Quality of Amps

[indiglosolara]

After reading this post, In translation:

Use a class a/b amp for something like running your mids or componenets,
use a class d which is most Mono/1channel amps to run your subs.

Class d give you more the the power you will want for subs and class a/b give you the clearity of the sound such as mids tweeters and most highs.

This is what i would do if you want to run a clean system.
and of course diff brand of amps produce better sound then other but in general information this is the power band you wanna base the amps on
class a/b better clearity class d for more power/push to subs(also less likely to over heat when pushing subs rather then using a class a/b amp will cause to overheat easier cuz you are using more power and its continuist unlike the class d)

Kenny

[kronos98]

sweet! thanks for your help guys!

[pro956]

After reading this post, In translation:

Use a class a/b amp for something like running your mids or componenets,
use a class d which is most Mono/1channel amps to run your subs.

Class d give you more the the power you will want for subs and class a/b give you the clearity of the sound such as mids tweeters and most highs.

This is what i would do if you want to run a clean system.
and of course diff brand of amps produce better sound then other but in general information this is the power band you wanna base the amps on
class a/b better clearity class d for more power/push to subs(also less likely to over heat when pushing subs rather then using a class a/b amp will cause to overheat easier cuz you are using more power and its continuist unlike the class d)

Kenny

a class a/b amp would provide better clarity for you subs as well
class d/bd or whatever twise is put on it is very efficient, but isn't necessary unless you might have power issues. most people don't have that high powered systems, so it's not necessary for them.

[Luc]

a class a/b amp would provide better clarity for you subs as well

When you are talking about the 20-200 Hz range, it's really hard to differentiate better clarity. It just seems to be wasting the true design of Class A/B, just to have the crossover low-passed at 200-Hz. Since subs usually have larger magnets, voice coils, spider, etc., compared to car speakers, more conversion of electrical to mechanical energy is needed to have the subs "keep up" with the beat. Ever notice why 15"s seem to lag a bit in the beat? They're great for volume, but not the best for music. Thus, Class D/BD doesn't dissipate the energy as heat as much as A/B, which keeps the subs happy.

[indiglosolara]

ahhh... this explains it alot better.....

hahaha...

For example

If i was running 2 12" crystal subs 600watts rms each im putting out about 1200watts rms. im running a JBL 600.1 mono class d amp. should i stay with this amp or get a 2 channel classa/b amp with more power..

I have been thinking about switching to a ppi amp but not the mono ampo but class a/b.

[Jackass-Jeff]

I have been thinking about switching to a ppi amp but not the mono ampo but class a/b.

Didn't you say that you didn't want a PPI because they overheat easily and also because Richard already has one?

[indiglosolara]

Yea, But that is the Mono class that i heard they over heat. im thinking of going with the a/b class cuz im going to get higher powered one. plus im not getting one of the new ones. the new ones dont have as good qaulity as the older models. richard has one of the older models and it sounds pretty good.

this is why i am rethinking it and getting one of the older ppi 2 chan a/b class amps.

[swimshady906]

wow Luc. nice

[HKSV6SLE]

how are the PPi amps anywys? im thinking bout redoing my system again soon....my fosgate amp tends to heat up quick...but then again...i think it needs to be rewired..or something....i wanna get the jbl crown amps....hehe not enuff bass.....

[indiglosolara]

Alot of the Older PPI amps are really good. I haven't heard much good things about the new ones(Guessing the moves to a cheaper location to produce these amps). For some reason they overheat while pushing your subs really hard. But i would go for one of the older models like richard has. His looks good and pushes pretty hard for his 3 subs. I would love to get one like his but its hard to find. Im in the serach for one at the moment.

Kenny

[Gunman]

I hope you will all understand that there is NO such thing as a digital amplifier, that's just marketing terms, since digital implies better. Those mono-amps are all rated Class D and D does NOT equal digital. It's just a design parameter, where it's at least 80% efficient with limited bandwidth. Thus, they are perfect for subs, since you wouldn't want to feed something like 1-kHz to a sub anyway. Class A is the least efficient, but the cleanest, since current runs through the transistors even when the amplifiers are NOT on. Class B is more efficient, but doesn't produce the best quality, thus, Class A/B comes along, with designs from both, but only operating about 50% efficiency. Class A, B, and A/B all have full bandwidth support, thus, using them to run subs may be a waste of productivity and power. Class D uses a switching power supply, thus, doesn't require constant power consumption. Getting into more specifics would be too much to list, so these are just in generality. After studying all the different classes, FET/BJT types, etc., it tends to escape memory, unless of course you are a professor.

Alpine is the first to use this, and trust me they beat into us the whole process on how the signal is converted over to digital. It explains how 20 and 30 amp current draws, result in over 500 watts. For the most part, they havent caught on industry wise. Trust me, everyone in that training room didnt believe the instructor, but afterwards, there where some advantages to it. Sound wise, it doesnt have the punch I would like to hear out of an alpine amp, but i can understand eventually things going that way. I guess we will have to wait and see.

[Gunman]

how are the PPi amps anywys? im thinking bout redoing my system again soon....my fosgate amp tends to heat up quick...but then again...i think it needs to be rewired..or something....i wanna get the jbl crown amps....hehe not enuff bass.....

the whole thing with rockfords........THEY GET HOT, thats part of the whole design, they get the heat off the board quickly to run more effecient. If you play a rockford long and hard enough, you can burn your hand to the touch.

[Luc]

Alpine is the first to use this, and trust me they beat into us the whole process on how the signal is converted over to digital. It explains how 20 and 30 amp current draws, result in over 500 watts. For the most part, they havent caught on industry wise. Trust me, everyone in that training room didnt believe the instructor, but afterwards, there where some advantages to it. Sound wise, it doesnt have the punch I would like to hear out of an alpine amp, but i can understand eventually things going that way. I guess we will have to wait and see.

A trusted mobile salesperson (former installer/Road Shop manager) also told me about Alpine's "digital" amp, he mentioned the MRD-M300 as one of them. I have no doubt that the signal can be converted to digital using an ADC. Within the digital bitstream of 1's and 0's, the signals can be manipulated for faster transfer of information. I just don't see how they can increase the gain using bits, to me, that's unfathomable. Eventually, the digital bits will need to have a DAC to convert it to usable signal, and thus, using analog devices to amplify it. Lastly, the output stage needs to have impedance matched for most power dissipation, and that requires analog devices also.

Digital components will always use less current, since they don't need to have the power protection compared to analog devices, like op amps. Instead of using capacitors in the millifarad (10^-3) range for the analog components, microfarad (10^-6) capacitors can be used for the digital components. That's 1000x less!

I was VERY tempted to open up that Alpine amp, so I can really see what's inside, but didn't get the green light. From reading the description on Alpine's website, it's just manipulation of the digital streams so you can adjust time delay, crossover setting, and whatever it controls. It's similar to the MX and T CORR functions on their headunits. I also read the owner's manual, and it basically replaces all those potentiometers and switches that you adjust for gain, crossover setting, filtering, etc. to a digital domain. Thus, it is NOT a digital amplifier, but digitally-adjustable settings; only FETs or BJTs can amplify signals.

This technology isn't new, that's what any DSPs do, but new to the car amplifier. Ultimately, it's all just marketing hype, nothing else.

[Gunman]

The first thing I asked him was to play a 40 htz test tone and grabbed my meter. I got a reading of 43.7 volts. Since we know that E=P X R squared rooted, I reversed the formula and came up with 477.4 watts. Out of an 20 amp current draw, that was impresive. Still dont like the amps, but if you get the chance to open one up let me know, Ive been hoping one came back so I could, but no luck as of yet. Again that might be awhile since its rare for any alpines to come back. Me, for the money I really like JL audio amps.

[Luc]

I'm going to keep trying to get that amp opened up. But I'm not surprised that the sound may not be good, since all the manipulation of the bitstream, there are variations that will cause the signal to deteriorate. Thus, my preference is still towards potentiometers & switches. Ditto on the JL.