClassicPartsExplorerCampaign?ReadForm&cati=pccm&country=usa (https://content.us.porsche.com/prod/pag/classic/ClassicExplorer.nsf/ClassicPartsExplorerCampaign?ReadForm&cati=pccm&country=usa)

jim


Jim, without even comparing which head unit is better (and they appear similar in many ways), the PCCM is three times the price of the Alpine. I suspect one is paying for the Porsche name (and then some!).

Alpine: https://www.crutchfield.com/p_500ILX507/Alpine-iLX-507.html

https://images.crutchfieldonline.com/ImageHandler/trim/750/457/products/2022/4/500/g500ILX507-F.jpg

As to music, not head-banging rock! I mainly listen to jazz, especially 60's.

Regards from Perth

Derek

[Tom M King]

Thanks for this thread. I've been needing to change the receiver in my truck for years, with only the FM working for those years, but just didn't think about it. I've been wanting a backup camera too, but just put off thinking about installing one of those too. This head can fit in my truck with Crutchfield even having the right mount and plugs on cables. The old amp and upgraded speakers still work great. The price is actually a lot less than I guessed it would be.

[Derek Cohen]

Before this question is lost ...


The issue for me are whether I upgrade all the speakers, and whether I add an extra amplifier.


Regards from Perth

Derek

[Greg Parrish]

As Jim pointed out above, biggest improvements come from speakers and amplification. I know you like to do things the right way, not just the throw money at it way, so personally I'd recommend just trying the head unit first to see what you think. If it gets loud enough but still doesn't sound great, then go to better speakers. You can always change out the speakers without having to pull the head unit out again. With speakers, I'd focus the money on the front end speakers and leave the rear speakers alone unless they are damaged. Lastly, if still not what you're after, then look at adding a higher quality amplifier than what's built into the head unit.


Before this question is lost ...




Regards from Perth

Derek

[Jim Becker]

I think that I agree with Greg here, especially since the new head unit is a given so you have support for modern features and capabilities. See how that sounds with the existing speakers, etc., and then work from there to fine tune it to what you like. It may be fine with stock speakers; it may benefit from some replacement speakers or all replacement speakers; those replacement speakers may or may not need additional amplification, etc. Do it building block style.

[Derek Cohen]

This is the video that has lead to questions for me. In this video, the (Australian) installer is fitting an Alpine ilx-702, which is a similar model (actually, the predecessor of the one I am getting). The car is a Porsche 996 (911), which is essentially the same car as mine. He leaves the speakers stock. The head unit has 4 channels out, which means it can power of 4 speakers. The Boxster, however, has 6 speakers. Consequently, he adds two amplifiers (Alpine KTP-445U). Each of these has a 4 channel out, making 8 channels, and enough to power up all the speakers. The upshot is higher power (which is going to improve sound through extra headroom) and coverage of all speakers (with two extra over, which could power a sub woofer, if ever needed).

It is the coverage for all speakers that caught my eye.


https://www.youtube.com/watch?v=JGTXvq2h4LA&ab_channel=TheFittingBay

I must add that there has been more discussion here than on the few audio forums I visited. That was a waste of time. Thanks all of you.

Regards from Perth

Derek

[Ron Selzer]

"The head unit has outlets for 4 speakers, and I have seen a video where two extra amps were added to feed the 6 speakers. I am not clear whether this was done for the connection or the extra output - would an even higher output improve sound, assuming that the head unit has enough to drive what is there? Would more efficient speakers be the same/better? I have purchased one set of extra speakers for the doors (from Focal). The dash and rear could be done later (it is getting expensive, and there is also installation costs to add it - too complicated for me."

Based on long ago experiences, you are handling this properly, next step would be an amp. then replace the rear speakers. I would not replace the dqash speakers due to the labor required for the little gain you will get. The car noise will override the gain from the dash speakers. Do what you feel you can comfortably afford as time goes by. Very easy to spend someone else's money.
Ron

[Malcolm McLeod]

... The car noise will override ...

'Audiophile' quality stereo in a Porsche is fabulous.... until the light turns green. After that, my off-key whistle-humming sounds identical. Save the coin for an extra run at Pikes Peak. Just MHO.

:D(2008 Cayman S in Cobalt Blue):D

[Warren Lake]

sat in a 2004 Merecedes once motor off stereo adjusted a bit playing one of Gino Vanellis albums. Sound was excellent, no road noise great recording great song writer and singer and stellar musicians. Past lifetime in many top recording studios had a bit of a reference. Not as much now. Her other mercedes newer higher model with Harmon Kardon. Cant say I preferred the sound over the Blaupunk in the 2004. Her 2005 Corvette had a bose system. WIth the Borla exhaust you really didnt hear the stereo. Motor turned off as best as i could tell the stereo sounded like cardboard.

As a yute we hooked up a transistor radio to an Kef and coles five way transmission line with Falcon cross over. One or two high frequency drivers were Coles forgot the numbers 4001 or 3001 maybe. The volume was low but the sound made us laugh it was so good. Speakers are a big deal in that case the source was crap but the sound was impressive.

I thought about upgrading my truck stereo but whats next keyless entry and push button start?

502572

[Derek Meyer]

I did a complete Alpine system in my 93 Explorer back in the 90's. I replaced the head unit with a CD unit that had optical outputs, and installed a signal processor that had optical inputs, along with a 6 disc CD changer. I had three amps, one 4-channel amp for the front mids/tweets (in custom kickpanels), one 2-channel for the midbass (located in the doors) and one 2-channel for the subwoofer (bridged into one channel). Once I got it installed and adjusted, it sounded phenomenal - imaging was spot-on and the sound quality was really high. I had an installer from a high-end place in Spokane listen to it, and he told me that, at the time, it was one of the two best sounding vehicles he had ever listened to.

I leared a lot about what constitutes good car audio from this project. One - you need tons of power in a car system if you want to listen at medium to high volumes while driving. Road noise is a killer and you need power to overcome it, especially at the low end. I built a custome subwoofer box that had two Alpine 12" DDDrive subwoofers, bridged together to a 2 ohm load. I ran these from a 2 channel Alpine amp that was bridged, so the load was effectively 1 ohm. I called Alpine and discussed this with an engineer, and he assured me that the components would handle this configuration, and even gave me dimentions to build the box to for the best sound quality. It was a sealed box with 1.4 cubic feet per woofer, filled with polyfill. I built it from 1" MDF and lined it with V-Blok, a sound deading membrane made by Cascade Audio. That box was really heavy, but really inert. The amp could produce 900W RMS into its 1 ohm load. It had an 80 amp fuse on the power line, which was a 4 gauge copper line that came from the battery. I also had a 1 farad stiffing capacitor to deal with the large transients that loud bass notes produce. The mid-bass speakers were driven by an amp that was 100w per channel RMS, and the front stage was 50w per channel RMS. I used the digital crossover in the signal processor, which also provided equalization and time alignment. It was a great system.

I recently upgraded the system in my 2020 Edge by replacing all the speakers and amps with aftermarket gear. This time, I had a local shop do the work and bought all the equipment from them. All I can say is, wow, talk about expensive! It was about twice as much for the install as I expected. They did a great job and the system sounds fantastic, though it does not play as loud as I thought it might. That doesn't matter now, though, as 53 year old me doesn't listen at the same volume as 27 year old me did. They used Hertz amplifiers, which have all the processing built in now (eq, time correction, level adjustment) and Audison speakers. I went with one 12" sub in a custom enclosure that fits in the spare tire well. They used a signal converter that connects to the head unit's outputs and converts them to digital to feed to the amps. It also has analog input-output if needed.

If I had it to do over this time, I'm not sure I would have had it done. The factory system wasn't bad, so this upgrade was not the night/day change that my old Explorer was. Plus, I didn't do any of the work myself this time, so I didn't have the same satisfaction at the end of the project. I'm still on the fence about whether the money I spent was worth it. Maybe my expectations were too high, but I did expect better performance than I got.

[Greg Parrish]

Yeah, my 2020 Explorer has the upgraded sound system in it with subwoofer. Can’t remember if it’s a JBL, Harmon, or what system. It’s not bad for a factory system. If i had one gripe it would be that the Sync system sucks for use with Apple Car Play. It’s been such a pain over the last 2 years. If you plug the phone in or touch any buttons in car before all the ford systems finish booting up it just will not ever connect to apple car play. Plus, it doesn’t do wireless car play like our BMW X5. Otherwise, its been fine for me.

[Derek Cohen]

Very interesting and helpful posts. Thanks all.

The realisation is crystallising that more power is needed than the head unit can supply. The Alpine ilx-507a gets absolute rave reviews, for screen, speed, connectivity, sound quality, etc. However it is just 18 watts RMS (50 wats music power, which is a nonsense measurement), and has 4 speaker outlets. Power to 6 speakers will lower this further. Now I know that we only need a couple of watts RMS to get sound, and probably 5-8 watts rms would be sufficient … if the car was stationary and the motor off. But this car is a convertible, and there is competing noise from the engine/muffler, wind, road, and environment. The video (I referred to earlier) uses a hardtop Porsche 911 (996 generation, which is the same as the Boxster 986 from the nose of the car as far as the seats). The music was presented in a workshop, not on the road.

More power needed. Alpine makes a D-class amplifier specifically for this head unit. Two will be needed to ramp up the outputs to the 6 speakers. This is the amp in the video. The blurb for the amp states: The KTP-445U Universal Power Pack amplifies the head unit power output, resulting in up to a 150 percent power increase over the original power from the head unit's built-in amplifier.

I suspect that others here will agree, but it would be reassuring to know if this sounds right as I need to contact the installer and confirm my order.

Regards from Perth

Derek

[Greg Parrish]

Sounds right to me, just remember than 18w from a head unit or even some of the head unit extension amps is not equal to 18w from a true separate amplifier. Kinda like the way a hand held router or shop vac says its 3 hp but its not equal to a 3hp motor on a shaper. You will get much more solid power, sound and headway from a true separate amp. I don’t know that head unit or the specific amp, but my guess is that it is a smaller amp similar to what’s in the head unit.


Just take a look. The KTP-445U only has a 15 amp fuse. https://www.crutchfield.com/p_500KTP445U/Alpine-KTP-445U-Power-Pack.html

One of the Alpine Separate amps has 90 amps of fuse. https://www.crutchfield.com/p_500RA90S/Alpine-R-A90S.html?tp=78740

I’m sure the KTP-445U will expand the output number of channels from the head unit, but if you want real, clean power with plenty of overhead capacity, you should look at the truly separate amps to cover all 6 speakers.

It’s just like home audio. A receiver with 14 channels built in will sound fine until you push it. Then as power output goes up, THD levels, noise and distortion also go up. But if you replace those channels with true outboard amps, you gain a new level of clean, powerful sound with plenty of reserve power when called upon. I know I’m pushing you to spend your money, but for someone with a nice system at home, the similar system in the car will be appreciated.

Regardless, I still say start with the head unit and work your way out from there. It will become diminishing returns like anything. Your biggest bang for your buck will be a head unit with low noise floor/level, a high voltage line output to an outboard amp with low noise floor/level feeling solid, clean power to a set of reasonably efficient speakers. More to it than that, but those are the basics for solid, clean sound.

[Derek Cohen]

Thanks Greg.

I looked at the larger amp (R-A90S). Three strikes against, although it looks to be the better amp: it is not available, and if it was it is quite a large unit and unlikely to fit in the available space. The smaller KTP-445U is less than half the size, will fit where the existing amp is installed, and also about a third of the cost. I would be using two, each of which is 45 watts per channel (a total of 8 channels). And is available.

Regards from Perth

Derek