School me on some car audio basics, please.

[kishy]

For a little more info... the eXcelon amps in mine are rated at 22 watts rms and they get plenty loud for me. Since I have no idea about the amp in the Blaupunkt, I don't know if it'll clip like that Pioneer I put in the Mark VI does. Looks like the Pioneer you have in the list is the same basic ratings as my eXcelon, so it might drive the Kenwoods a little better than the Blaupunkt. Obviously, testing that for yourself would be the real decider.

How much of a gap in rating needs to exist before clipping is a risk?
I'm assuming that's something along the lines of a speaker pulling more current than the deck can provide, and the deck's built in amplifier cuts out as a protection feature? Or if not as a protection feature, simply due to failing to keep up with the demand?

I'm assuming that,

• if ratings are close together/well matched, clipping either won't happen at all, or only happen at very high volume during a time when a lot of sound is being produced
• the wider the gap in rating (e.g. 100W speaker and 20W deck vs 30W speaker and 20W deck), the lower in volume level the clipping would begin

Or am I way off here?

The Pioneer I listed, I actually have two of. One in the 83 MGM, one in the Ranger. It has very close to the right green for Ford stuff and it has front panel 3.5 in, so although it doesn't have the desired looks, it does hit some requirements. I probably wouldn't bother to spend money to replace it if I can build something decent around it.

The 83 is a less-ideal case study, as a car. It is a 4-speaker car, does not have door speakers. Cutting the door cards isn't really something I'm super interested in doing. Making a decent result using just speakers in the dash and package shelf would be nice.

[sly]

Clipping is an issue with amplifier design. Many amplifiers are rated on peak values and typically 80-85% of that is actual peak without clipping. Some bad designs are more towards 60-70%. Most major brands fall into the 85% area. So with speakers rated at 30W, being able to drive them at 80% will get you well into the 120db range typically so 50% should be at least in the 85db range from my experience with these budget type setups.

It is better to match RMS values as close as possible and ignore peak values since those are pretty much meaningless in the grand scheme of things. But I haven't found any 20W RMS speakers that are worth dealing with that don't cost over $200 a pair, so I deal with the mainstream types. A spread of 30% below 50W is fine. Would be better to be closer, but it will definitely work. And it's always better for the speaker to have the higher power rating. Less chance of blowing up stuff. My subs are a good example. Amp is rated at 130W RMS and the speaker at 135W RMS. Peak values are way out there at 800 and 350... but the amp rating is in bridged mode (stereo to mono) and I never use that mode.

in short... 30W speakers will do fine even on 15W of clean drive for casual listening unless you're on a grooved highway with huge amounts of road noise.Then you may need to push to possible clipping territory. Clipping can be reduced by lowing the bass since it's the big power hits that cause the clipping since the capacitors aren't large enough to fully sustain the amp's power rating if it's clipping.

I've seen good sound from Sony speakers, but I've never used them personally. I've also seen good things from Kicker. But that was mainly low end augmentation of a setup that has good highs and mids already. And yeah, just add decent speakers to the vehicles with the Pioneer units and you'll probably be fine.

[DerekTheGreat]

edit: replied at same time as you Derek, reviewing your post, but wrote the below first.

So, what should I be looking for in a speaker to attach to the following options:

• The factory premium non-JBL system
• Blaupunkt Milano with the factory amplifier present
• Blaupunkt Milano with no external amplifier
• Pioneer DEH-1900MP with no external amplifier

Is there a wattage+impedence+decibel range that covers all of these applications?

Just picking some favourably priced examples, what do we think of

• these as door speakers: https://www.crutchfield.com/p_113136...6S.html?tp=105
• these as package shelf speakers: https://www.crutchfield.com/p_113C68...6S.html?tp=105
• not even sure what to look at as dash speakers due to the weird size, what about these: https://www.crutchfield.com/p_236TER...r35.html?tp=10

The Kenwood KFC-1366S has a lousy sensitivity rating of 89dB, the second Kenwood's are nearly identical at 90 and the MTX's are the worst at 86. That's a big enough gap such that if you paired those MTX's with either Kenwood, you'd notice the Kennies playing louder over the MTX's. Also kind of why speaker matching is important, at least in the sensitivity and impedance department.

Anything with an external aftermarket amp should play fine with any of those modern speakers rated at 2 ohms. A factory amplifier might have some issues with them at higher SPL's due to the extra current draw. You might end up blowing the fuse for the amplifier, running it hotter and also if it's tied to the same circuit as the radio, you might see the lights flicker. That is unfortunately a case by case basis. For example, I had to put a CDM (the amplifier section of GM truck radios from 1988-1994) from a 1994 GMT400 in my K1500 as GM redesigned it for that year. It's got stouter heat sinks and more magic smoke inside, so it handles those Infinity plate 4x6's I put in it much nicer than the period correct CDM. What that means is it sounds a bit nicer, doesn't break-up as quickly and the radio's display doesn't dim as much as it did before with the old CDM.

I'm glad sly pointed out the RMS rating of the one amp, 22 watts RMS. When I bought my first couple radios, I spent extra money getting the ones rated above 20 watts RMS because I thought it made a significant difference and (unbeknownst to me at the time) would give me better headroom. Well, if we go back and look at the numbers for wattage & SPL output, you'll find a 22 watt RMS amp is no better than a 16 watt RMS amplifier. Market-wank-a-teering, all that is. Most audioholics measure headroom in dB, and they tend to want 6 dB of coverage. Doesn't seem like a lot, but it is depending on your average listening needs. Let's say you went through all the trouble setting up your high pass filters right and find your system is comfortable producing SPL's on average of 105 dB. However, to make it interesting, let's say you got there with those awful 86dB efficient MTX speakers.:

1w rms= 86dB, 2w=89dB, 4w= 92dB, 8w= 95dB, 16w= 98dB, 32w= 102dB, 62w=105dB, Damn, nearly100 watts RMS needed just to achieve 105dB with those skag-nasties.

..So you want 6dB of headroom? You need to take that last power figure and double it, so 250 watts RMS per channel is what you'd need to comfortably drive those crap-tastic MTX's. But they're only rated for 20 watts. So now you can see how that speaker really blows. By the specs, it's only going to be comfortable pushing 99 to 102dB. Don't worry too much about a speaker's max RMS watt rating. You'll be more likely to blow a speaker by underpowering it than you will by overpowering it. Amplifiers that clip essentially send square waves to the speaker when they should be receiving sine waves. When you feed a speaker a square wave, that'll overheat the voice coil and that's where you run the risk of blowing them up. Of course, you can do the same to cheap materials by overpowering them as well, it's just not as likely due to peak wattage figures happening infrequently and average RMS values being much lower.

[gadget73]

the whole clipping melting speakers thing is not as much of a problem as people make it out to be. By the time its doing that it sounds so god-awful that anyone with ears that work will turn it down. if your ears don't work you probably won't notice the tweeter being fried anyway so ultimately it doesn't matter.

[sly]

Yeah... this is why I try to match nominal (RMS) power per channel/speaker. This is mainly for durability as you're not going to blow up speakers if you can't overdrive them. I know audiophiles tend to like to get amps way over the ratings of the speakers so they can drive them with ease for the most efficiency and clarity in sound reproduction and are very careful to always turn the volume down after listening to something, but I don't care if I have a little hiss when I crank it up. When I want it loud, I just want the neighbors to enjoy it too... without clipping.

[DerekTheGreat]

the whole clipping melting speakers thing is not as much of a problem as people make it out to be. By the time its doing that it sounds so god-awful that anyone with ears that work will turn it down. if your ears don't work you probably won't notice the tweeter being fried anyway so ultimately it doesn't matter.

Not quite. If you've reached the point it starts to sound that bad, you are REALLY clipping the amplifier. This is the reason I will not buy amplifiers for my main listening system upstairs if they do not have clip lights. Big fan of Crown, but can't vouch for anything of theirs that is super modern. I am running a Studio Reference I and II.

Yeah... this is why I try to match nominal (RMS) power per channel/speaker. This is mainly for durability as you're not going to blow up speakers if you can't overdrive them. I know audiophiles tend to like to get amps way over the ratings of the speakers so they can drive them with ease for the most efficiency and clarity in sound reproduction and are very careful to always turn the volume down after listening to something, but I don't care if I have a little hiss when I crank it up. When I want it loud, I just want the neighbors to enjoy it too... without clipping.

The hiss is generally a byproduct of your components' Signal to Noise Ratio or Hum & Noise, the higher the better. My general rule of thumb is not to buy anything with a SNR of <100 dB. They'll always hiss some what- hell, most material recorded before the digital era already hisses to beat the band. Yay tapes! The intro to "Immigrant Song" by Led Zepplin is about as awful as it gets. Anyway, Crosstalk is another one, which is why a lot of audiophiles move to mono amplifiers for each channel they want to drive. Cross talk is essentially when the left channel's signal bleeds into the right and vice versa. Stereo separation/presentation is improved immensely by moving to monoblocks or amplifiers with that rating at or above 100 dB. Of course, bridging an amplifier effectively makes it a mono block and thus enables you to throw that rating out the window.

As for blowing speakers, I like to take the max RMS power rating of a given speaker, multiply that by three and then use the result to determine how much power I need to effectively drive said speaker. Of course, none of that matters if all you want to do is casually listen. But if you're going to jam like I do, that's a good practice to follow. For example, I had and still have a set of JBL LX44's. Their maximum power rating is 125 watts. Pssh, I fed them nearly 400 and they rocked like they never had before without even bottoming a woofer. I didn't run a high pass filter on 'em when I did that either, I was really impressed. Again, you're more likely to blow a speaker by underpowering it than you are by overpowering it. Also, just because you have 400 watts or more available, doesn't mean you're using them. What you're actually using at a given SPL is approximate to those rudimentary calculations I posted earlier. When you think about it, it's kind of like horsepower.

[sly]

True enough. Though all amps have hiss if you push them far enough (learned that from an audiophile amp producer) which is why more power on the amp and less on the speakers for audiophile systems. The better ones just don't show it until you're at ear melting levels and it's still less than the stuff I use. I am pretty much the definition of the casual listener. I want it to last a long time and don't get affected by me being silly with it. And when I say blowing speakers, I mean literally forcing voice coils out of the cones (seen a few folks pull this off pushing 5-10x the power through speakers) or fusing wires in a flash by overpowering them. Underpowering them and current melting the wires together is a different story. I've never had that failure because I keep my stuff close to, if not matched. I've also never blown a cone out either. I've had surrounds disintegrate from age though. I did fix my mom's old Fisher tower speakers from cat scratch damage. Still running strong after 40 years. And as much of a bass head as I am, I still try to balance my lows with the ability of the system to produce the highs.