15 replies to this topic

[Z2TT]

Hi,

Just wondering which is a better amp in Terms of sound quality, I know the MRP-450 is a Class D Amp but don't know what Class the MRV-F407 is. If anyone knows i'd like to know.

Thanks.

[Tiger]

MRV-F407 would be my pick, but this is personal opinion. I'm very fond of those model amplifiers (old school V12 MRV-***) But if you can get access to the both of them.. demo them both and see which one get your ears singing.

[Winno]

I've had two F407s now. In fact, I sought out one when moving back home to Oz and stuck it in the family car for splits and sub duties.
I can't really comment on the newer amps but I am yet to be convinced that Class D amplification at this level is as good for sound quality. That's a general statement though. The Class D thing is primarily aimed at efficiency.

The F407 amps just go and go and do have a real look of quality about them. They were significantly better than the previous F405 that they replaced. They were made well and sounded pretty good even by today's standards. Lots of features, decent power and the manual is easily found on the web.
You could probably pick one up very cheap too. If you're buying, whip the bottom off and check things inside - look for water damage, repairs, etc - the usual.

Nice amp in a nut shell and was the basis for the F409 which was aimed at those who wanted an Alpine amp to compliment their Alpine F1 front end systems.

Edited by Winno, 24 November 2009 - 07:14 AM.

[shiny_car]

there is/was an MRP-F450 and an MRP-M450. the F450 is a 4-channel amp, class AB. the M450 is a monoblock, class D. so you need to clarify which amp is in question - i'm presuming the F450.

as above, the V12 amplifiers like the MRV-F407 are designed and built to a higher standard. the idea is that they feature bigger internal power supplies and more stiffening capacitors; this makes for much greater 'headroom' (reserve power), which ultimately means a general improvement in power output, and lower distortion, and better ability to cope with peaks. the F407 is class AB btw. whilst i don't have a great understanding of electronics, there's far more to it than that from what i can gather.

first pic is of a MRP-F450. second is the MRV-F407. if you have these amps yourself, you can open them up to have a look, just for fun.

[Tiger]

I should put the pics up of my MRV-1507 guts to further prove the point of the old school V12s

[Z2TT]

Do you have any documents that verify that the MRP-F450 is a Class A/B, because I had a look at this page :

http://www.alpine.co...asp?modelID=250

and under the specs it says it uses PWM, and as far as I know only Class D amplifiers
use PWM (Pulse Width Modulation)

[shiny_car]

interesting - i don't have the answer. my understanding has been that all of alpine's multichannel amplifiers (ie: not their monoblocks) have been class AB, with the exception of their PDX series and some of their 5-channel models. so i expect the F450 to be class AB.

they have typically made a point of their class D amps being 'class D'; that is, stating it amongst the features/specs of those amps that are class D.

my understanding of electronics is too limited. except i think the PWM in these multichannel amps, like the F450, relates only to the power supply function, and not to do with the actual audio signal output stage. i'll see if i can confirm.

[~Spyne~]

from the little reading i've done, i believe you're right shiny - a/b amps are often pwm, but only on the power supply section

[Z2TT]

If somebody is able to confirm with me if they are definitely both A/B Amps that would be good
It's hard to find any specs from a reliable website, and the users manuals for these amps don't even say. Is there anyway to identify if an amp is a Class D or A/B.

Thanks.

[shiny_car]

ring Alpine Australia, that would be the quickest/best way: 03 8787 1200

the 'desk' will probably put you through to the service/tech department. let us know what they say.

[simplesq]

shiny_car, on Nov 26 2009, 11:08 AM, said:

ring Alpine Australia, that would be the quickest/best way: 03 8787 1200

the 'desk' will probably put you through to the service/tech department. let us know what they say.

Just as an add on I'm yet to find a digital amp regardless of price that will outperform a really good class A/B. I'de go old school V12...

[Winno]

+1 on that one.
Can't beat a good old MOSFET class A/B V12 (or well designed bipolar if looking elsewhere)

[Luke352]

simplesq, on Nov 26 2009, 10:59 AM, said:

Just as an add on I'm yet to find a digital amp regardless of price that will outperform a really good class A/B. I'de go old school V12...

That's because there is no such thing as a "Digital" car audio amp on the market currently.

[Pulse-R]

MRV-F450 is a 5-channel amp, all classAB, the 5th channel is really 2-channels bridged. 4x50+200 RMS
MRV-F407 is a 4-channel amp, all classAB, and has a better power supply, but is rated lower. 4x40 RMS

[shiny_car]

Pulse-R, on Dec 1 2009, 08:28 PM, said:

MRV-F450 is a 5-channel amp

Sime, i believe we are talking about the MRP-F450 V-power amp (4-channel). not the MRV V12.