Class D vs. class a/b Amplifiers

[Jleff8621 10+ year member]

I am trying to decide which one i should get. i would be hooking it up to two spr-50c speakers. Right now i have them hooked to the HU but its just not enough. Without an amp my two sub just over power them. When the subs hit i cant even hear them. So im fine on bass but i want nice loud highs and mids that i can hear when the subs hit. So which amp would be ideal for this? And whyy?

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[RicksI30 10+ year member]

Either one will work just fine.

 

[neo_styles 10+ year member]

^^^This. Class D is gentler on your electrical than A/B and normally comes in a smaller profile. For just powering your comps, either one will work fine.

 

[hispls 5,000+ posts]

If money isn't an issue buy a good full range class D, there is no downside. If you're thinking of buying a budget priced full range class D I suspect you'd regret it. The ones that are worth owning are not cheap.

 

[Tenacious]

They "say" that Class A/B have better SQ because there's always a current going through it and other crap like that... But there's really no proof to back it up. I think it's another one of those things like capacitors - pretty much useless.

Anyway back on subject, a class D will usually be at least 20% more efficient, but either class of amps will work well.

 

[Jleff8621 10+ year member]

So theres really no difference between the twoo? And id be getting the Alpine MRX-F65. Is that a good amp? I mean i dont think you can go wrong with alpine but i just want to make sureeee.

 

[Beatin' 10+ year member]

d class full range amps are known to have high distortion but how do the manufacturers reduce it, I don't know.......

 

[Jleff8621 10+ year member]

Sooo the a/b would sound betterr?

 

[neo_styles 10+ year member]

Ignore Beatin'. He tends to make remarks without proof to back it up. The Alpine you chose is fine.

 

[Tenacious]

d class full range amps are known to have high distortion but how do the manufacturers reduce it' date=' I don't know.......[/quote']
cheap class D amps*

This is mainly because class D have been 'traditionally' used as sub amps and anything below about 10% distortion isn't too noticeable

 

[Jleff8621 10+ year member]

So that alpine would sound good and loud?

 

[Rich B 5,000+ posts]

d class full range amps are known to have high distortion but how do the manufacturers reduce it' date=' I don't know.......[/quote']
They use whats called "a brick wall filter" that removes most of the switching noise above 20khz that class D makes.

In component amps you wont be saving much amperage draw versus using an A/B amp anyway, so if you are building for SQ use an A/B if its within your budget.

 

[keep_hope_alive Premium Member]

i think amps sound different because of slew rate, not just THD. a well made Class D will be just fine. Efficiency comes with how long the transistors are "on". traditional class A/B allows some overlap so half of the amp is still on when not being used - the result is much less distortion over Class B but lower power consumption (better efficiency) compared to Class A. As mentioned, modern Class D (and similar hybrids) switch much faster, have proper filtering, and are just fine. but many people prefer an amp topology that doesn't require filters to remove the nasty side-effects.

for speakers, power is low anyway and efficiency isn't much of a concern. class A/B is fairly cheap, especially used.

 

[cablguy184 10+ year member]

I have NO problems with my Class A/B amps ...

 

[zako 10+ year member]

So theres really no difference between the twoo? And id be getting the Alpine MRX-F65. Is that a good amp? I mean i dont think you can go wrong with alpine but i just want to make sureeee.

It should be good. MRX amps are some of the best budget amplifiers. I'd recommend either this or PPI Phantom P900.4. My only concern with Class A/B amplifiers is that if I drive my midbass speakers and play music loud, they can run stupid hot during Texan summers, so they're a bit more sensitive to where you place them. On the other hand, Class A/B amps have gotten much cheaper these days. Consider the PPI bk800.4. It's power output is close to P900.4, but it costs a bit less (and 1.5x as long in length..)