Please explain to me

jahjahlove

jahjahlove

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Joined
Mar 17, 2015
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PARIS FRANCE
Hi everyone,

I have a question regarding amplifiers:

I bought some months ago a Crown CDI drivecore 4 300 amplifier. I wanted this amp for two reasons: its power in order to move the 15" of my JBLs, and also because this amp integrate a DSP, capable of room correction, active bi amping, etc... I wrote earlier in the forum the benefits I was expecting from such an amp driven in wifi by Audio Architect.

So I spent some month with it now; if I was not flushed by the sound quality, i was intellectually interested in its DSP possibilities, and its simplicity of use.
Recently I plugged back my MC275, and realised how better was the Mc at doing bass. I am not talking about timbers quality in the medium or highs, my question is only about bass, and here it is:

How come a 75W amp can do more and better bass than a 300W amp with a nice Harman room curve implemented in it ?!

If someone has a technical explanation to help me understand, it would be nice.
I know I am comparing orange and apple, being tube and class D, but a volt is a volt and a Watt is a Watt, ain it ?

David
 
jahjahlove said:
Hi everyone,

I have a question regarding amplifiers:

I bought some months ago a Crown CDI drivecore 4 300 amplifier. I wanted this amp for two reasons: its power in order to move the 15" of my JBLs, and also because this amp integrate a DSP, capable of room correction, active bi amping, etc... I wrote earlier in the forum the benefits I was expecting from such an amp driven in wifi by Audio Architect.

So I spent some month with it now; if I was not flushed by the sound quality, i was intellectually interested in its DSP possibilities, and its simplicity of use.
Recently I plugged back my MC275, and realised how better was the Mc at doing bass. I am not talking about timbers quality in the medium or highs, my question is only about bass, and here it is:

How come a 75W amp can do more and better bass than a 300W amp with a nice Harman room curve implemented in it ?!

If someone has a technical explanation to help me understand, it would be nice.
I know I am comparing orange and apple, being tube and class D, but a volt is a volt and a Watt is a Watt, ain it ?

David
Click to expand...

Not a technical explanation, other than the parts used are generally junk. But quite frankly, in my opinion, Crown amps stink.
 
Speedskater said:
I suspect that if you measured the frequency response curve and the THD curve at the loudspeaker terminals, that they would be very different amp to amp.
Click to expand...


Hi
I cannot measure the THD but I surely measured the FRC with REW (thats how I check my correction is correct and the room curve I want implemented) and the answer is not there... I can produce both graph if you want....
 
kiwi_1282001 said:
Yes! The lack of standardization in the measurement of power can also mislead many. Crown's power rating is at 0.5% distortion (considered high) and for a short 500mS duration because it possibly explodes after that.:roflmao:
Click to expand...

besides, any amp even the shitiest is regarded as "perfect" in term of distortion compared to any speakers-room interaction...
 
All amps are not created equal. I have a Parasound A21 that has way better specs than my Pass X250, including a dampening factor greater than 1000, very fast slew rate and more peak amps than the Pass X250. The dampening factor of the Pass is 150. On paper the A21 specs out to be the better amp. The Pass blows the A21 out of the water in terms of sound quality and bass. Both amps are 250 wpc at 8 ohms.

To quote Papa John's pizza vs Pizza Hut "better ingredients, better pizza".
 
Sure ! I had this parasound one week and gave it back.

Behind my question was two points:
first: is there one or few parameters that would tell this amp is better at doing bass than another, or are we condamned to listen to every one of them, one by one ? (voltage capacity ? , don t know how to translate this...sorry) behind mcintosh very good autoformers...
second : can we get out of esotheric considerations (purely subjective and mystical thoughts), cause indeed the engeneers, for being scientific people, do not rely on paranormal activity to make their porduct...indeed good luck in design or component is welcome, just like in every domains, but just like people making spaceships, they do not regard poetry as their first source for doing so....
sorry for my english tonight kind of tired....
 
Well, to leave subjective would be to forget your question. Meaning, "better bass" is subjective to the listener. What I think is good bass may be different from yours. I like my bass to have authority yet be detailed. I don't want bass to bloom so much I can't tell the kick drum from the string bass.

If the Mac bass is better you may just like the thicker texture the Mac generally has. I can't speak to the Crown never hearing one.

Maybe we should talk about why you think the 275's bass is better. Will the 275 bass hit you in the chest, does the Crown?

And, yes, most of the time we just have to listen. Specs on paper generally aren't worth the paper written on. However, a safe bet is high current and large power supply. Even then one amp may exhibit different bass character from another.

jahjahlove said:
Sure ! I had this parasound one week and gave it back.

Behind my question was two points:
first: is there one or few parameters that would tell this amp is better at doing bass than another, or are we condamned to listen to every one of them, one by one ? (voltage capacity ? , don t know how to translate this...sorry) behind mcintosh very good autoformers...
second : can we get out of esotheric considerations (purely subjective and mystical thoughts), cause indeed the engeneers, for being scientific people, do not rely on paranormal activity to make their porduct...indeed good luck in design or component is welcome, just like in every domains, but just like people making spaceships, they do not regard poetry as their first source for doing so....
sorry for my english tonight kind of tired....
Click to expand...
 
Thanks for joining in.

Mr Peabody said:
Meaning, "better bass" is subjective to the listener. What I think is good bass may be different from yours. I like my bass to have authority yet be detailed. I don't want bass to bloom so much I can't tell the kick drum from the string bass.
Click to expand...
See, we have the same definition, walking slowly together toward objetivity... One can come here and declare to like muddy shallow bass...one can come here and declare to not like bass at all ...of course its their right and have to be respected...as individuals... but their opinion might seems ridiculous or absurd or reflect their poor hearing or bad taste! In the mean time all the manufacturers declare their new unit come closer and closer to what we can here in concert... which could serve as a reference....


Mr Peabody said:
If the Mac bass is better you may just like the thicker texture the Mac generally has. I can't speak to the Crown never hearing one.
Click to expand...
I called a tech i respect in France to get an explanation..; he didn't really produce one suprisingly enough to me... he said the Mc must have a bump in the low mids and that is what you hear and like... The FRC doesn't show that at all... I must say here that I never expected the Crown to outperform the Mc, not for half a second!
but if I was to do a metaphore with car, it s like the 75 HP Mcintosh has a better torque than the 300 HP Crown, so it beats it in the 0-60 MPH range... not really seen in real cars.... Indeed a Lotus for instance being very light manage to outperform say the ecoboost Mustang with only 160 HP in straight line ! not mentioning turns....But that the Mc could do better on a 10 or 12" driver why not but on a 15" woofer....

Mr Peabody said:
Will the 275 bass hit you in the chest, does the Crown?
Click to expand...
yes ! that is what suprised me ! the mc hit me in the chest... but to come back to car metaphore it is NOT like the Crown is say an Audi A5 and the mc a fun sports car of the 70s....the crown is clean and boring, but the mc is not trashy or dirty....(and certainly does not smell gaz (just kidding)

Mr Peabody said:
And, yes, most of the time we just have to listen. Specs on paper generally aren't worth the paper written on. However, a safe bet is high current and large power supply. Even then one amp may exhibit different bass character from another.
Click to expand...

yes large power current I think you got it right.... There is Mcintosh underating their 275 that has been measured at 100 W if I am correct (just like my Honda civic, i must stop with this car thing!), and yes Crown, like many others, might exagerate their specs!

Anyhow the Crown goes for sale from today, and that's the end of my adventure with class D (not with DSP though).
I sold My C22 (commemo edition) yesterday, and with some other unit I was keeping I might give it a try with the 4B3...
I haven't made enough money to purchase the dear ML you have and we talked about previously here....
A bit sick to reed here people talking about lamborghini and ferrari all the time when all I can do is my Civic... that i love by the way and this is the most important....god damn it! cars again!
 
This has been a fun thread to read.

I also have the MC 275 along with some other McIntosh amps like the MC 602 (a beast!) and the MC 2301. I have owned a bunch of other amps, mostly solid state. The MC 275 has a sound of its own. It is colored, but I think in a good way! If you like it, stick with it as you won’t find an amp, solid state or tube, that sounds just like it.

To your original question, I do not know what objective characteristics make the MC 275 sound like it does subjectively. My guess is the usual
measurements don’t tell the story.
 
jahjahlove said:
Hi everyone,

I have a question regarding amplifiers:

I bought some months ago a Crown CDI drivecore 4 300 amplifier. I wanted this amp for two reasons: its power in order to move the 15" of my JBLs, and also because this amp integrate a DSP, capable of room correction, active bi amping, etc... I wrote earlier in the forum the benefits I was expecting from such an amp driven in wifi by Audio Architect.

So I spent some month with it now; if I was not flushed by the sound quality, i was intellectually interested in its DSP possibilities, and its simplicity of use.
Recently I plugged back my MC275, and realised how better was the Mc at doing bass. I am not talking about timbers quality in the medium or highs, my question is only about bass, and here it is:

How come a 75W amp can do more and better bass than a 300W amp with a nice Harman room curve implemented in it ?!

If someone has a technical explanation to help me understand, it would be nice.
I know I am comparing orange and apple, being tube and class D, but a volt is a volt and a Watt is a Watt, ain it ?

David
Click to expand...

Class- D amplifiers have never had good bass , well none i have heard vs A/AB amps, sinking RMS current necessary for good bass is not their forte. This is pretty obvious when you look at a 20hz squarewave produced by a class-D amp ..

There is also the higher Damping factor at work too...
 
W9TR said:
This has been a fun thread to read.

I also have the MC 275 along with some other McIntosh amps like the MC 602 (a beast!) and the MC 2301. I have owned a bunch of other amps, mostly solid state. The MC 275 has a sound of its own. It is colored, but I think in a good way! If you like it, stick with it as you won’t find an amp, solid state or tube, that sounds just like it.

To your original question, I do not know what objective characteristics make the MC 275 sound like it does subjectively. My guess is the usual
measurements don’t tell the story.
Click to expand...


My guess is that would be wrong ...,



Regards
 
Just curious if you thought the 275 had a good bass response? Or, maybe it's just the overall balance of the amp.

Max has, or is, putting out a modern 275. The 275 has always been well regarded.

It was the Mac kilowatt monoblocks that gave me a new opinion of B&W flagship Nautilus. I've always heard them with ARC and Classe which never really done much for me. The Max mono's driving them had unbelieveable bass. I can't remember how well the detail was, I was so astounded at the difference in sound of the B&W, that's what stuck with me. I kept looking around the room, this guy has to have a sub stashed somewhere, LOL

W9TR said:
This has been a fun thread to read.

I also have the MC 275 along with some other McIntosh amps like the MC 602 (a beast!) and the MC 2301. I have owned a bunch of other amps, mostly solid state. The MC 275 has a sound of its own. It is colored, but I think in a good way! If you like it, stick with it as you won’t find an amp, solid state or tube, that sounds just like it.

To your original question, I do not know what objective characteristics make the MC 275 sound like it does subjectively. My guess is the usual
measurements don’t tell the story.
Click to expand...
 
My impression is the opposite, that Class D generally does good bass. The Class D bass is typically controlled with detail opposed to thick woolly bass. Odd, as well, if Class D doesn't do bass that they would be used in the majority of subwoofers.

If not good bass, I have to wonder what Class D's forte is as it certainly wouldn't be the smooth enjoyable high end.

a.wayne said:
Class- D amplifiers have never had good bass , well none i have heard vs A/AB amps, sinking RMS current necessary for good bass is not their forte. This is pretty obvious when you look at a 20hz squarewave produced by a class-D amp ..

There is also the higher Damping factor at work too...
Click to expand...
 
jahjahlove said:
I have a question regarding amplifiers:

How come a 75W amp can do more and better bass than a 300W amp with a nice Harman room curve implemented in it ?!

If someone has a technical explanation to help me understand, it would be nice.
I know I am comparing orange and apple, being tube and class D, but a volt is a volt and a Watt is a Watt, ain it ?

David
Click to expand...

Hi David,

Now that you've got all the audiophile woo woo explanations (including Mr Wayne's very funny one - to a technically literate/non-audiophile), here's the physical reality one.:)
Lets; start with the amps. The Crown is an "amplifier". It's going to multiply whatever voltage you supply it. The output is simply going to be a louder version of the input, whatever that may sound like. Yes, the onboard DSP can add some "special effects", but that is limited to the frequency domain and a switchable/defeatable effect.
The Mac, while called an amplifier, is actually a near full time special effects processor. There is no "off" switch for the special effects. There are several measurable metrics that demonstrate this clearly..IF one understands the relation of the measurements to perception. Lucky you we have a full suite
Lets start with the output impedance, lowish for a tube amp, but still enough to create special effects
attachment.php

Your frequency response in the bass will be affected by the impedance rises of your loudspeaker (we'll get to those later).
So you will have measurably different intensity difference in the bass, though you are not going to be able to measure accurately in room with any gated system due to the low resolution of the time windowing at LF.
Atop that, there is distortion. THD is generally a very very poorly correlated to audibility metric...except in large, or very large doses, like this:
attachment.php

With any bass peaks at >moderate levels, which demand power from the amps, there will be transformer saturation and several % levels of THD. To your audiophile ears, this will not sound l"distorted", but more "fullness" and "weight" to the bass. Compared, an "amplifier", like the Class D (or AB, etc) Crown amp will certainly sound "thin". Simply bumping the bass a bit with the DSP cannot accurately mimic this special effect, because it is more non-linear and also dynamically variable with level.
Then, there's your JBL 4430 (crossover redone??), which has fairly high levels of bass distortion (Figure 15), albeit at a relatively high 100db/1m level. Couple that to the impedance <1kHz being higher than >1kHz and a heft peak at 50Hz (Figure 9). Coupled with the FR mods created by the output impedance referenced above, you have both intensity and distortion "enhanced" bass vs the amp (Crown in this case).
Lastly, there is taste, as in yours. As JGHolt aptly stated, most audiophiles don't use live unamplified as a reference, so someone preferring the sound of a Marshall or Fender "bass" as the reference is quite normal these days. Preference is preference, nothing to debate. Enjoy.;)

cheers,

AJ

Sorry, back to football now..
 

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Mr Peabody said:
My impression is the opposite, that Class D generally does good bass. The Class D bass is typically controlled with detail opposed to thick woolly bass. Odd, as well, if Class D doesn't do bass that they would be used in the majority of subwoofers.

If not good bass, I have to wonder what Class D's forte is as it certainly wouldn't be the smooth enjoyable high end.
Click to expand...

Not odd at all , convenience and cost , hence why so many subs on the market are avg at best ...


Regards
 
AJ Soundfield said:
Hi David,

Now that you've got all the audiophile woo woo explanations (including Mr Wayne's very funny one - to a technically literate/non-audiophile), here's the physical reality one.:)
Lets; start with the amps. The Crown is an "amplifier". It's going to multiply whatever voltage you supply it. The output is simply going to be a louder version of the input, whatever that may sound like. Yes, the onboard DSP can add some "special effects", but that is limited to the frequency domain and a switchable/defeatable effect.
The Mac, while called an amplifier, is actually a near full time special effects processor. There is no "off" switch for the special effects. There are several measurable metrics that demonstrate this clearly..IF one understands the relation of the measurements to perception. Lucky you we have a full suite
Lets start with the output impedance, lowish for a tube amp, but still enough to create special effects
attachment.php

Your frequency response in the bass will be affected by the impedance rises of your loudspeaker (we'll get to those later).
So you will have measurably different intensity difference in the bass, though you are not going to be able to measure accurately in room with any gated system due to the low resolution of the time windowing at LF.
Atop that, there is distortion. THD is generally a very very poorly correlated to audibility metric...except in large, or very large doses, like this:
attachment.php

With any bass peaks at >moderate levels, which demand power from the amps, there will be transformer saturation and several % levels of THD. To your audiophile ears, this will not sound l"distorted", but more "fullness" and "weight" to the bass. Compared, an "amplifier", like the Class D (or AB, etc) Crown amp will certainly sound "thin". Simply bumping the bass a bit with the DSP cannot accurately mimic this special effect, because it is more non-linear and also dynamically variable with level.
Then, there's your JBL 4430 (crossover redone??), which has fairly high levels of bass distortion (Figure 15), albeit at a relatively high 100db/1m level. Couple that to the impedance <1kHz being higher than >1kHz and a heft peak at 50Hz (Figure 9). Coupled with the FR mods created by the output impedance referenced above, you have both intensity and distortion "enhanced" bass vs the amp (Crown in this case).
Lastly, there is taste, as in yours. As JGHolt aptly stated, most audiophiles don't use live unamplified as a reference, so someone preferring the sound of a Marshall or Fender "bass" as the reference is quite normal these days. Preference is preference, nothing to debate. Enjoy.;)

cheers,

AJ

Sorry, back to football now..
Click to expand...

Hillarious as alway AJ , if only you actually understood anything you wrote . Please post up a square wave response of your favorite class D amp ..

explain. AWay ....

As to taste , enuff irony there in your post to build a bridge...



:)
 
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