I have reservations about the 2" headrest speakers with that setup, having near-field and distant sound sources, ahem, sounds like a recipe for weird phase effects and off axis responses as you drive.
I think the best idea, though expensive, is to buy a reproduction door panel and put the largest speaker you can fit in there. If this is too expensive, how about trying to make your own door panel? You could then fit something like the Focal ISS 8" shallow component set, in an MG it would sound great and you wouldn't need a sub.
Slightly less involved would be to build a tuned enclosure for the 5.25" in the rear and leave the speakers at that.
A good set of high power speakers, I am partial to the JL C5 series, and a tiny hidden full range class D amplifier and you would have a good clear system coming from behind; old school sound system for an old school car. I wouldn't trust the 55w rating of the head unit, more likely to be around 10 clean watts.
I think the best idea, though expensive, is to buy a reproduction door panel and put the largest speaker you can fit in there. If this is too expensive, how about trying to make your own door panel? You could then fit something like the Focal ISS 8" shallow component set, in an MG it would sound great and you wouldn't need a sub.
Slightly less involved would be to build a tuned enclosure for the 5.25" in the rear and leave the speakers at that.
A good set of high power speakers, I am partial to the JL C5 series, and a tiny hidden full range class D amplifier and you would have a good clear system coming from behind; old school sound system for an old school car. I wouldn't trust the 55w rating of the head unit, more likely to be around 10 clean watts.
I mentioned that earlier, not sure if he read it however.
To reiterate, a 12v head unit is capped at 10-12 watts by reasons of physics, and will be practically usable only when the car is turned off.
I have installed headrest speakers 4 times, one of them in a stereo show car. The show car is the only 1 installed with a channel per headrest because we didn’t care how it sounded in the car. Look under cars with factory headrest speakers, all the ones I know run a stereo pair per headrest. Why? An un-summed mono channel behind your ears gives you the worst sound quality. If you think about stereo separation factors in a small car, unequal distance, off axis the interior volume....stereo spereation would only be possible in a car like this if the interior was designed around the stereo and even then would only be noticeable at low volume. Lucky this is just a wiring choice, hook it up and test it both ways, you’ll see what I mean.
If your dash is not vented on top and the center console is out you could put 2 auras facing down (toward the floor) under the dash. This would be my last choice for placement but it will work...the front speakers are ultimately optional, all the boogie in the back might not bother you at all.
Quite the opposite in the cars with headrest speakers I've had. And they truly help when the top is down and you're cruising at highway speeds. The headrest speakers give you the detail and presence that is gone with the wind. 🙂
Stereo is good. Don't remember about mono.
You can get about 20w RMS from an amplifier powered from a 12v charging system when driving 4 ohms.
13v peak = 9.2v RMS
9.2^2 = 84.5
84.5/4 = 21w RMS
13v peak = 9.2v RMS
9.2^2 = 84.5
84.5/4 = 21w RMS
Lmao so did I imagine the running 550 watts in 1 ohm stereo to 4 8” woofers or where they just 20 really big watts? The charging system does usually make it 13.5-14.5v, maybe that’s where the extra 530 watts came from? This was back in the before time...before huge caps and multiple batteries where common. Damn I wonder were I was hiding the 230v generator?
I followed your math 13vrms@1ohm should still only be producing what 170 watts right? Where do the dbs come from then? Got to find that generator....
Well ok I mostly ran a 60 amp fuse (which blow all the time) so depending on true voltage maybe 475-500 watts/channel
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Perry's right on as always.
Most amplifiers have a SMPS to raise available voltage to the amplifier stages.
Most head units don't.
Most amplifiers have a SMPS to raise available voltage to the amplifier stages.
Most head units don't.
I’m not sure about mono, I agree that stereo is good and hence my deep suspicion of the mono near field, stereo wide field ( if that’s what it’s called idea) . 😀
Of course, this is an assumption I mostly agree but calling it physics and saying it cannot be done is just not correct. If someone who didn’t know read that they would have a misconception, which they believe is supported by physics, about wattage limitations in 12v...I haven’t looked very far into car head units for years but I know they are using larger fuses these days, this could already be an outdated assumption.
Sony mex xb100bt, 100 watt x 4 with bridgeable channels, a Sony not exotic, available everywhere...many home audio physics (or assumptions) go sideways when applied to 12v-15v dc...we have proven many things we call laws are not absolutes and calling that 12v physics is still misleading, even if technically correct in a vacuum it is not supported by reality.
The Sony mex xb100bt uses an IC that the datasheet rates at 28W into 4 ohms at 14.4v and 20% THD. The higher power rating is only when a charge pump produces higher voltage.
Amplifiers in systems that produce 155dB don't have their audio circuits running off of a 12v supply. Some of the rail voltages (produced by switching power supplies) are more than 400v.
Might I suggest we stick to discussing the specific equipment the OP has listed?
The pedantry and reductio ad absurdum is doing absolute nothing to help the OP on his audio quest.
The pedantry and reductio ad absurdum is doing absolute nothing to help the OP on his audio quest.
Sorry, I mentioned the advantage of a step-up power supply as is provided in most component amplifiers in post 25, but didn’t make any diagrams that would spell it out for you.