Whats more important? changing Amplifier or Speakers?

[sunnydude]

Please don't say "both" because I know thats the correct answer

If I could only do one of the two, on my BMW M5 (5-series, F10 with just 'HiFi' (676) and not HarmanKardon or BangOlufsen or anything)

1. Change OE speakers to e.g. Focals that work with my OE amplifier

or

2. Changing my amplifier to a bimmer-tech audiotec fischer to get more out of the OE speakers

Relative cost of the two things aside, which would I be better off doing?

[spookly]

Obvious answer is that it depends on which is the weaker point in the system. On that car I have no idea.

If you do replace the speakers or amp alone then you'll need to make sure they match the impedance of the original kit, but I'm guessing you already knew that.

[defblade]

Use some test tones to find out where the OE HU/amp starts to clip. Don't turn it up past there, ever. If that's already loud enough for you, change the speakers. If not, change the amp. The OE speakers will probably work quite well with more power than they're really rated for, if they get an unclipped signal.

But, really, both.

[sunnydude]

defblade said:

Use some test tones to find out where the OE HU/amp starts to clip. Don't turn it up past there, ever. If that's already loud enough for you, change the speakers. If not, change the amp. The OE speakers will probably work quite well with more power than they're really rated for, if they get an unclipped signal.

But, really, both.

When you say clipping, is that where it starts distorting because of high volume? So for example, some songs on my OE head unit have fairly strong bass, and then as it gets louder, the bass feels like its getting quieter as well as distorted (like its just vibrating freely) ???

[defblade]

sunnydude said:

When you say clipping, is that where it starts distorting because of high volume? So for example, some songs on my OE head unit have fairly strong bass, and then as it gets louder, the bass feels like its getting quieter as well as distorted (like its just vibrating freely) ???

If you look at sound as a graph, it's a smooth wave. The shorter the distance between the peaks, the higher the note. The taller the waves, the louder the sound. When you turn the volume up, the waves stay the same length, but get taller. There's a point where the amplifier runs out of "taller" and instead of a nice smooth curve, you get a flat line across the top (and bottom peak) of each wave - the note has had the top clipped off. This kills speakers quicker than anything. Sadly, most volume knobs allow you to turn the amp up well past the point it starts clipping (I was very pleased to find my current Kenwood HU doesn't!). The speaker cone's movement follows that curve... when it is a curve, it moves forwards quickly up the slope (giving you the volume), slows as it reaches the top, then starts to gently then more quickly accelerate back the other way, then slowing again towards the bottom of the next bit of wave. When the signal is clipped, the cone is stopped as hard as it can be by the magnets on or near the steepest part of the slope and held there, then asked to instantly start moving backwards again at full speed once off the clipped portion and on the down slope.

This becomes an even bigger problem when you fit "nicer" speakers as they are generally actually more sensitive (which is why you fitted them) and far less rugged than OE ones and die even faster than the OE ones did as you're in such a rush to hear/show off how good your new speakers are, whacking the volume straight up and feeding your delicate, sensitive, not even run in, speakers a badly clipped signal leaving them bang backwards and forwards as hard as they can.

Your problem with the bass is hard to diagnose at a distance but possible reasons:
Poor mounting of the speakers - the front of the cone needs to be sealed from the back and most OE door mounts don't do this very well
The bass pressure from the speakers is starting to move other parts of the door, losing energy from your ears (Dynamat time)
Bass signal getting clipped (especially if bass boost is on - be aware of this when using test tones - if you're playing the amp at a just below the level that clipping starts, but you boost part of the range, that part will be clipping)
OE speakers knackered.

[sunnydude]

defblade said:

If you look at sound as a graph, it's a smooth wave. The shorter the distance between the peaks, the higher the note. The taller the waves, the louder the sound. When you turn the volume up, the waves stay the same length, but get taller. There's a point where the amplifier runs out of "taller" and instead of a nice smooth curve, you get a flat line across the top (and bottom peak) of each wave - the note has had the top clipped off. This kills speakers quicker than anything. Sadly, most volume knobs allow you to turn the amp up well past the point it starts clipping (I was very pleased to find my current Kenwood HU doesn't!). The speaker cone's movement follows that curve... when it is a curve, it moves forwards quickly up the slope (giving you the volume), slows as it reaches the top, then starts to gently then more quickly accelerate back the other way, then slowing again towards the bottom of the next bit of wave. When the signal is clipped, the cone is stopped as hard as it can be by the magnets on or near the steepest part of the slope and held there, then asked to instantly start moving backwards again at full speed once off the clipped portion and on the down slope.

This becomes an even bigger problem when you fit "nicer" speakers as they are generally actually more sensitive (which is why you fitted them) and far less rugged than OE ones and die even faster than the OE ones did as you're in such a rush to hear/show off how good your new speakers are, whacking the volume straight up and feeding your delicate, sensitive, not even run in, speakers a badly clipped signal leaving them bang backwards and forwards as hard as they can.

Your problem with the bass is hard to diagnose at a distance but possible reasons:
Poor mounting of the speakers - the front of the cone needs to be sealed from the back and most OE door mounts don't do this very well
The bass pressure from the speakers is starting to move other parts of the door, losing energy from your ears (Dynamat time)
Bass signal getting clipped (especially if bass boost is on - be aware of this when using test tones - if you're playing the amp at a just below the level that clipping starts, but you boost part of the range, that part will be clipping)
OE speakers knackered.

In that case my mids and tweeters are not clipping, but I suspect my subs are.
I'm not getting distortion off the mids and tweeters, even at 100% volume, but the subs feel over stretched.

I think i've answered my own question then - leave the amp alone, and change the subs?

[DennisCooper]

Hi,

For the current range of BMW's then an excellent way to increase the sound quality from all the oem modules etc is to change the speakers. There's custom fit, direct drop in higher quality and efficiency speaker kits from a number of reputable car audio speaker brands. Look to Focal, MTX, MB Quart, Gladen etc.

A relatively quick changeover and you'll get much better sound as they make the 'best' of the rest of the oem audio modules. To get better performance as your pocket allows, you can add a quality aftermarket amplifier to drive them with more power and efficiency and they'll sound even better.

Have a look at this link;

http://www.audiofile-incar.co.uk/index.php?option=...

Give them a call, or any other reputable and experienced car audio dealer who should advise pretty much the same.

It's only once you wish to get into even higher levels of high quality audio performance will you need to begin to add processors and amplifiers etc, so really does depend on how well you like your music reproduced!

Cheers, Dennis!

[sunnydude]

thanks Dennis, I'll have a look

[OldGermanHeaps]

I have always foundamping standard speakers to bemore effective than under driving aftermarket speakers.

[sunnydude]

OldGermanHeaps said:

I have always foundamping standard speakers to bemore effective than under driving aftermarket speakers.

There is mention of that sort of thing here actually: http://www.bimmer-tech.net/audio-amplifier-for-bmw...

Bimmer Tech Product Information said:

Are you interested in upgrading your BMW audio system but not sure how to do it? Ideally, we recommend you upgrade the amplifier and speakers at the same time. But if you have a limited budget, a Premium Audio System will do more for you than a speaker upgrade

After import taxes etc. its out of the question, it seems extremely expensive

Edited by sunnydude on Sunday 19th June 13:39