Pioneer Stage 4 - I Need Expert Speaker Hook-up Advice/Recommendations

[rewillia]

Hello Forum members. I am new here and need some "expert" advice on how to hook up my speakers in a custom install I am doing;

The configuration will be as follows:

1-Pioneer, 8-channel pre-amp/pre-out Stage 4 Head Unit model DEX-P99RS

1-Pair of FOCAL model 100KRS 4" component speakers which include both L&R 4" midrange + separate L&R set of 1.79" tweeters,

1-Pair of FOCAL model 165 KRX2 6.75" component speakers which include both L&R 6.75 woofers + separate set of 1.96" tweeters,

1-Pioneer 10" low profile SW-TS2501 sub-woofer.

2- Pioneer PRS 4200F 4-channel amplifiers

1- HD Radio Module

1- Sirius Sat Radio Bus Interface and Module

1- 5-FARAD Capacitor

Problem I foresee:

As indicated my HU has 8 pre-out channels (4-pair L&R) which serve to provide High/Mid/Low and Sub-woofer outlets to amps. I will have 9 independent speakers (4 Highs, 2-Mids, 2-Lows and 1-Sub).

I do not plan to use the crossovers that came with each pair of FOCAL component speakers unless I have to as the Pioneer Stage 4 HU provides the ability to set each channel for optimum sound performance.

My question (where I need advice);

How should I connect the tweeters?

Should I splice the L&R High range speaker out of my Amp 1 to feed both sets of tweeters or should I use the crossovers in between the High range speaker out and the 2-pairs of tweeters?

Note: this equipment is being installed in a vintage Mercedes 2-dr convertible roadster and the tweeters have been installed as follows:

1-Pair (L&R) 1.75" Tweeters installed in doors adjacent to dash mounted 4" Low range speakers

1-Pair (L&R) 2.00" Tweeters installed in rear deck area panels behind the two front seats at same height at the front tweeters (these will be positioned just to the side and behind both driver/passenger seat headrests) and will be apprx. 18" from the 6.75 Low (L&R) speakers which are being mounted in the rear cargo deck area behind the seats.

The sub will be mounted in a space underneath the rear cargo deck area.

Click to read more...

 

[keep_hope_alive Premium Member]

Only one pair of tweeters should be used.

Yes, run it all active.

Awesome system components. Install quality and effort will determine performance. See my build log for ideas on door treatments.

Remember that speaker airspace is vital to performance. Seals and absorption are needed.

 

[rewillia]

Thanks for your advice/feedback. Install quality has been a primary consideration and included sound absorbing/deadening material installation (floors, doors, side interior panels, etc) and included use of both Dynamat type material and 3M spray insulating foam. All chassis wiring (long leads) performed using shielded HQ audio cabling, sleeved and secured to ensure no interference (from other wired sources, e.g. power feeds), and carefully run/hidden.

Speaker installation was a challenge in the 1988 Mercedes 560SL 2-dr roadster/convertible as the fatory OEM audio only included 2-4" dash mounted speakers. I opted placement as follows:

Dash - 2 x Focal 100 KRS 4" mid-range woofers

Doors- 2 x Focal 165 KRX2 1.96 (~2") tweeters mounted at mid height at front of door panels (i.e. height of steering column)

Rear Deck: horizontal (located behind 2 front seats); 2 x Focal 165 KRX2 6.75" woofers

Rear Deck Panel verticals; 2 x Focal 100KRS 1.75 tweeters (immediately behind headrest)

Sub - 1 x Pioneer TS-SW2501S4 low profile 10" sub installed in custom fabricated fiberglass and MDF enclosure and positioned in floorboard void space below rear cargo deck area and hidden. (Note: sub will not be ported)

HD Tuner. Sirius Module to be located behind dash above glove box)

Amps (2 x Pioneer PRS-D4200F) to be located in trunk along with 5-FARAD Capacitor)

I consulted with both Pioneer (Tech support) and Crutchfield on installing all 4-tweeters and they both advised that the Stage 4 HU will handle them well (remember, the stage 4 has 8-channel pre-outs); and their advice was to split off to both pairs of tweeters from AMP 1 High range out (other amp channels will power the Mids/Lows and Sub).

Am now at a point where installation is 99% complete with only the final amp and cap installation remaining; I am planning to take the vehicle to an installation shop (car audio specialist) to wire up the AMPS, complete the hook-up then fine tune the set-up using the proper testing equipment, etc.

Will let you know how the 2-pair of tweeters work out as against your advice I plan to use them in order to gain compensating high and low range to balance with the performance that will come from the rear mounted 6.75 woofers and 10" sub. Am doing so as the car is a convertible and being a 2-seater will need the extra range up front.

If I were a professional installer I would consider that this car was one of the most challenging installations to perform given its limitations on space.

 

[>>SQL<< 10+ year member]

You have a 4 channel amp - what are you using to power your subwoofer?

Your 5 fared capacitor is completely worthless and is not needed in any way

You are going to need to use the crossovers supplied with your component sets as you do not have enough channels of amplification to run active.

 

[Kingstroker 10+ year member]

High quality set of 6.5 comp is all you need. I know I've bragged on Blues Audio/Linear Power before but have sat in the front seat of Mr Rayfield's car and listened to a variety of music. When he played rap at a moderate volume it sounded like he had subs, vocals and highs were clear even though the 6.5 were hitting about 32Hz(?) if I remember correctly, seemed lower. The amp was an under rated 250 wrms 2 channel Linear Power. Never heard more sound from 4 speakers, I couldn't imagine what it would have sounded like if it were active. Such a small area in a 2 seater, make some one a deal on set of speakers and cap or at least get rid of 1 set of tweets and the cap. Another benefit would be a lot less work.

 

[keep_hope_alive Premium Member]

sounds like you have put the time into the install. i was limited on time for my first response and wasn't able to go into more detail as to why i recommended what i did. you are welcome to run whatever you want in your car, you've already made the investment. just recognize that a great sound system is not achieved out of the box, but after hundreds of hours of tuning and tweaking. you may be happy when you get your car back, but know that 20 minutes of "tuning" is not going to get the most out of the system. don't be afraid to experiment further (it's fun and addicting). //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

i agree the capacitor is not doing any good and has no business in that system. it's a marketing ploy only. the money should have been spent on a very good AGM battery up front.

as it relates to rear tweeters, this is something you can experiment with yourself by disconnecting them and comparing before/after. the information below is intended for all, not just the OP, as a "summary" of my thoughts on rear speakers in general.

we'll start with some acoustics background on how we localize sounds.

above 3.5kHz we localize sounds based on IID or intensity. pathlength does not matter as much so time alignment is not necessary. this is why they told you to combine the tweeters on one channel, because they don't need to separate T/A. the front woofers, front mids, and rear woofers all need separate time alignment (6 channels). the sub will have it's own output eating up the other 2 channels. this means you're running passive crossovers with the 4" and tweets up front and the 6.5" and tweets in the rear.

you will need to rely on passive attenuation to make the nearest tweeter quieter than the farthest up front to shift the soundstage to the center. you will need to substantially attenuate the rear tweeters to prevent them from destroying the front soundstage. rear tweeters are never necessary. rear woofers/mids alone are capable of playing full range up to 4kHz or 5kHz which is plenty for the envelopment you desire without being distracting.

as it relates to rear speakers - think of it this way. you should not be able to notice they are on when the system is playing. it should seem like they aren't even there... except when you turn them off you will notice a change. using T/A on the rear speakers can allow you to adjust the sound stage a bit further. there is plenty of discussion on "rear fill" and how to properly implement it. what you want with rear fill is to enhance the depth and width of the sound stage, not distract from it.

in car audio, people have been obsessed with "needing" rear speakers. in home audio, we don't do that (except discrete surround sound which is not what we do with car audio). in pro audio we don't do that either. so why do we want rear speakers? i believe there are two reasons for this.

1. cars came with rear speakers to provide additional low frequency support. most cars come with rear woofers (no tweeters) for that purpose. the car audio industry wants to sell speakers, so they recommend buying all new full range speakers front and rear to double the investment. i feel you should just spend twice as much on the fronts and forget the rears.

2. in a car, we are in a very confined space. we lack the enveloping reflections that we get in a house or auditorium. as an Acoustics Engineer, i design listening spaces for auditorium, churches, performance halls, music rooms, etc. getting some reflections from the rear of the room is inevitable and desirable, but we pay careful attention to the frequency content (absorption), the time delay (Initial Time Delay Gap), and directionality (scattering/diffusion).

some people sit in a car with front only speakers and feel like there is an empty space behind them. this is usually because the front speakers were not properly installed/tuned.

as it relates to rear fill, there are two main schools of thought for how to tune the rears. both use only mids and no tweeters.

1. heavy delay (greater than 20ms) to simulate a larger space

2. delay as required to manipulate sound stage (closer to actual path length)

 

[Kingstroker 10+ year member]

@Keep_hope_alive, this is something I'm going to have to study a while to absorb most of it. It will be a couple weeks before I get my amp back so I will have time. Understanding the behavior of different frequencies and how our ears interpret them is very interesting(to me). Thanks for the brain candy.