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swinada 08-08-2007 03:25 AM

Stereo sound system ???
Since my bus does not have a sereo system do i have to put something in there.
I have never installed a sound system with a Amplifier yet just always the regular wiring directly from the Unit to the speakers.
Now since this bus is a little larger then the average car or van I was thinking on putting an AMP in to get a little more sound. (dont know yet how much driving noise the bus creates and how far I have to turn the music up to cover it)
I have an old Sub sitting around that I took out of a Van because we needed the space the Sub took away. Attached to the sub is a Rockford PUNCH 100z2 ( Now question is can I somehow use this AMP for all my speakers or should I just leave it for the SUB (single 4 OHM sub) and buy something else for my regular speakers? I was planning on putting 6 in. 3 on the left 3 on the right.

swinada 08-10-2007 03:08 AM

Re: Stereo sound system ???
nobody got anything to say about stereo systems??? You guys all live without tunes???

Steve 08-10-2007 10:25 AM

Re: Stereo sound system ???
I have a massive sound system in my bus, way to complicated than you would want :lol:

the_experience03 08-10-2007 01:08 PM

Re: Stereo sound system ???
I'm sorry-I read this post when you originally made it and meant to respond, but forgot after work.

Here's my recommendation first of all. Go with multiples of 4 when it comes to setting up the speakers. The reason has to do with ohm loads and that good garbage. Six is an odd number that CAN easily work, but I think 8 would be a better option. I'm sure you can find a deal on speakers on eBay or I have a couple of friends who have bought from the no B.S. site with good luck. Ebay will likely be a little cheaper.

If I were you I'd keep that amp on the sub. It's well suited to that purpose, but will not run 4, 6, or 8 speakers real well. Go and get yourself a 4 channel amp. Remember, used is ok most of the time with name brand stuff. Make sure it is capable of running 2 ohms stereo if you want to run 8 speakers. Again, name brand stuff should be able to. If it gives a "bridged" rating or a power rating of 2x ...watts@4 ohms it will work fine if it's a 4 channel amp.

When you go to wire in the speakers you will be wiring them in pairs. You will have a right front pair, left front pair, right rear pair, and left rear pair. Simple, right? Run the positive and negatives from each speaker to their respective positive and negative outputs on the amp. Alternatively you could use heavier gauge wiring from the amp to the first speaker and tie the positive and negative terminal in to that wiring from the second speaker in at the first speaker of the pair to save on some wiring.

You will also need to get a head unit with 3 pairs of RCA preouts. You could use high level inputs, but RCA's are WAY easier and cheaper in my experience. You will run the left and right front and rear outputs from the headunit to the head unit to the amplifier. You could use the third output (marked sub) for running your subwoofer or just not use it for now.

The end result will be that you will still have stereo sound AND a working front and rear fader. That way you could listen to just the 4 speakers in the back or just the 4 speakers in front which is nice if they are in different rooms within the bus. The amp will be loaded to 2 ohms stereo which is a pretty easy load for it to handle. It will get warm, but in my experience a 4 ohm mono load on a 4 ohm stereo amp (a 4 channel is essentially two of that setup in one) is tougher than 2 ohms stereo for an amp and most can handle that JUST fine.

Now it's time for my word of caution on speaker and amplifier selection. Get decent speakers. I know you're buying 4 pairs (I hope I've convinced you of that) so it can get spendy, but look for the ones with the largest frequency response range and the greatest efficiency noted in dB per 1 watt meter. The difference between a speaker that runs 90dB w/m and one that runs 93db w/m will be twice the sound for a given input power. That's a pretty staggering difference. :shock: I would look for speakers in the 6.25 or 6.5 inch range. They actually have a larger motor structure on them than most 6x9's which have a 5.25 or 5.5 inch speaker's motor structure with a large, odd shaped cone. Remember, soundwaves travel in a circular pattern so if a non-circular cone is pushing them the waves will hit the surround at different times and it won't sound AS clear. This is why I'm not a huge fan of the odd shaped subwoofers out there. They might move more air for a given footprint, but they don't sound as tight. I guess it's just a personal preference....

When you go looking for an amplifier you are going to need a 4 channel amp capable of running 2 ohms stereo as I posted before. Having a level adjustment and high pass crossover is important in my book, but a lot of that can be accomplished through a decent head unit. So what's the most important thing I look for? Look for the nominal/continuous/RMS wattage rating. Peak or max power mean NOTHING. There is no god standard for figuring it out. I question whether some amplifiers would be capable of putting out their peak power when struck by lightning. Match the stereo 2 ohms RMS output to the speaker's RMS input and you will be happy. Also try and stick to a THD (total harmonic distortion) of <.5 as you won't be able to hear it at that level. If the THD for a given output is 10% like some amps have it will sound like crap when you turn it up.

Lastly, make sure you use quality wiring for everything. I'm not going to say you need to run Monster cable. Heck, I think the stuff is a bit of a rip of, but run quality stuff. More strands of wire in a given gauge are good. Size the wire appropriately for the run you have to make and make sure you have a good ground. Lots of people end up putting a capacitor in their car to fix dimming headlights when all they really need is a 4 gauge grounding strap from the battery to the body. Good wiring DOES make a difference.

If you have any more questions or need a drawing I'd be more than happy to lay something out for you. :D

swinada 08-14-2007 01:57 AM

Re: Stereo sound system ???
thank you experience for that lengthy reply. Had to print it and add it to my overflowing Bus folder. Should have asked this questions a while ago before I started getting stuff ready. I wasnt planning on any AMP or Sub or anything till I remebered that SUB sitting around somewhere.
The thing is I got most of the stuff I wanted to reuse in the bus. Which is:
Head unit Innovatek DVD990 (Iknow you said good brand name and not cheap chinese stuff, but that is what I got laying around)
CAR In-dash DVD with 3.5" Wide TFT Colour LCD Screen
-Support USB & MMC/SD Memory Card for direct playback
-NTSC TV Tuner Receiver
-Electronic Anti-Shock
-NTSC/PAL Compatible
-2 Pairs RCA Output
-Repeat/Program/Random/Intro Play
-AM/FM/MPX Stereo Receiver
-30 Preset Stations
-Auto Memory Store/Preset Scan
-Preset EQ (Pop/Rock/Classic)
-4X60 W Max. High Power Output

I know it probably does not even put half of that 4x60 out

For speakers I got 6 Blaupunkt OEM 75W speakers and 6 OEM speakers out of a 1994 Ford Van.

I figured that head unit and the OEM speakers would do.Is it even possible to hook an AMP in to these speakers, or is it just a waste of money since the speakers are not of any great quality? I dont have the money to go and buy brand new quality speakers. I wouldnt even know what to look for if I bought on e-bay.
For AMP I was just looking at some cheap e-bay stuff too.
Four Channel Amplification
4x75 WattsTotal Output @ 4 Ohms
Variable Gain Control/Remote Turn On/Off
4 Ohm Speaker Impedance
Built-in Bass and Treble Control
Gold Plated RCA Low Level Inputs
S/N Ratio: Greater Than 85dB
Frequency Response: 15-30k Hz
Overload/Thermal/Short Circuit Protection
Power On LED Indicator
Automotive Type Fuse Protection
Dimensions: 9.05''W x 2.32''H x 10.63''D

sorry for the long post.

the_experience03 08-14-2007 11:21 AM

Re: Stereo sound system ???
That head unit will work fine! It doesn't have a subwoofer output, but never can use the rear RCA output through a low pass filter and into the amp. Heck, many sub amps have one built in. That's down the road anyway.

Ok, onward now to the speakers. Blaupunkt is that name brand stuff I was talking about. I didn't say you had to spend a lot of money...just that you want to get something from a company you can chase down. :wink:

Personally, I wouldn't bother with the OEM Ford speakers. Later model stuff is ok, but anything not built in the last 5 years is going to die a painful death even when only fed the power of a head unit. My factory Toyota headunit put out 4 watts by 4 channels RMS. My aftermarket headunit puts out ~24 watts by 4 channels after some tweaking to the board inside it. That's a big jump! does one go about wiring what you have? With the speakers like you have an amplifier will be a GOOD idea. Otherwise you will never realize their full potential. I have seen Pyramid amplifiers works rather well, but they keep their specifications rather hazy on purpose. Notice how it says 75x4 total output? That's that struck by lightning figure I was referring to in my earlier post. I would venture to guess your headunit has more power.

I COMPLETELY understand what you mean about not wanting to spend money. Here is my recommendation. Look for a tested, but used 4 channel amp on eBay, craiglist, the local college's free classifieds....whatever! I have had good luck with my used stuff. If they don't offer a DOA guarantee then I wouldn't bother, but deals can be had.

Ok, now for how to actually wire those things. You have two choices. One would be to use the single 4 channel amp. The other would be to use the 4 channel AND the sub amp. I'll start with just using the 4 channel.

After running the power, ground, remote turn on, and RCA wires to the amplifier you should just be left with the 4 channels of output. We are going to load that amp up, but in a good way. Without knowing where you want the most music power I'm going to have to keep this somewhat generic, but you'll get the idea.

When you connect the speakers you will have 1 pair on 1 output of the amplifier loading the section to 4 ohms. You will then have two sets of pairs on the other channel (4 speakers total, two to each output). That will load that other half of the amp down to 2 ohms stereo, a reasonable load by any means. You will have to decide where you want more power. The 4 speakers are going to be louder than the two even though each individual speaker will be receiving slightly less power. Put them in the loud section.

The single pair can just be directly wired to the amplifier. Just match left with left, right with right, positive with positive, and negative with negative. Simple!

The pair 'o pairs will be wired in a similar fashion. Run a set of positive and negative wires from the outputs to the left and right sides respectively. But here is where the tricks come into play. At the fasteon (female spade) connecter at the speaker you will have the wires from the amplifier. You will also shove another set of wires in there which will go to the second speaker on each side. Wire those to the positive and negative sides of the second speaker just like the first. The speakers are now in parallel and acting as a single 2 ohm speaker instead of a single 4 ohm speaker.

So...amplifier output now. The single pair will be running at the rated 4 ohms stereo output. The pair 'o pairs will be running at the same rate at the 2 ohm stereo/4 ohm mono rate. For instance...if the amplifier is rated to put out 75x2@4 ohms stereo (RMS, mind you) then it will probably do something like 220x1@ 4 ohms mono which equates to 110x2@2 ohms stereo (the way you are wired). Now divide that 110 watts by 2 since you have two speakers on each output and you get 55 watts RMS to each speaker. Alternatively you could just divide the mono rating by 4. I just want you to see where that number comes from...division of two because we're going stereo and division of two because there are two speakers on each side.

55 watts to 4 speakers > 75 watts to 2 speakers in terms of brute loudness.

The best part is that you will still have stereo sound and a working fader to balance the sound so long as you run an RCA pair from both the front and rear outputs of the headunit!

If you choose to run the sub amp in there as well you will just directly wire each pair of speakers to an amp terminal since you will have a total of 6 outputs. The RCA patch cables will run with one set to the two channel amp and another set to a splitter feeding all 4 RCA inputs of the 4 channel amp. In essence you will have three 2 channel amps then.

I hope that helps. The math has the potential to be daunting, but really isn't. If you have anymore questions just post up and I will try to answer them for you.

swinada 08-16-2007 10:27 PM

Re: Stereo sound system ???
experience, sorry to bother you again. I was looking around on e-bay and found this Pioneer AMP.

PIONEER GM6200F (GM6200)

600 Watts Maximum Output
Continuous power:
60 Watts x 4 (4 Ohm)
75 Watts x 4 (2 Ohm)
150 Watts x 2 (4 Ohm)
HPF/LPF 80Hz (-12dB / Octave)
Bass Boost 50Hz (0 / 6 / 12dB)
RCA Output (Pass Thru)
Speaker Level Input
4 Ohm Mono Stable
Cast Aluminum Heatsink
Oversized Power Terminals
Input Level (200mV—6.5mV)
it states "RCA Output (Pass thru)", does that mean I could run the RCA cables from this AMP tp the SUB -Amp input?? or what is that pass through used for?

Pioneer is a good brand name isnt it?

the_experience03 08-17-2007 11:25 AM

Re: Stereo sound system ???

Originally Posted by swinada
experience, sorry to bother you again. I was looking around on e-bay and found this Pioneer AMP.

it states "RCA Output (Pass thru)", does that mean I could run the RCA cables from this AMP tp the SUB -Amp input?? or what is that pass through used for?

Pioneer is a good brand name isnt it?

1. It is no bother. I enjoy the exchange of information on this site.

2. Yes, that RCA output means you can daisy chain amplifiers together. From the head unit you will still want to run the RCA output as the "rear" instead of a non-fading or subwoofer setting. You're going to have to control the subwoofer's level at its amp along with the low pass crossover, but that's no big deal at all (I've done it). You can also put a toggle switch on the remote turn on wire (the little blue one usually) for the sub amp (or both really) and turn them on individually for softer music if you please.

3. I have a lot of Pioneer stuff. My newest pioneer amplifier is sitting out in the garage and is a GMX-552. For a while Pioneer's quality and features went down as well as their price, no doubt in an effort to keep competitive in the entry to midrange level. Their sales also went down and their warranty claims went up. Since then (last 2-3 years) the quality has gone back up a lot and they've put the features that matter back in (like those RCA pass throughs) and I would run the stuff again in a heartbeat. The new headunits have AMAZING features and are so much cheaper than they used to be. The speakers also impress me a lot, especially given their price.

boojiewoojie 08-19-2007 04:25 PM

Re: Stereo sound system ???
I've been reading the good posts here and just thought I'd throw in my 2 cents. Check out Parts Express for buyout items. I have a wholesale account so I'm not sure if the prices are exact, but check out something like Part Number 269-326, a buyout 5 1/4 and silk dome tweeter, with 2nd order xover for $3.98 each. Those will probably give you some really good sounds. The speakers are the most critical part of how it's gonna sound. I would consider going more toward home speakers since they would physically be easier to integrate into the bus and will give a better sound. You can buy prebuilt small bookshelf speakers like Part Number 302-019 or even a kit like Part Number 300-640. Look at Jake's bus- he put small bookshelf speakers in the compartment above the driver, which probably sounds great. You could even look at "ceiling speakers". There are some nice sounding units that are pretty cheap. The very cheapest way to go speaker wise (other than junk yard finds) is to buy the components and build your own. I haven't put speakers in yet, but one thing I've thought about is replacing the door in the top compartment w/ plywood, cutting out for stereo speakers and mounting the x-over components on the backside. Anyway, a whole lot of ways to go about it.

swinada 04-21-2009 02:06 AM

Re: Stereo sound system ???
well it has been almost 2 years since this thread was started and I still dont have my stereo system hooked up. Still listening to the old boombox while working in the bus. But since there is so much good information here thanks to Experience I'll bring this post back up to the front and add a coupple questions. :)

I got my Blaupunkt speakers (6) and a couple other ones. Plus I bought a Sony Amp Xplod XM554Z cheap 4 channel unit.
today I was actualy starting to wire some things in for the sound and of course a couple more questions popped in to my head.
I was planing to mount the amp above the windshield in the cubby hole somewhat like this.

but the question that popped in to my head was with all that other wiring up there, lights and such, and Antennacable for 2 way radio as well as FM radio, will the AMP cause any interference? Would it better be mounted away from all that cabeling somewhere on the ground or does it not really madder? If I can mount it up there it would safe me quite a few meters of cabeling it also would be most central to get equel lenghts on both sides to the speakers.

the_experience03 04-21-2009 08:54 AM

Re: Stereo sound system ???
I really don't think you'll have any interference problems. The biggest thing is to keep power wires away from sensor wiring on fuel injected vehicles because the magnetic induction will give your PCM some crazy readings. You don't have to worry about that. :lol: If possible try and run the RCA and power wire apart somewhat as it is possible to get a little noise from that, but it's been my experience that almost all noises in stereos are caused by the ground side of things. The only thing you can do is try. If you get noise that sounds like you're playing Excitebike we'll go from there.

NewSkewlHauler 04-21-2009 09:19 AM

Re: Stereo sound system ???
If you get noise that sounds like you're playing Excitebike we'll go from there.I loved that game!

Redbear 04-21-2009 06:17 PM

Re: Stereo sound system ???
If the ground is bad on the 2-way radio antenna, or the antenna is very badly tuned to the frequency band (wrong length whip or wrong coil, if needed), some of the energy during transmitting may come back down the outside of the antenna cable and cause a hum in the speakers and possibly absence of music. The hum could occur any time the amp is powered, even if the music source is off.

swhite832 04-22-2009 07:08 AM

Re: Stereo sound system ???
I have installed a couple of stereo systems in boats which take alot of abuse. As Experience has pointed out, it is very easy. If you can swing it, buy a new head unit, three preouts is the way to go. A problem I had on the boat with only two preouts is I had to choose on the amp which channel it was getting the bass signal from(front or rear). I had to have the fader option to switch between the tower speakers and interior boat speakers. I would lose alot of my bass upon going from front to rear(Experience, if there is a way around this, please advise) . At any rate the speakers I have used in all my applications(two boats, hunting vehicle, and will use in bus are Infiniti 6022i. These speakers have gotten wet. They have had constant exposure to the elements and still sound better than average. The plus is they cost about $56/pair on Ebay.

swinada 05-08-2009 11:10 PM

Re: Stereo sound system ???
surfing on the web i found this site, has some good drawings on how to wire a stereo system with dual batteries, isolater or solenoid. Applicable to bus wiring too for back up batteries. Check it out

SmartBusRob 03-27-2018 10:50 AM


Originally Posted by Steve (Post 15681)
I have a massive sound system in my bus, way to complicated than you would want [emoji38]

I'm super interested actually lol... I'm mapping out the sound system for the driving area to have optimal sound while driving and I'm planning a seperate system for the entertainment center I'm planning for the living area.

Trying to figure out how to optimize the audio.

Sent from my SM-G950U using Tapatalk

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