Speakers - Page 4

kourgath · 23rd December 2014, 12:37

Ok honestly can't really say but you are comparing a 150 quid amp with 100 quid one so all other things being equal I'd expect the one costing 50% more to sound better :-) you could look at Pioneer GM-D8604 or Kenwood KAC-8405 for the same dosh. I cannot see any more details on the vibe amp (their website is rubbish) but ask yourself are you paying extra for the name? Best bet would be to audition the amps using a known cd on the same speaker setup (even if not the hertz).
Sorry I can't give you a definite answer.

gritbox · 23rd December 2014, 12:53

vibe stats:

<LI style="PADDING-BOTTOM: 0px; PADDING-LEFT: 0px">Max Power: 1200 w<LI style="PADDING-BOTTOM: 0px; PADDING-LEFT: 0px">RMS Out @4ohm stereo: 4 x 100 w<LI style="PADDING-BOTTOM: 0px; PADDING-LEFT: 0px">RMS Out @2ohm stereo: 4 x 125 w<LI style="PADDING-BOTTOM: 0px; PADDING-LEFT: 0px">RMS Out @4ohm bridged: 2 x 300 w<LI style="PADDING-BOTTOM: 0px; PADDING-LEFT: 0px">Signal To Noise Ratio: 88 dB<LI style="PADDING-BOTTOM: 0px; PADDING-LEFT: 0px">Frequency Response: 20 - 20,000 Hz<LI style="PADDING-BOTTOM: 0px; PADDING-LEFT: 0px">Crosover Type: LP/HP/Flat<LI style="PADDING-BOTTOM: 0px; PADDING-LEFT: 0px">Crossover Range: 30 - 1,000 Hz<LI style="PADDING-BOTTOM: 0px; PADDING-LEFT: 0px">Crpossover Slope: 24dB<LI style="PADDING-BOTTOM: 0px; PADDING-LEFT: 0px">Bass Enhance<LI style="PADDING-BOTTOM: 0px; PADDING-LEFT: 0px">Height: 54 mm<LI style="PADDING-BOTTOM: 0px; PADDING-LEFT: 0px">Width: 329 mm<LI style="PADDING-BOTTOM: 0px; PADDING-LEFT: 0px">Depth: 165 mmfrom looking at that, the freq response anyway is worse than the pioneer?

trimani · 23rd December 2014, 22:02

Quote:

Originally Posted by gritbox

vibe stats:

<LI style="PADDING-BOTTOM: 0px; PADDING-LEFT: 0px">Max Power: 1200 w<LI style="PADDING-BOTTOM: 0px; PADDING-LEFT: 0px">RMS Out @4ohm stereo: 4 x 100 w<LI style="PADDING-BOTTOM: 0px; PADDING-LEFT: 0px">RMS Out @2ohm stereo: 4 x 125 w<LI style="PADDING-BOTTOM: 0px; PADDING-LEFT: 0px">RMS Out @4ohm bridged: 2 x 300 w<LI style="PADDING-BOTTOM: 0px; PADDING-LEFT: 0px">Signal To Noise Ratio: 88 dB<LI style="PADDING-BOTTOM: 0px; PADDING-LEFT: 0px">Frequency Response: 20 - 20,000 Hz<LI style="PADDING-BOTTOM: 0px; PADDING-LEFT: 0px">Crosover Type: LP/HP/Flat<LI style="PADDING-BOTTOM: 0px; PADDING-LEFT: 0px">Crossover Range: 30 - 1,000 Hz<LI style="PADDING-BOTTOM: 0px; PADDING-LEFT: 0px">Crpossover Slope: 24dB<LI style="PADDING-BOTTOM: 0px; PADDING-LEFT: 0px">Bass Enhance<LI style="PADDING-BOTTOM: 0px; PADDING-LEFT: 0px">Height: 54 mm<LI style="PADDING-BOTTOM: 0px; PADDING-LEFT: 0px">Width: 329 mm<LI style="PADDING-BOTTOM: 0px; PADDING-LEFT: 0px">Depth: 165 mmfrom looking at that, the freq response anyway is worse than the pioneer?

Is this an accurate description ?
Any discrepancy in this type of information makes it impossible to analise.
One dot, one =, one missing space makes it inaccurate, and unusable.
For example, does the original write up spell 'crossover' three different ways ?
trimani

gritbox · 24th December 2014, 09:27

dont know why it came out like that, apologies!

vibe stats are:

Max Power: 1200w RMS Out @4ohm stereo: 4 x 100 w RMS Out @2ohm stereo: 4 x 125 w<RMS Out @4ohm bridged: 2 x 300 w<Signal To Noise Ratio: 88 dB<Frequency Response: 20 - 20,000 Hz<Crosover Type: LP/HP/Flat<Crossover Range: 30 - 1,000 Hz<Crpossover Slope: 24dBBass Enhance

yep, they really do spell it 3 different ways...direct copy an paste!

the vibe is 20 to 20khz, which is a lesser spectrum than the alpine, so right away does the alpine win?

kourgath · 24th December 2014, 10:24

Hiya, both amp specs could be misleading as neither say the 3dB points at power and it is a common way of not telling the full picture so you have a 10-50khz band at 1w but at higher levels the freq response get messy.
It is unusual for a company to give the full proper specs as most customers just look at the power figures and bigger is better...
Another aspect is the power requirements of the amp. So the vibe asks for 15amp max but the kenwood linked wants 34 amp, is your wiring up to the job? The vibe being class D is more efficient than the kenwood or the alpine as they are class AB which is less efficient. Class D can be upto 90% efficient but due to the way they work the last stage which is the reconstruction filter is extremely important.
There may be a reason for video to use 3 spellings as many people may not know the correct spelling and so search terms in Google for example would pick up the difference.
Our hearing is limited to around 20-22kHz so anything above this isn't as important as your speakers probably can't produce this anyway. Also with a class D you want a very high pwm so as not to introduce extra noise into your signal.
It is hard to give a definite answer but go with the one you want. Either will b,e a significant improvement on the standard amp in your head unit.

gritbox · 24th December 2014, 10:33

good man thansk

Also with a class D you want a very high pwm so as not to introduce extra noise into your signal.

whats pwm!?

kourgath · 24th December 2014, 10:47

Just a short search and found this http://www.hometheatershack.com/foru...left-right.jpg where this guy has measured the freq response in his car. You get an idea that what ideally should be a flat plot it gets quite messy once in the car.

kourgath · 24th December 2014, 10:51

Also http://www.restivo.org/blog/archives...ency-responses

kourgath · 24th December 2014, 11:14

Alpine get a good view with most reviews saying that alpine is about clarity not show power.

http://www.talkaudio.co.uk/index.php...mplifier-r1096

Looking at top rated amps on various sellers pages you get alpine, pioneer, jl, kenwood but not vibe. Eg http://www.bestcovery.com/best-car-amplifier-overall
Or
http://www.testfreaks.co.uk/car-amplifiers/

kourgath · 24th December 2014, 11:35

PWM is pulse width modulation and is how a class D amp works and why it has a very good efficiency rating. Simply put this pwm freq needs to be much higher than we can hear otherwise we hear the artifacts it introduces into the sound. So above 320khz but then you also need a good reconstruction filter to turn the pwm'd output back to normal sound. Also think that this freq is close to the oversampling that some cd players do so could have consequences. This reconstruction filter is hard to design well and needs very good components to work well. http://www.soundonsound.com/sos/jun0...udandlight.htm or http://www.bcae1.com/ampclass.htm
Basically a well designed class D is as good as a well designed class ab but there does need to be good design and components.
It's a minefield and this is where marketing gets in and tries to simplify it but also tries to make what they are selling seem better than others.
Cheers Gavin

24th December 2014, 11:35	#40
kourgath Avid contributor Rover 75 Saloon Join Date: Mar 2014 Location: On the Border between Cornwall and Devon, near Tavistock Posts: 153 Thanks: 68 Thanked 22 Times in 21 Posts	PWM is pulse width modulation and is how a class D amp works and why it has a very good efficiency rating. Simply put this pwm freq needs to be much higher than we can hear otherwise we hear the artifacts it introduces into the sound. So above 320khz but then you also need a good reconstruction filter to turn the pwm'd output back to normal sound. Also think that this freq is close to the oversampling that some cd players do so could have consequences. This reconstruction filter is hard to design well and needs very good components to work well. http://www.soundonsound.com/sos/jun0...udandlight.htm or http://www.bcae1.com/ampclass.htm Basically a well designed class D is as good as a well designed class ab but there does need to be good design and components. It's a minefield and this is where marketing gets in and tries to simplify it but also tries to make what they are selling seem better than others. Cheers Gavin Last edited by kourgath; 24th December 2014 at 11:37..

23rd December 2014, 12:37	#31
kourgath Avid contributor Rover 75 Saloon Join Date: Mar 2014 Location: On the Border between Cornwall and Devon, near Tavistock Posts: 153 Thanks: 68 Thanked 22 Times in 21 Posts	Ok honestly can't really say but you are comparing a 150 quid amp with 100 quid one so all other things being equal I'd expect the one costing 50% more to sound better :-) you could look at Pioneer GM-D8604 or Kenwood KAC-8405 for the same dosh. I cannot see any more details on the vibe amp (their website is rubbish) but ask yourself are you paying extra for the name? Best bet would be to audition the amps using a known cd on the same speaker setup (even if not the hertz). Sorry I can't give you a definite answer.

23rd December 2014, 12:53	#32
gritbox Loves to post MG ZT 190 Join Date: Aug 2014 Location: Glasgow Posts: 497 Thanks: 25 Thanked 36 Times in 24 Posts	vibe stats: <LI style="PADDING-BOTTOM: 0px; PADDING-LEFT: 0px">Max Power: 1200 w<LI style="PADDING-BOTTOM: 0px; PADDING-LEFT: 0px">RMS Out @4ohm stereo: 4 x 100 w<LI style="PADDING-BOTTOM: 0px; PADDING-LEFT: 0px">RMS Out @2ohm stereo: 4 x 125 w<LI style="PADDING-BOTTOM: 0px; PADDING-LEFT: 0px">RMS Out @4ohm bridged: 2 x 300 w<LI style="PADDING-BOTTOM: 0px; PADDING-LEFT: 0px">Signal To Noise Ratio: 88 dB<LI style="PADDING-BOTTOM: 0px; PADDING-LEFT: 0px">Frequency Response: 20 - 20,000 Hz<LI style="PADDING-BOTTOM: 0px; PADDING-LEFT: 0px">Crosover Type: LP/HP/Flat<LI style="PADDING-BOTTOM: 0px; PADDING-LEFT: 0px">Crossover Range: 30 - 1,000 Hz<LI style="PADDING-BOTTOM: 0px; PADDING-LEFT: 0px">Crpossover Slope: 24dB<LI style="PADDING-BOTTOM: 0px; PADDING-LEFT: 0px">Bass Enhance<LI style="PADDING-BOTTOM: 0px; PADDING-LEFT: 0px">Height: 54 mm<LI style="PADDING-BOTTOM: 0px; PADDING-LEFT: 0px">Width: 329 mm<LI style="PADDING-BOTTOM: 0px; PADDING-LEFT: 0px">Depth: 165 mmfrom looking at that, the freq response anyway is worse than the pioneer?

24th December 2014, 09:27	#34
gritbox Loves to post MG ZT 190 Join Date: Aug 2014 Location: Glasgow Posts: 497 Thanks: 25 Thanked 36 Times in 24 Posts	dont know why it came out like that, apologies! vibe stats are: Max Power: 1200w RMS Out @4ohm stereo: 4 x 100 w RMS Out @2ohm stereo: 4 x 125 w<RMS Out @4ohm bridged: 2 x 300 w<Signal To Noise Ratio: 88 dB<Frequency Response: 20 - 20,000 Hz<Crosover Type: LP/HP/Flat<Crossover Range: 30 - 1,000 Hz<Crpossover Slope: 24dBBass Enhance yep, they really do spell it 3 different ways...direct copy an paste! the vibe is 20 to 20khz, which is a lesser spectrum than the alpine, so right away does the alpine win?

24th December 2014, 10:24	#35
kourgath Avid contributor Rover 75 Saloon Join Date: Mar 2014 Location: On the Border between Cornwall and Devon, near Tavistock Posts: 153 Thanks: 68 Thanked 22 Times in 21 Posts	Hiya, both amp specs could be misleading as neither say the 3dB points at power and it is a common way of not telling the full picture so you have a 10-50khz band at 1w but at higher levels the freq response get messy. It is unusual for a company to give the full proper specs as most customers just look at the power figures and bigger is better... Another aspect is the power requirements of the amp. So the vibe asks for 15amp max but the kenwood linked wants 34 amp, is your wiring up to the job? The vibe being class D is more efficient than the kenwood or the alpine as they are class AB which is less efficient. Class D can be upto 90% efficient but due to the way they work the last stage which is the reconstruction filter is extremely important. There may be a reason for video to use 3 spellings as many people may not know the correct spelling and so search terms in Google for example would pick up the difference. Our hearing is limited to around 20-22kHz so anything above this isn't as important as your speakers probably can't produce this anyway. Also with a class D you want a very high pwm so as not to introduce extra noise into your signal. It is hard to give a definite answer but go with the one you want. Either will b,e a significant improvement on the standard amp in your head unit.

24th December 2014, 10:33	#36
gritbox Loves to post MG ZT 190 Join Date: Aug 2014 Location: Glasgow Posts: 497 Thanks: 25 Thanked 36 Times in 24 Posts	good man thansk Also with a class D you want a very high pwm so as not to introduce extra noise into your signal. whats pwm!?

24th December 2014, 10:47	#37
kourgath Avid contributor Rover 75 Saloon Join Date: Mar 2014 Location: On the Border between Cornwall and Devon, near Tavistock Posts: 153 Thanks: 68 Thanked 22 Times in 21 Posts	Just a short search and found this http://www.hometheatershack.com/foru...left-right.jpg where this guy has measured the freq response in his car. You get an idea that what ideally should be a flat plot it gets quite messy once in the car.

24th December 2014, 10:51	#38
kourgath Avid contributor Rover 75 Saloon Join Date: Mar 2014 Location: On the Border between Cornwall and Devon, near Tavistock Posts: 153 Thanks: 68 Thanked 22 Times in 21 Posts	Also http://www.restivo.org/blog/archives...ency-responses

24th December 2014, 11:14	#39
kourgath Avid contributor Rover 75 Saloon Join Date: Mar 2014 Location: On the Border between Cornwall and Devon, near Tavistock Posts: 153 Thanks: 68 Thanked 22 Times in 21 Posts	Alpine get a good view with most reviews saying that alpine is about clarity not show power. http://www.talkaudio.co.uk/index.php...mplifier-r1096 Looking at top rated amps on various sellers pages you get alpine, pioneer, jl, kenwood but not vibe. Eg http://www.bestcovery.com/best-car-amplifier-overall Or http://www.testfreaks.co.uk/car-amplifiers/