Appartently FAILED Vehicle Audio 101 - Any more tips?

Here is my original post: Fairing Radio Shell Audio Help Request

Brief summary:
CHEAP radio and amp
Mid priced good brand 135W 2-way 4inch speakers
radio/speaker shell stuffed with memory foam for now
speakers distort at higher volumes and not very audio at decent speeds
4 different size bass blockers NOW available - only tested 1.2Khz so far (received today: 300, 600, 800hz).

Now for my new problem:
I installed 2 more identical 4" speakers into my (30 year old) hard plastic saddlebags.
Saddle bag doors closed - can barely hear speakers (with front speakers faded out).
Saddle bag doors wide open - significantly louder and more bass.
Saddle bags are about 18"x12"x8 (didn't actually measure for this post)
I currently have radio's balance wired as front/rear fade (like I said CHEAP radio).
If I give the front speakers about 10% fade the speakers about about even in volume. Anything above that and I basically can't hear the rear speakers.

So besides the $$ and time spent, I'm definitely annoyed that I drilled 4" holes into my Vintage saddlebags and I can't really hear them.

What can I do or do I NEED to do to make this 4 speaker setup work? I don't need perfect volume/bass balance but I wanted it somewhat better.

At this point I can't buy a real radio and amp, but I'll keep it in mind...

Speaker cones?
Audio mat material inside bags?
Swap speakers to make sure the "newer" speakers aren't defective? (seems unlikely).
Build a mini sub-like box inside my saddle bags? How big? I do use my bags for storage...

I'm off for a 3 day ride/event/camping party, but this problem is going to bug me the whole weekend, especially while riding. I'll be checking the forums on my phone so any feedback would make me feel a little less annoyed.

 

you sure sure the rear speakers are wired correctly? the may be reversed and canceling each other out.

 

Hi, I've done alot of audio in the past so let's see if I can help. 4" speakers are small and the cones don't have that much travel distance available to them to produce the bass. What I think is happening is that since they are not in a sealed box there is no pressure behind the speaker to control it's travel which makes the speaker cone material flex too much and distort. I think you would get better sound if you mounted them in some kind of sealed box (you can get the dimensions of the boxes off of an audio web site, you just have to input some specs from your speakers). I would try that and you might be surprised what kind of sound you get out of a good quality speaker. You may be able to use them full range and not limit yourself with the bass blockers and get better sound.

 

I think there'sa reason why you never see bikes with 4 speaker setups. You won't hear the rear speakers for !@#$ once you're at normal riding speed.

1.) Your helmet is gunna block alot (if you wear one that covers your ears)
2.) Sound waves don't like to travel against air moving at <insert speed here>

You will be better off with a 2 speaker, in dash setup, and have it cranked most of the time your riding. Any bike i've ever seen with a radio in it, the owner has it absolutely blasting so he/she can hear it.

 

Fyi I can barely hear rear speakers with engine off. :-(

Also plenty of baggers with rear speakers. I'm just trying it the homemade way.

I'm gonna pull out the speakers and make sure the are good outside of the bags...

 

I've worked with audio professionally. I can probably help.

It's a good thing I read your other post!
Are you still using the head unit (radio) amplifier, or are you using your new amplifier? I couldn't tell. Did you fix your bitrate problem? That's a biggie for what you're trying to do. Also, how do you have your amp wired, like what is hooked up to what? If it's wired less than optimally, it'll make a HUGE difference. Go ahead an put the gain on your amp all the way up, you want your gain structure to be controlled by the low power head unit (what you've been calling radio, but it's more like a mixer, and is called a head unit in this application to avoid confusion with an actual FM radio). Of course turn your head unit volume all the way down!

You can overpower your speakers all you want...as long as you don't crank the volume up so loud that the cone pushes past the spider (wavy thing on the back). But running too low is like putting a lawnmower engine in a semi truck, it's not going to respond very well!

Once you answer the above questions, we'll try running your front and rear speakers in series and using the 2 OHM setting on your amp. That will give you more power than running them in parallel, which halves the power you were already getting.

Don't use the 1.2kHz high pass filters, for 4" speakers I'd go with the 800Hz max, and probably the 600 Hz would be best. Keep in mind though, you are actually reducing the power if you are putting something inline between the amp and the speaker. You ideally want your band filtering before the amp, which requires a different piece of equipment, though some amps have them built in. If you are using MP3's, that's already done for you, so I wouldn't even put any high pass filter in.

If the apparent loudness improves when the saddle bags are open, you have a acoustic issue. That's hard to diagnose without being there, but it might not be that big an issue if you get your setup right. It might just be that more sound gets out when the bags are open because both sides are open to the air, not due to a damping effect of the bag.

 

Same crap hu and amp via RCA output.

Currently using only 2 RCA inputs of amp. Didn't seem to mater with w speaker setup. All 4 wire sets were driving the speakers.

Amp has 4 pairs of wired outputs. I was trying to use all 4.

I grabbed a bunch of 320 mp3 for the weekend.

The SD card is way quieter than fm or aux 1/8 input (ie iPod).

I did Max out amp this weekend. With Max and bass blockers I had some issues. So I took off blockers. I can hear fronts OK if its not to windy. (70mph and strong with sucks).

I have time to work on rear aucoustics since I already drill the holes. I guess I have to figure out power output (before better hu and amp).

 

If you can hear the fronts ok, but not the rear (assuming you aren't moving) then try some acoustic solutions. Maybe look at another bagger to see if there is a little box that houses the speaker. I'm sure you don't want to fill your bag up with foam just for some sound.

You should be getting the same power if you are using the 4 channel amp to 4 identical speakers.

Again, make sure all the +'s match up with +'s and the -'s match up with -'s.

 

...uhh... You really shouldn't mismatch impedance settings on amps with what you're driving. Unless you like to see the magical smoke that makes your stuff run escape your amp.

As impedance increases, power decreases, but ONLY with the same impedance on the outs, as the amp expects to see. Running 16 ohms of load on an amp set to see 2 ohm's will make the power output seem VERY low, not so bad for the amp, but not really how you want to wire it up.

DO NOT try to run say a 2 ohm load on an amp set to see 16 ohms. You WILL fry something (amp or speakers).

I've done car audio for many many years, I also work in a music store that rents PA gear and have these questions come up all the time.

I've seen a customer hook a 100W Marshall head to a 4ohm cab, plug into the 16 ohm output and pretty much drop the guitar and run out the store when they turn it on.

I'll have to review your other thread and get caught up on this

 

8)
I guess you didn't read that his amp is 2 ohm capable.

Good general warning anyways, thanks for educating the forum.

 

The amp CLAIMS to be 2amp capable...

95-100F out this week. In no hurry to test anything yet...

 

A completely different approach would be to put some quality headphone speakers inside the helmet. Excellent stereo separation and clarity without an amp. Combine with a bike-to-bike intercom system so Cops can't say anything about it.

 

If I had the $$ in one lump sum I would already have a pair of Bluetooth helmet headset and using my phone + Pandora or mp3s.

Regardless I'll figure out the speakers and eventually get helmet set as well.

 

Doesn't make a wink of difference if the amp can do 2Ω stable. If you're trying to run that into a 16Ω load, it'll sound like kaka

Now if you're running front and back (say left side only) 4Ω speakers in parallel. that would be perfect (4+4 in parallel = 2) again pending the amp can do 2Ω stable.

 

It is a bit wet out for me to do anything at the moment...

Do you suggest I try wiring the rear speakers in parallel or series to see if it's any better without acoustic improvements?

The amp does have 4 sets of speaker wire outputs, so I have been using all 4 when testing.

When I got a chance I was going to put a "Tupperware" bowl behind the speakers to see if it made any improvements, and if I'd need to work on building a mini box inside the saddle bag.

 

No, the best way for you to wire your amp is the way you did it. There are four speaker channel outputs and four speakers, you can't decrease the resistance of the speaker individually, and using less channels would be wasting available power on the amp, so you have it the best way.


Just to be clear, series is when it is wired up amp+-speaker+-speaker+-amp, all in a series. To calculate the total resistance you use the formula 1/Rt=1/r1 + 1/r2 + 1/r3...etc....so two 4 ohm speakers in series would be 1/4 + 1/4 = 1/2, since it's 1/Rt the Rt=2.

Parallel is when you connect amp++speaker+speaker and then amp--speaker-speaker, kind of hard to show like this but the amp's + goes to all the speaker +'s and the like for the -'s. To calculate the resistance for parallel you just add the resistances, Rt=R1+R2+R3 etc, so two 4 ohm speakers in parallel would total 4+4= 8 ohms of resistance.

If you can, you can try switching the front and rear amp leads from the amp first, then maybe even to the amp, to see if one of your sets of channels is bad.

But like I said, if it sounds fine when the speaker is in one physical spot but not the other, it's probably acoustical, not electronic. You can test that by putting the rear speakers, wired the same way they are now, into the front pockets that you know are just fine.

Also...with audio especially, you pay for what you get. Build quality makes a HUGE difference. And if you are combining Pyle amplifiers with pyle drivers and a cheap head unit and I don't know what you're playing MP3's on, but sometimes they don't put out much gain....well, those things can really add up to bad performance.

 

Definitely cheap Pyle headunit (and mp3 player via SD) and cheap Pyle amp. But decent quality Polk audio db401 2way 135w speakers (with nearly no bad reviews).

I can try physically swapping speakers front to back; I already tried swapping wire connections on the amp's input and output (quick connect bullets installed).

I'm going to tear off my backup fairing starting next week and install a painted one. I'll have lots of options and acces to radio shell during rebuild/reinstall.

 

Ok, I read the manual for your amp and looked up your speakers.

1st, your speakers should be receiving plenty of power...in fact they are overpowered by quite a bit. Like I said before, that's ok as long as you don't drive them do the point where you hear any distortion. At that point you are running the risk of burning the voice coil or breaking the spider. I'm a little concerned that you had them loud enough to hear on the freeway...you might want to check them out, push on the cone while looking for tears or cracks, and to see if the cone will even move.

2nd, be sure you have the input level set to RCA...NOT pushed in.

3rd Did you try that polarity switch? Polarity makes a big difference and a switch will let you hear the difference even better. If you don't know what that does just ask, but I'll leave it for now.

4th, try plugging your mp3 player straight into the input on the amp...it says it came with an adapter. If your head unit is your mp3 player try a different method.

Plus I want to double check what the problem now is...your fronts sound fine, no problems, but your rears have no volume, but they don't sound distorted, just not loud throughout the entire range of low to high?

 

Overpowered: yes if Pyle specs are not bs. I'll check for damage soon. Shell designed to be heard. Can get better pics next week.

RCA switched properly.

Polarity switch = basically no sound


Fm and input are much louder than sd mp3. IPod was acting up so limited testing. IPod is ideal source but not mounted securely yet.

Rear speakers work and cones move, but large hard thick plastic saddle bags seem to be eating up volume when closed. When open decent but not full volume coming out of door not so much the front of speaker (or so it seems).

Recap and current settings :
Amp gain Max
Amp volume knob Max
H.u. tone turned up (less bass) about 50%
320 mp3 when possible
Front speakers distort the sound less with amp maxed. H.u. volume kept under 75% at 70mph.
Rear speakers basically can't be heard with engine off even though they are pumping.
All wires properly matched + -
I wear a full face helmet with over 6 air inputs/vents

I may never hear rears on the highway but in my driveway I should...

 

Well....all I can say is that if you put your 2 rear speakers into the front spots and they work fine there then you have some weird acoustic issues.

The thing is, the highs shouldn't be affected by the enclosure. They might sound bad, but 1kHz and up should at least be pretty loud from 3 feet away no matter how it is mounted.

Since you mentioned it and now that I think about it, and doing some research (it's been awhile since I've worked with car audio), a 1x3x6 inch amp with a 10 amp fuse is NOT putting out 100w RMS at that price.

I'd return the head unit and the amp, keep the speakers, and get this, or something similar, for the same price.

20wx4 should be enough to get those polks under control.