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SpankingVanillaice
02-10-2008, 11:04 AM
What is the difference between Class A/B amps and Class D type? Are they the same but only difference is that Class D is smaller for small monitors like the M-Audio AV-20? I know that M-Audio says that all monitors use the same technology so I would assume all of them are durable and give long life even for small monitors like the AV-20. I just wanted to make sure that the AV-20 will last a very long time without problems even after 5 years if I take good care of them.


I don't really need to know how they are made but basicaly I need to know which amp gives better life meaning which will last longer and which is built better. Or are they both build durable and give the same amount of life? I just want to make sure that all monitors that M-Audio makes will last a long time if you take good care of them. Expecialy I need to make sure that the AV-20 monitors will last as long as the higher end ones like the BX5a.

JohnMichael
02-10-2008, 11:36 AM
SVI both A/B and D amps can be made to be durable and long lasting. I own a Cambridge Audio int. amp that operates in Class A/B and an Onkyo int. amp that operates in Class D. Both are well made good sounding amps. Class D is more efficient if you are going green. Personally I prefer the sound of the Onkyo. I do know there are smaller less expensive Class D amps but I am not familiar with them.

Do you have any brand and model of amps that you are considering?

basite
02-10-2008, 12:05 PM
Class A/B amps are less efficient, as John already pointed out.

I believe Class D amps are switching amps, which saves energy, so they're better if you're going green. when done bad, they can have horrible disortions though.
in the really high price classes, class A/B is still better than class D IMO, not that class D is bad, but in the exotic gear, the A/B amps sound better IMO. Class A still rules them all, but is really inefficient though.

Both can be of the same build quality, there are bad built class A/B amps, and there are good built class D amps, and vice versa. both last equally long.

since class D amps are more efficient, thus they put out less heat, and can be smaller considering the power they output. however, yet again, for your 'monitors', the size difference will be marginal, since the amps don't put out that much power, so can be pretty small anyway.

Keep them spinning,
Bert.

SpankingVanillaice
02-10-2008, 02:12 PM
Well I can say that the AV-40 monitors use A/B type amp so does that mean that the AV-40 sounds better? Or in this case they will sound the same since they are about the same price range? Only the AV-20 uses the D type and probley since they are very compac and small. But does class D amps makes alot of distortion compaired to A/B type that the AV-40 uses. Btw what do you guys mean when you said if you are going green on the D type amp?

SpankingVanillaice
02-10-2008, 02:17 PM
I' am not getting the AV-40 monitors since I already decided to get the AV-20 monitors but I just wanted to know why the AV-20 uses Class D instead of Class A/B. I can only think the reason why is that since as you guys said they can make small amps using Class D.

basite
02-10-2008, 02:22 PM
Well I can say that the AV-40 monitors use A/B type amp so does that mean that the AV-40 sounds better? Or in this case they will sound the same since they are about the same price range? Only the AV-20 uses the D type and probley since they are very compac and small. But does class D amps makes alot of distortion compaired to A/B type that the AV-40 uses. Btw what do you guys mean when you said if you are going green on the D type amp?


no. it does not nessicarily mean the AV-40 will sound better (well, in this case it would, but that's probably not because of the amp).
when I say 'exotic audio products', I mean stuff like bryston, Mcintosh, Krell, Accuphase, Belcanto, Gryphon, Tact.
then, a A/B might sound better. of course there are class D amps that sound better as class A/B amps too, it's just that at the moment, one can yield better results with a class A/B design, and definately with a class A design.

'going green' means 'saving' or 'protecting' the environment. saving power. The class D amps consume less power compared to what they output than A/B amps.

keep them spinning,
Bert.

Mr Peabody
02-10-2008, 07:32 PM
Class D uses a digital switching power supply, so they do not have the heat or weight of a class A/B. Many subwoofer manufacturers have gone to digital, or Class D, amps because they can get huge amounts of power and still fit the amp inside the cabinet and keep it a reasonable size. There are many companies who have now over come the problems with digital amps, namely the distortion factor. T+A comes to mind, excellent sounding gear. To give you an idea, my LINN amp is actually class V but it's similar to D or T, it weighs 11 lbs and can deliver 5x125 wpc. I believe that is really conservative because it can rock 5 Dynaudio speakers as loud as I care to listen without a ripple. You can see how this type of amp could be valuable in an amplified speaker. I can't remember exactly how efficient Class D is but it's very high meaning it uses most of the power it draws, less waste, that's what's meant by "going green". Going green is very politically correct these days.

Class A/B is your typical design you see most. From what I've seen the class A/B is still the choice for brute force and driving a difficult load. It is much less efficient and much of the energy wasted is dissipated as heat.

Feanor
02-11-2008, 03:39 AM
Class D uses a digital switching power supply, so they do not have the heat or weight of a class A/B. ...

Some Class D or "digital" amps don't have switching power supplies and some Class A/B amps do, the latter are sometimes referred to as Class H (I think: ?? ).

My former Bel Canto eVo amp was Class "T" for Tripath, a proprietary variation of Class D; it had a standard "linear" power supply, not a switching supply.

SpankingVanillaice
02-11-2008, 08:59 AM
So does that mean that the AV-20 monitors don't save energy since it doesn't have that switch?

basite
02-11-2008, 09:03 AM
So does that mean that the AV-20 monitors don't save energy since it doesn't have that switch?


switch?

we're not talking about an on off switch here eh spanky...

we're talking about the power supply, something in the amp.

topspeed
02-11-2008, 11:57 AM
Spanky,

I'll make this easy for you: Don't worry about it. Buy whichever sounds better to you.

The Class A/B will use more energy, but you don't foot the bill anyway. If you really want to understand the difference between amplifier topologies, check out wikipedia. The most important part to understand is that amps sound different, regardless of topology. Not all A/B's sound the same, not all D's sound the same. Lot's of variables that you simply shouldn't worry about.

You are really over-thinking this big guy.

SpankingVanillaice
02-11-2008, 05:17 PM
I just got my AV-20 today and they sound soo amazing for there size. Very clear and clean highs and good lows and mids. They are really a miniture studio monitor. The only problem I have is that they don't go as loud as I want them to go but of cource they aren't going to be very loud since they are very small monitors. I do know that the monitors have a output current limiting so you can't blow the drivers so maybe that's why they don't go too loud.

Mr Peabody
02-11-2008, 07:29 PM
Geez Feanor get technical :) I did get my switching confused, power supplies with output devices. I'm sure some class D have both.

Here if anyone cares: http://en.wikipedia.org/wiki/Electronic_amplifier#Power_amplifier_classes

SpankingVanillaice
02-12-2008, 07:32 AM
Well overall does this mean that if I had the AV-40 monitors it will use soo much electricity and alot of heat will be there and also will my electric bill go few dollars higher since it has Class A/B amp compaired to the AV-20 that is Class D amp?

basite
02-12-2008, 07:49 AM
Well overall does this mean that if I had the AV-40 monitors it will use soo much electricity and alot of heat will be there and also will my electric bill go few dollars higher since it has Class A/B amp compaired to the AV-20 that is Class D amp?


um?

maybe you haven't noticed, but your clockradio will consume about the same as your speakers.

you will notice a price increase in your electric bill, if, and only if, you have 'high power' amps. The small thingies in your 'speakers' aren't going to consume that much. If they consume 30 watts at peaks, it'd be much.

Keep them spinning,
Bert.

SpankingVanillaice
02-12-2008, 08:50 AM
So you are saying that something this small like the AV-20 or the AV-40 won't make a difference at all on how much power it uses?

basite
02-12-2008, 08:52 AM
So you are saying that something this small like the AV-20 or the AV-40 won't make a difference at all on how much power it uses?


it won't make a noticable difference on your electric bill. No lights will dim, you won't melt your powerlines. No.

leaving your pc on for an hour will probably consume more power than those 'speakers' consume in a whole day, if you use the speakers at full power all the time, otherwise it would probably take a couple of days...

johnny p
02-12-2008, 04:39 PM
Back to square one...... everything is cyclical!

Rich-n-Texas
02-12-2008, 05:29 PM
I made my final choice and I got my BX5a back since they were the most expensive monitors out of all of them...
Earlier you were concerned about how much power your tiny little computer speakers consumed. :crazy: :crazy: :crazy:

I think you should upgrade to a more expensive computer. Make them speakers really sing!

GMichael
02-13-2008, 06:58 AM
Earlier you were concerned about how much power your tiny little computer speakers consumed. :crazy: :crazy: :crazy:

I think you should upgrade to a more expensive computer. Make them speakers really sing!

Maybe just an updated sound card.

Florian
02-13-2008, 07:06 AM
As long as the amps inside your speakers are not as big as the ones in my speaker, then dont worry about it :-)

SlumpBuster
02-14-2008, 12:34 PM
They are really a miniture studio monitor

Umm, no they are not studio monitors. They are computer speakers. I've been in plenty of recording studios and never saw anything like those, unless they were hooked up to a computer.



maybe that's why they don't go too loud.

Umm, no. They don't play loud because they are .... computer speakers.

You'll like these: http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=309-160

Oh, and if you are going to post pictures of your computer set up, would you please at least hide your "hand" lotion. I can't fathom the horrors that have occured in front of that monitor.

Luvin Da Blues
02-14-2008, 01:12 PM
Oh, and if you are going to post pictures of your computer set up, would you please at least hide your "hand" lotion. I can't fathom the horrors that have occured in front of that monitor.

ROFLMAO...Glad I didn't open the pics.

audio amateur
02-14-2008, 02:47 PM
You'll like these: http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=309-160

Those look incredibly nasty

SpankingVanillaice
02-14-2008, 03:57 PM
I special ordered the Edirol MA-7A monitors and they said they should get them around next week hopefuly. I gave the BX5a as a trade since I don't really need pro studio moinitors since I don't mix or anything like that. But the Edirol MA-7A seems to be cool since it has the bass enhancer.




MA-7A: Stereo Micro Monitors
Features
The MA-7A Stereo Reference Speakers are the ideal solution for musicians and computer users who demand the best audio quality possible in a very confined space. The MA-7As are extraordinarily small reference speakers, but are capable of producing incredible sound. These speakers are perfect for desktop use, where space is of the utmost consideration.


Here are some specs for these monitors.


Bass Enhancer
Front-accessible Volume & Tone controls
Subwoofer output port for bass boost
7W-per-channel desktop monitor (pair)
76mm (3") full-range speaker, bass-reflex enclosure
2 independent source inputs; 1/8" line and RCA pin line (L/R)
1/8" headphone port
Magnetically shielded
More Info

The MA-7As feature a built-in Bass Enhancer, which operates on psychoacoustic principles that converts low frequencies into a series of overtones the human ear cannot distinguish from the original low frequencies. This allows the listener to perceive bas frequencies outside of the normal range of the speaker cone, without overdriving the woofer. With the Bass Enhancer, the MA-7As provide a strong low-end in a very compact set of reference speakers. In addition the MA-7A's offer a Sub Out port to connect a subwoofer.

The MA-7As offer conveniently placed Volume and Tone controls. Adjust the volume and tone directly from the front of the speaker. While a large studio setup typically uses a mixer to control output level to the speakers, compact desktop setups can rarely afford the space a mixer requires. This is not an issue with the MA-7As. You can adjust your output volume and tone on the front of the speaker.

You can also connect two different sources directly into the MA-7As, allowing you to listen to audio from any two line-level sources. For example, you can have both your computer and your stereo connected to the MA-7As.

You can also plug headphones directly into the MA-7As. Plugging in headphones automatically defeats the speakers, allowing you to mix without disturbing others, and without having to disconnect anything in your setup.

The MA-7As are magnetically shielded for close proximity to your computer monitor.

SpankingVanillaice
02-14-2008, 03:58 PM
Here's a pic of the new monitors. Plus the RCA connections are gold plated so that's better than nickle plated ones that the M-Audio has. They also only use 22 watts of power and thay are Class B amp.


http://www.edirol.net/products/en/MA...image_04_L.jpg


http://www.edirol.net/products/en/MA...image_05_L.jpg


http://www.edirol.net/products/en/MA...image_06_L.jpg

hifitommy
02-22-2008, 08:37 PM
dont go for power consumption, go for sound. the amount of power we are talking about is miniscule to start with. refrigerators and heaters use WAY more than audio equipment.

for unpowered speakers, the class d amps to look at are channel islands audio d200s and spectron musician. google those and read the reviews. also, the absolute sound forum has a subject on class d amps:

http://forums.avguide.com/viewforum.php?f=91&sid=9948b1b1646e74f87adebff0348b4981

that should provide enough reading on the subject for quite a bit of your time.

my friend has cia d200s. i had heard them on $60k von schweickert speakers and was dumbfounded that speakers of that price could sound so good at such loud levels for an amp costing $2300 for 200wpc!!!

SpankingVanillaice
02-23-2008, 03:56 PM
Well I actualy think the best sounding and the most power saving monitors are the M-Audio AV-20 since that use Class D and plus they sounded the best when I listened to them so I' am getting the AV-20 back and keeping those.

SpankingVanillaice
02-23-2008, 04:15 PM
I just got these headphones and they sound really flat and clear for the price. Coby CV-790.
They have 50mm neodymium drivers that's really great.

Here are some specs for these studio headphones.

http://www.cobyusa.com/?p=prod&prod_num_id=180&pcat_id=4009#features-tab

bobsticks
02-23-2008, 05:07 PM
These are the Professional Noise Cancelling CNS model from Campbell's...

http://www.wizkidzcreches.co.uk/images/tincans.jpg

SpankingVanillaice
02-23-2008, 05:42 PM
I know one thing for sure is that I will save money keeping the M-Audio AV-20 and keeping the Coby CV-790 studio headphones. Plus both the headphones and monitors sound really good and clear as pro. :)


Here is a PDF file for more details for my new headphones.

http://www.cobyusa.com/files/specsheets/CV790_SP.pdf

SpankingVanillaice
02-23-2008, 05:57 PM
These are the Professional Noise Cancelling CNS model from Campbell's...

http://www.wizkidzcreches.co.uk/images/tincans.jpgWhat is that??? What does that have to do with my new monitors and headphones??? Sometimes I just don't understand you guys when you post something like this. :confused5:

SpankingVanillaice
02-23-2008, 07:56 PM
Here are some specs that are not posted on Coby's website. I found these on the box that my new headphones were in.




Driver Units.............. 50mm Super Thin Diaphragm

Impedance............................... 40 Ohms +/- 10%

Sensitivity.................................. 115 dB at 1KHz

Frequency Response.................. 20 - 22,000 Hz

Cord Length......................................... 2 meter