Automotive style stereo/amp question

[seachicken]

Hey guys this is a question about automotive type stereos, I've installed my fair share but never with an amplifier... My boat has an Alpine stereo and Sony 1000 watt amp installed with the Memphis MXA60L marine speakers WITHOUT a subwoofer. The installation information I've found calls for a 50 amp fuse. I need to clean up wiring and on a 100 amp fuse block 50 takes up a lot of realistate and a significant wire size. Just wondering if an amp significantly improves sound quality on these speakers? Is it worth having the amp without a sub? Thanks.

 

[-Jim-]

I suggest you post model numbers for all the remaining gear, and what boat and where are the speakers installed in it. (In a Cabin or outside?)

From what I could find the MXA60L marine speakers are rated for 50 Watts RMS/ 100 watts Peak with Sensitivity at 88 dB but with no reference parameters, so take that for what it is. (To me it means they are not high efficiency but depending on the install it may not be too relevant. And the point of RGB LED lighting is lost on me for speakers.) They don't list frequency response but they are coaxial speakers.

Car Audio amplifier output numbers are usually just about the most bogus numbers on the planet. OEMs publish values dramatically higher (like 1,000 Watts) than they can achieve based on unusable distortion numbers that would clip / damage the speakers at even half the published value.

A lot of Alpine head units have built in amplification and Sub line outs. You may be able to get away from the Sony Amp, but without details requested above, we'd be guessing. Another big factor is the type of music, and volume levels you want to listen at. Loud with a lot of bass will cry out for a Sub and an amp to drive it.

I hope this is helpful.

 

[seachicken]

I suggest you post model numbers for all the remaining gear, and what boat and where are the speakers installed in it. (In a Cabin or outside?)

From what I could find the MXA60L marine speakers are rated for 50 Watts RMS/ 100 watts Peak with Sensitivity at 88 dB but with no reference parameters, so take that for what it is. (To me it means they are not high efficiency but depending on the install it may not be too relevant. And the point of RGB LED lighting is lost on me for speakers.) They don't list frequency response but they are coaxial speakers.

Car Audio amplifier output numbers are usually just about the most bogus numbers on the planet. OEMs publish values dramatically higher (like 1,000 Watts) than they can achieve based on unusable distortion numbers that would clip / damage the speakers at even half the published value.

A lot of Alpine head units have built in amplification and Sub line outs. You may be able to get away from the Sony Amp, but without details requested above, we'd be guessing. Another big factor is the type of music, and volume levels you want to listen at. Loud with a lot of bass will cry out for a Sub and an amp to drive it.

I hope this is helpful.

https://www.sony.com/lr/electronics/car-amplifiers/xm-n1004#

Thanks Jim, it's a Sony N1004 amp, boat is a 20' DE with an open cabin, 2 speakers in the front, 2 facing the back deck. Just want to listen to some rock music and still be able have a conversation. Certainly not looking to play music so every other boat in Georgia Straight can hear it. Is that amp overkill for those speakers? Only good thing I can say about the lights in the speakers is that it shows me the battery is still on. If it didn't come with the system installed I'd have been fine with a JBL speaker.

 

[brutus]

I have installed a pioneer sterio in mine without amp, with Amazon speakers,(cheap)4x two in the cab 2 outside, no amp, it’s loud enough that other boats can hear it, and not sucking to much juice. Not sure this is relevant lol.,oh I also hooked up my vhf to one of the speaker

 

[seachicken]

Oh that's a good idea about the VHF, hadn't thought about power draw either. I have no idea what amount of power amps draw with tunes set to a believable level. Thanks

 

[-Jim-]

The Sony's Specifications are 70W x 4 / 1.0% THD when driving 4 Ohms from 20 to 20,000 Hz which is a good fit for your speakers. (I'm guessing the Memphis MXA60Ls are 4 ohms as their site doesn't provide that info.) It does have both a Low Pass and a High Pass filter so you could hook up a stereo pair of speakers and a Subwoofer (minimum 4 ohms) to it as per the Manual.

However, as you don't have a Sub, and want to connect 4 Speakers, I'd suggest you enable the High Pass Filter (HPF) for both pairs of speakers. The HPF ensures that everything but the deepest bass notes are directed to your full-range speakers. I don't think they can reproduce much Bass below 80 Hz, and they will struggle in the attempt. You could see if turning it off or on (before energizing the amp) makes an audible difference at the volume levels you typically listen at.

Without the Alpine Head unit model number, I cannot investigate if you can run your system adequately without the Sony Amp. If you want my guidance, please supply that detail.

I hope this is helpful.

 

[seachicken]

The Sony's Specifications are 70W x 4 / 1.0% THD when driving 4 Ohms from 20 to 20,000 Hz which is a good fit for your speakers. (I'm guessing the Memphis MXA60Ls are 4 ohms as their site doesn't provide that info.) It does have both a Low Pass and a High Pass filter so you could hook up a stereo pair of speakers and a Subwoofer (minimum 4 ohms) to it as per the Manual.

However, as you don't have a Sub, and want to connect 4 Speakers, I'd suggest you enable the High Pass Filter (HPF) for both pairs of speakers. The HPF ensures that everything but the deepest bass notes are directed to your full-range speakers. I don't think they can reproduce much Bass below 80 Hz, and they will struggle in the attempt. You could see if turning it off or on (before energizing the amp) makes an audible difference at the volume levels you typically listen at.

Without the Alpine Head unit model number, I cannot investigate if you can run your system adequately without the Sony Amp. If you want my guidance, please supply that detail.

I hope this is helpful.

Ok thanks, I'm just on my way home from work, will be at the boat tomorrow and add that bit of information. Cheers!

 

[Rain City]

The Sony's Specifications are 70W x 4 / 1.0% THD when driving 4 Ohms from 20 to 20,000 Hz which is a good fit for your speakers. (I'm guessing the Memphis MXA60Ls are 4 ohms as their site doesn't provide that info.) It does have both a Low Pass and a High Pass filter so you could hook up a stereo pair of speakers and a Subwoofer (minimum 4 ohms) to it as per the Manual.

However, as you don't have a Sub, and want to connect 4 Speakers, I'd suggest you enable the High Pass Filter (HPF) for both pairs of speakers. The HPF ensures that everything but the deepest bass notes are directed to your full-range speakers. I don't think they can reproduce much Bass below 80 Hz, and they will struggle in the attempt. You could see if turning it off or on (before energizing the amp) makes an audible difference at the volume levels you typically listen at.

Without the Alpine Head unit model number, I cannot investigate if you can run your system adequately without the Sony Amp. If you want my guidance, please supply that detail.

I hope this is helpful.

Jim F****** rocks

 

[seachicken]

The Sony's Specifications are 70W x 4 / 1.0% THD when driving 4 Ohms from 20 to 20,000 Hz which is a good fit for your speakers. (I'm guessing the Memphis MXA60Ls are 4 ohms as their site doesn't provide that info.) It does have both a Low Pass and a High Pass filter so you could hook up a stereo pair of speakers and a Subwoofer (minimum 4 ohms) to it as per the Manual.

However, as you don't have a Sub, and want to connect 4 Speakers, I'd suggest you enable the High Pass Filter (HPF) for both pairs of speakers. The HPF ensures that everything but the deepest bass notes are directed to your full-range speakers. I don't think they can reproduce much Bass below 80 Hz, and they will struggle in the attempt. You could see if turning it off or on (before energizing the amp) makes an audible difference at the volume levels you typically listen at.

Without the Alpine Head unit model number, I cannot investigate if you can run your system adequately without the Sony Amp. If you want my guidance, please supply that detail.

I hope this is helpful.

Deck is a CDE-175BT, I appreciate your input Jim.

 

[-Jim-]

The Alpine specs for the amplifier section are (of course) a little less powerful that the Sony, but the effect is not going to be as much as you'd think.
Power Output: 18 Watts RMS x 4 at 4 Ohms <1%THD+N.

Generally the rule of thumb in Audio advises:

If you compare the maximum volume of a 50-watt amplifier with a 100-watt amplifier, the difference is only 3 dB, barely greater than the ability of the human ear to detect a difference. It would take an amplifier with 10 times more power (500 watts) to be perceived as being twice as loud—a 10 dB increase. (Of course the speakers have to be able to handle the increase in power.)

So in your case, you also need to factor in what power the speakers can handle before they start to distort, and get damaged. The MXA60L marine speakers are rated for 50 Watts RMS so you are limited by that as well. You are going to hear the difference at higher volume levels a bit, but it could be just fine where you want to listen to it.

Normally, I'm into home systems but I have mucked about with Car Stereos numerous times over the years. (When I was young in my first couple of cars I spent a lot of $$ and time on my car stereos.) Just for grins I plugged your data into an Sound Pressure Calculator that I use and I swagged you were ~6 feet away from the speakers. In that case maximum output from the Alpine alone would be 104 dB which is defined as beyond uncomfortably loud. Plugging in the 50 watt limit of the speakers (if driven by the Sony Amp) it's 108.8 dB which is almost as loud as a Jet Flyover and 300 meters.

According to OSHA, anything in excess of 1 hour listening to a 105 dB Sound Pressure Level (SPL) will begin to cause hearing damage. So it's always best to be cautious with loud sound.

Don't get me wrong, I like my tunes a Rockin' but there's a limit.

If I were you, I'd temporarily wire up just the Alpine to see if it's suitable for your needs. If so then you can remove the Sony Amp.

Good luck with whatever you decide. Please post back so we know what the conclusion is to your saga.

 

[seachicken]

The Alpine specs for the amplifier section are (of course) a little less powerful that the Sony, but the effect is not going to be as much as you'd think.
Power Output: 18 Watts RMS x 4 at 4 Ohms <1%THD+N.

Generally the rule of thumb in Audio advises:

If you compare the maximum volume of a 50-watt amplifier with a 100-watt amplifier, the difference is only 3 dB, barely greater than the ability of the human ear to detect a difference. It would take an amplifier with 10 times more power (500 watts) to be perceived as being twice as loud—a 10 dB increase. (Of course the speakers have to be able to handle the increase in power.)

So in your case, you also need to factor in what power the speakers can handle before they start to distort, and get damaged. The MXA60L marine speakers are rated for 50 Watts RMS so you are limited by that as well. You are going to hear the difference at higher volume levels a bit, but it could be just fine where you want to listen to it.

Normally, I'm into home systems but I have mucked about with Car Stereos numerous times over the years. (When I was young in my first couple of cars I spent a lot of $$ and time on my car stereos.) Just for grins I plugged your data into an Sound Pressure Calculator that I use and I swagged you were ~6 feet away from the speakers. In that case maximum output from the Alpine alone would be 104 dB which is defined as beyond uncomfortably loud. Plugging in the 50 watt limit of the speakers (if driven by the Sony Amp) it's 108.8 dB which is almost as loud as a Jet Flyover and 300 meters.

According to OSHA, anything in excess of 1 hour listening to a 105 dB Sound Pressure Level (SPL) will begin to cause hearing damage. So it's always best to be cautious with loud sound.

Don't get me wrong, I like my tunes a Rockin' but there's a limit.

If I were you, I'd temporarily wire up just the Alpine to see if it's suitable for your needs. If so then you can remove the Sony Amp.

Good luck with whatever you decide. Please post back so we know what the conclusion is to your saga.

Thanks for taking the time to explain this Jim, I don't know much about stereo systems which is why asked here in the first place and really appreciate your input. I kind of thought the amp was overkill for the deck and speakers and as @brutus mentioned power draw is a concern, certainly don't need a significant power draw like that drifting around fishing. I'll hook up the speakers to the deck as a test and let you know. Thanks again Jim.