Class D vs Class A or A/B amps..?

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Snatchman

Well-known member
Joined
Jan 17, 2005
Messages
665
Location
North Carolina (USA)
Hello..Question: I've been audtioning a pair of Equator D-8s monitors. Even though they sound good for now, something just doesn't " do it" for me. I know it takes time to learn speakers but I'm talking amplification. I also have a pair of NS-10s and an Alesis RA-100 ( atm) power amp. The D-8s are rated at 100 watts per speaker will the RA-100 is rated a 75 wpc @ 8ohms /100 wpc @ 4 ohms. I have them calibrated for 'bout 79-80 db at the mix position. When I play the D-8s and then play the NS-10/RA-100, the RA-100 plays at a louder volume/sounds bigger ( not bass tho,just louder) than the D-8s at a lower volume level..!..Could this just be the characteristics of the two designs or what..?..Thanks..
 
I've said this on here before - some of the worst and some of the best amps I have ever heard are class D.  The "class" tells you nothing about quality, it's is all about how it's done.

That said in your example you are not comparing amps you are comparing whole speaker systems, you can't tell anything about the amps alone in that case (if that is your goal).

 
don't forget to consider the passive design of the cabinets, the efficiency of the speakers, frequency linearity etc.
In my experience, the amps tend to be a factor of 10x better than most speaker drivers I see.
 
Snatchman said:
Hello..Question: I've been audtioning a pair of Equator D-8s monitors. Even though they sound good for now, something just doesn't " do it" for me. I know it takes time to learn speakers but I'm talking amplification. I also have a pair of NS-10s and an Alesis RA-100 ( atm) power amp. The D-8s are rated at 100 watts per speaker will the RA-100 is rated a 75 wpc @ 8ohms /100 wpc @ 4 ohms. I have them calibrated for 'bout 79-80 db at the mix position. When I play the D-8s and then play the NS-10/RA-100, the RA-100 plays at a louder volume/sounds bigger ( not bass tho,just louder) than the D-8s at a lower volume level..!..Could this just be the characteristics of the two designs or what..?..Thanks..
I must say your question got me somewhat puzzled.
"the RA-100 plays at a louder volume/sounds bigger ( not bass tho,just louder) than the D-8s at a lower volume level" seems a truism to me.
Could be simply a difference in sensitivity. The RA100's sensitivity is quite high, needing only 0.5V (-4dBu) for its rated output. In conjunction with the NS10's sensitivity of about 90dBspl@1W/1m, it shows it takes only about 35mV (-27dBu) to generate the aforementioned 80dBspl. Equator do not publish sensitivity figures, but it is very likely that it has lower sensitivity, i.e. it requires more voltage to produce the same spl.
IMO it's not related to the operating class of the amp.
 
Rob Flinn said:
I use Hypex UCD180HG for my main monitoring.  They sound really good to my ears

https://www.hypexshop.com/
Indeed, there are a number of very good sounding class-D amps (Lab Gruppen, Powersoft, Crown) but there is also a lot of crap, just like there are Mercedes and Lada's.
 
abbey road d enfer said:
Snatchman said:
Hello..Question: I've been audtioning a pair of Equator D-8s monitors. Even though they sound good for now, something just doesn't " do it" for me. I know it takes time to learn speakers but I'm talking amplification. I also have a pair of NS-10s and an Alesis RA-100 ( atm) power amp. The D-8s are rated at 100 watts per speaker will the RA-100 is rated a 75 wpc @ 8ohms /100 wpc @ 4 ohms. I have them calibrated for 'bout 79-80 db at the mix position. When I play the D-8s and then play the NS-10/RA-100, the RA-100 plays at a louder volume/sounds bigger ( not bass tho,just louder) than the D-8s at a lower volume level..!..Could this just be the characteristics of the two designs or what..?..Thanks..
I must say your question got me somewhat puzzled.
"the RA-100 plays at a louder volume/sounds bigger ( not bass tho,just louder) than the D-8s at a lower volume level" seems a truism to me.
Could be simply a difference in sensitivity. The RA100's sensitivity is quite high, needing only 0.5V (-4dBu) for its rated output. In conjunction with the NS10's sensitivity of about 90dBspl@1W/1m, it shows it takes only about 35mV (-27dBu) to generate the aforementioned 80dBspl. Equator do not publish sensitivity figures, but it is very likely that it has lower sensitivity, i.e. it requires more voltage to produce the same spl.
IMO it's not related to the operating class of the amp.
Hello..Thanks for your reply..May be the sensitivy but I would 've thought with the D-8s, with power supply built on board, having a bigger amp rating would 've been louder at the same voulume setting..Though I'm no expert at this at all, I do sense a pretty variable difference in volume. Sure, I could just turn the D-8s up to match.. ;) the Ra-100, I was just curious could this be in the amp designs..All said and done, I may just sell the D-8s and get me another amp/speaker combo..Any suggestions..?
 
Snatchman said:
abbey road d enfer said:
Snatchman said:
Hello..Question: I've been audtioning a pair of Equator D-8s monitors. Even though they sound good for now, something just doesn't " do it" for me. I know it takes time to learn speakers but I'm talking amplification. I also have a pair of NS-10s and an Alesis RA-100 ( atm) power amp. The D-8s are rated at 100 watts per speaker will the RA-100 is rated a 75 wpc @ 8ohms /100 wpc @ 4 ohms. I have them calibrated for 'bout 79-80 db at the mix position. When I play the D-8s and then play the NS-10/RA-100, the RA-100 plays at a louder volume/sounds bigger ( not bass tho,just louder) than the D-8s at a lower volume level..!..Could this just be the characteristics of the two designs or what..?..Thanks..
I must say your question got me somewhat puzzled.
"the RA-100 plays at a louder volume/sounds bigger ( not bass tho,just louder) than the D-8s at a lower volume level" seems a truism to me.
Could be simply a difference in sensitivity. The RA100's sensitivity is quite high, needing only 0.5V (-4dBu) for its rated output. In conjunction with the NS10's sensitivity of about 90dBspl@1W/1m, it shows it takes only about 35mV (-27dBu) to generate the aforementioned 80dBspl. Equator do not publish sensitivity figures, but it is very likely that it has lower sensitivity, i.e. it requires more voltage to produce the same spl.
IMO it's not related to the operating class of the amp.
May be the sensitivy but I would 've thought with the D-8s, with power supply built on board, having a bigger amp rating
The D8's are rated at 100W, just like your RA100. OTOH, the RA100 has high sensitivity, which allows using it with semi-pro equipment (-10dBv) that does not have high output capability, and the D8's are designed for a more consistent operation, where nominal level is +4dBu.
 
abbey road d enfer said:
Snatchman said:
abbey road d enfer said:
Snatchman said:
Hello..Question: I've been audtioning a pair of Equator D-8s monitors. Even though they sound good for now, something just doesn't " do it" for me. I know it takes time to learn speakers but I'm talking amplification. I also have a pair of NS-10s and an Alesis RA-100 ( atm) power amp. The D-8s are rated at 100 watts per speaker will the RA-100 is rated a 75 wpc @ 8ohms /100 wpc @ 4 ohms. I have them calibrated for 'bout 79-80 db at the mix position. When I play the D-8s and then play the NS-10/RA-100, the RA-100 plays at a louder volume/sounds bigger ( not bass tho,just louder) than the D-8s at a lower volume level..!..Could this just be the characteristics of the two designs or what..?..Thanks..
I must say your question got me somewhat puzzled.
"the RA-100 plays at a louder volume/sounds bigger ( not bass tho,just louder) than the D-8s at a lower volume level" seems a truism to me.
Could be simply a difference in sensitivity. The RA100's sensitivity is quite high, needing only 0.5V (-4dBu) for its rated output. In conjunction with the NS10's sensitivity of about 90dBspl@1W/1m, it shows it takes only about 35mV (-27dBu) to generate the aforementioned 80dBspl. Equator do not publish sensitivity figures, but it is very likely that it has lower sensitivity, i.e. it requires more voltage to produce the same spl.
IMO it's not related to the operating class of the amp.
May be the sensitivy but I would 've thought with the D-8s, with power supply built on board, having a bigger amp rating
The D8's are rated at 100W, just like your RA100. OTOH, the RA100 has high sensitivity, which allows using it with semi-pro equipment (-10dBv) that does not have high output capability, and the D8's are designed for a more consistent operation, where nominal level is +4dBu.
Hello..Thanks again for your time..Ok I see now..I'll probably still just sell the D-8s tho..!
 

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