damping factors

[deltadube]

anyone know what the damping factor is on

xpa 1

xpa 3

what does the damping factor of an amp do?

thanks

[garbulky]

It shows how resistant it is to moisture. For instance an xpa-1 will endure a light drizzle as long as it's off vs a tube amp with a low damping factor which would probably not glow after a brief shower. Very useful on those late night hurricane parties.
(I am joking of course)
It's something to do with control of the speaker or feedback from the circuit. I'm a little hazy on the details. Rest assured that the xpa and UPA amps all have damping factors that are considered sufficient and tend to be higher than tube gear.

[audiohead]

garbulky is right about the EMO's amps haveing good Damping but more is better we want more,less is not good we always want more we gotta have more!!!Big Dan has given us More,power more watts Lots more amps more Damping did I say more of everything?Big Dan is right up there like a Rock Star in my book!and he gets 5 Stars too!Dats my review on Big Dan ;D!oh and Mr.Lonnie too ;D!If I had the bucks, I would have two of every amp he his just cause I know one day dem amps will be money in da bank!Just look how they are selling now even on EBay they don't stay long.Think about it say you have new EMO amps in the box unopen say you keep it for 10 years..say what!!Gold I tell ya! ;D ;D ;D..Top of Da Morning to ya Bob!

[Deleted]

Wikipedia is your friend!

"In loudspeaker systems, the value of the damping factor between a particular loudspeaker and a particular amplifier describes the ability of the amplifier to control undesirable movement of the speaker cone near the resonant frequency of the speaker system. It is usually used in the context of low-frequency driver behavior, and especially so in the case of electrodynamic drivers, which use a magnetic motor to generate the forces which move the diaphragm.

Speaker diaphragms have mass, and their surrounds have stiffness. Together, these form a resonant system, and the mechanical cone resonance may be excited by electrical signals (e.g., pulses) at audio frequencies. But a driver with a voice coil is also a current generator, since it has a coil attached to the cone and suspension, and that coil is immersed in a magnetic field. For every motion the coil makes, it will generate a current that will be seen by any electrically attached equipment, such as an amplifier. In fact, the amp's output circuitry will be the main electrical load on the "voice coil current generator". If that load has low resistance, the current will be larger and the voice coil will be more strongly forced to decelerate. A high damping factor (which requires low output impedance at the amplifier output) very rapidly damps unwanted cone movements induced by the mechanical resonance of the speaker, acting as the equivalent of a "brake" on the voice coil motion (just as a short circuit across the terminals of a rotary electrical generator will make it very hard to turn). It is generally (though not universally) thought that tighter control of voice coil motion is desirable, as it is believed to contribute to better-quality sound.

A high damping factor indicates that an amplifier will have greater control over the movement of the speaker cone, particularly in the bass region near the resonant frequency of the driver's mechanical resonance. However, the damping factor at any particular frequency will vary, since driver voice coils are complex impedances whose values vary with frequency. In addition, the electrical characteristics of every voice coil will change with temperature; high power levels will increase coil temperature, and thus resistance. And finally, passive crossovers (made of relatively large inductors, capacitors, and resistors) are between the amplifier and speaker drivers and also affect the damping factor, again in a way that varies with frequency."

This seems to indicate that the higher the damping factor, the better. However, kind of like THD measurements, you achieve a point of diminishing returns where higher damping factor is, simply, higher, not better. I have read where a damping factor over 200 is superfluous and is simply used by mfgrs. to describe a difference without a distinction...

-RW-

[garbulky]

Apr 15, 2013 6:08:02 GMT -5 audiohead said:

garbulky is right about the EMO's amps haveing good Damping but more is better we want more,less is not good we always want more we gotta have more!!!Big Dan has given us More,power more watts Lots more amps more Damping did I say more of everything?Big Dan is right up there like a Rock Star in my book!and he gets 5 Stars too!Dats my review on Big Dan ;D!oh and Mr.Lonnie too ;D!If I had the bucks, I would have two of every amp he his just cause I know one day dem amps will be money in da bank!Just look how they are selling now even on EBay they don't stay long.Think about it say you have new EMO amps in the box unopen say you keep it for 10 years..say what!!Gold I tell ya! ;D ;D ;D..Top of Da Morning to ya Bob!

Yep. Gotta love emo amps. I got my UPA-2 for around 300 new. What a DEAL. I don't think I've ever enjoyed my dollars more and longer than when I spent it on emotiva gear.

[audiohead]

Apr 15, 2013 7:43:29 GMT -5 garbulky said:

Apr 15, 2013 6:08:02 GMT -5 audiohead said:

garbulky is right about the EMO's amps haveing good Damping but more is better we want more,less is not good we always want more we gotta have more!!!Big Dan has given us More,power more watts Lots more amps more Damping did I say more of everything?Big Dan is right up there like a Rock Star in my book!and he gets 5 Stars too!Dats my review on Big Dan ;D!oh and Mr.Lonnie too ;D!If I had the bucks, I would have two of every amp he his just cause I know one day dem amps will be money in da bank!Just look how they are selling now even on EBay they don't stay long.Think about it say you have new EMO amps in the box unopen say you keep it for 10 years..say what!!Gold I tell ya! ;D ;D ;D..Top of Da Morning to ya Bob!

Yep. Gotta love emo amps. I got my UPA-2 for around 300 new. What a DEAL. I don't think I've ever enjoyed my dollars more and longer than when I spent it on emotiva gear.

Same here bro I was going too get a Parasound amp the A21 I just can't bring myself too part with $2,300 bucks when I can get the XPA-2 for a 1/3 of the price.The A21 is a nice amp but in my book way over priced by $1000 bucks oh wait yeah the Retail seller man gota eat too. ;D

[deltadube]

ive read damping factors over 1000 keep the rain out longer but also is an excellent rating for da sound..

how come emo dont show damping specs on all the amps instead of just a few?

still looking for da numbers for xpa 1 and xpa 3

cheers

[deltadube]

might as well ask for damping factor on the xpa 2 as well?

thanks

[Cory Cooper]

I think I remember reading somewhere that Lonnie had stated that the UPA/XPA amps have a damping factor of >200 1 kHz @ 8 ohms.

C

[GreenKiwi]

Keith had a post about damping factors. I don't remember the numbers exactly, but he effectively said what others have said. That above X it doesn't really do anything more and I think that their amps were designed to be about 1.5 * X or so.

[garbulky]

I've attached the unnoficial emotiva amp specs created by a user.

Attachments:

[DYohn]

A better source for audio information than Wikipedia is the Rane Reference Library: www.rane.com/digi-dic.html

They define damping factor as: damping factor Damping is a measure of a power amplifier's ability to control the back-emf motion of the loudspeaker cone after the signal disappears. The damping factor of a system is the ratio of the loudspeaker's nominal impedance to the total impedance driving it. Perhaps an example best illustrates this principle: let's say you have a speaker cabinet nominally rated at 8 ohms, and you are driving it with a Rane MA 6S power amp through 50 feet of 12 gauge cable. Checking the MA 6S data sheet (obtained off this website, of course), you don't find its output impedance, but you do find that its damping factor is 300. What this means is that the ratio of a nominal 8 ohm loudspeaker to the MA 6S's output impedance is 300. Doing the math [8 divided by 300] comes up with an amazing .027 ohms. Pretty low. Looking up 12 gauge wire in your handy Belden Cable Catalog (... then get one.) tells you it has .001588 ohms per foot, which sure ain't much, but then again you've got 100 feet of it (that's right: 50 feet out and 50 feet back -- don't be tricked), so that's 0.159 ohms, which is six times as much impedance as your amplifier. (Now there's a lesson in itself -- use big cable.) Adding these together gives a total driving impedance of 0.186 ohms -- still pretty low -- yielding a very good damping factor of 43 (anything over 10 is enough, so you don't have to get extreme about wire size). [Note that the word is damp-ing, not damp-ning as is so often heard -- correct your friends; make enemies.] "

[deltadube]

Apr 15, 2013 10:26:48 GMT -5 DYohn said:

A better source for audio information than Wikipedia is the Rane Reference Library: www.rane.com/digi-dic.html

They define damping factor as: damping factor Damping is a measure of a power amplifier's ability to control the back-emf motion of the loudspeaker cone after the signal disappears. The damping factor of a system is the ratio of the loudspeaker's nominal impedance to the total impedance driving it. Perhaps an example best illustrates this principle: let's say you have a speaker cabinet nominally rated at 8 ohms, and you are driving it with a Rane MA 6S power amp through 50 feet of 12 gauge cable. Checking the MA 6S data sheet (obtained off this website, of course), you don't find its output impedance, but you do find that its damping factor is 300. What this means is that the ratio of a nominal 8 ohm loudspeaker to the MA 6S's output impedance is 300. Doing the math [8 divided by 300] comes up with an amazing .027 ohms. Pretty low. Looking up 12 gauge wire in your handy Belden Cable Catalog (... then get one.) tells you it has .001588 ohms per foot, which sure ain't much, but then again you've got 100 feet of it (that's right: 50 feet out and 50 feet back -- don't be tricked), so that's 0.159 ohms, which is six times as much impedance as your amplifier. (Now there's a lesson in itself -- use big cable.) Adding these together gives a total driving impedance of 0.186 ohms -- still pretty low -- yielding a very good damping factor of 43 (anything over 10 is enough, so you don't have to get extreme about wire size). [Note that the word is damp-ing, not damp-ning as is so often heard -- correct your friends; make enemies.] "

great explaination thanks.. ok i with you upto

.186 ohms total driving impedance.. still pretty low eh..

but how did you get ? yeilding a good damping factor of 43?

( depends how hard its raining right)

thanks..

[DYohn]

Apr 15, 2013 11:14:09 GMT -5 deltadube said:

but how did you get ? yeilding a good damping factor of 43?

.

damping factor = loudspeaker nominal impedance divided by total amplifier output impedance. In the example from Rane, that would be 8 / 0.186 = 43 (rounded)

[deltadube]

ok i guess i got it 8 ohm nominal speaker impedance divided by the total driving impedance
( wire and amp ) 8 / .186 = 43 total damping factor

xpr 1 1000 with 8 ohm speaker .008 ohm and wire .1588 ohm equals
total driving impedance of .1668

so 8 / .1668 = 47.96 damping factor..

so if speaker goes down to 2 ohm during changes during music play back
you dipping down to the 12 area..

thanks

[deltadube]

anybody got the damping ratings for the

xpa 1 2 and 3

thanks

[DYohn]

Apr 15, 2013 11:31:34 GMT -5 deltadube said:

ok i guess i got it 8 ohm nominal speaker impedance divided by the total driving impedance
( wire and amp ) 8 / .186 = 43 total damping factor

xpr 1 1000 with 8 ohm speaker .008 ohm and wire .1588 ohm equals
total driving impedance of .1668

so 8 / .1668 = 47.96 damping factor..

so if speaker goes down to 2 ohm during changes during music play back
you dipping down to the 12 area..

thanks

Correct. And df > 10 is what you want. Also realize the impedance of the amplifier output and of the speaker wire also changes with frequency right along with the loudspeaker voice coil, so you cannot be completely certain of any of this as it constantly changes with signal frequency. As indicated in the Rane article, lower amplifier output impedance and lower speaker wire DCR (resistance) is generally better, although there is a point of diminishing returns where the difference due to slight improvements is meaningless to system performance.

[deltadube]

so the damping factor is really low in the bass notes.. from what ive seen on the curves
the ohms impedance drops alot in the speakers from like 8 to 4 ohms there what about
the wire does its impedance drop off too?

why do some amps limit the ohms impendance rating of speakers to like 4 or more? eg not
to run 2 ohm speakers on this amp..

so your saying instead of using 12 awg cable be better with 10 awg cable.. less impedance?

the cable is the biggest factor?

thanks

[audiohead]

Apr 15, 2013 10:26:48 GMT -5 DYohn said:

A better source for audio information than Wikipedia is the Rane Reference Library: www.rane.com/digi-dic.html

They define damping factor as: damping factor Damping is a measure of a power amplifier's ability to control the back-emf motion of the loudspeaker cone after the signal disappears. The damping factor of a system is the ratio of the loudspeaker's nominal impedance to the total impedance driving it. Perhaps an example best illustrates this principle: let's say you have a speaker cabinet nominally rated at 8 ohms, and you are driving it with a Rane MA 6S power amp through 50 feet of 12 gauge cable. Checking the MA 6S data sheet (obtained off this website, of course), you don't find its output impedance, but you do find that its damping factor is 300. What this means is that the ratio of a nominal 8 ohm loudspeaker to the MA 6S's output impedance is 300. Doing the math [8 divided by 300] comes up with an amazing .027 ohms. Pretty low. Looking up 12 gauge wire in your handy Belden Cable Catalog (... then get one.) tells you it has .001588 ohms per foot, which sure ain't much, but then again you've got 100 feet of it (that's right: 50 feet out and 50 feet back -- don't be tricked), so that's 0.159 ohms, which is six times as much impedance as your amplifier. (Now there's a lesson in itself -- use big cable.) Adding these together gives a total driving impedance of 0.186 ohms -- still pretty low -- yielding a very good damping factor of 43 (anything over 10 is enough, so you don't have to get extreme about wire size). [Note that the word is damp-ing, not damp-ning as is so often heard -- correct your friends; make enemies.] "

ABig Thank you Sir for this post!I now have to go shorten my L/R front speaker cables..I knew there was more too this Dampn-ing thing..But really thanks I found a Thread where on a HarmanKardon site the two where talking just about this everything too consider when Factoring the Damping of an amp.Your spot on Bro!

[DYohn]

Apr 15, 2013 13:32:55 GMT -5 deltadube said:

so the damping factor is really low in the bass notes.. from what ive seen on the curves
the ohms impedance drops alot in the speakers from like 8 to 4 ohms there what about
the wire does its impedance drop off too?

why do some amps limit the ohms impendance rating of speakers to like 4 or more? eg not
to run 2 ohm speakers on this amp..

so your saying instead of using 12 awg cable be better with 10 awg cable.. less impedance?

the cable is the biggest factor?

thanks

Amplifier load ratings have nothing to do with damping factor, they have to do with the maximum safe current the amp's output stage can handle without over heating a component. An amplifier rated into 2-ohms can safely supply more current than an amplifier rated at 8-ohms.

The impedance of speaker wire is generally several times the output impedance of any good quality amplifier, so yes it generally has a much greater impact on DF than the amp does, and 10 AWG is a bit less resistance (and impedance) than 12 AWG. But the difference is small and largely moot. Unless a system needs larger gauge wire due to power or cable run length, 14 AWG is really all that's required for most homes even with its higher resistance.

Now all that being said, damping factor is probably one of the least important criteria in how a system sounds, and like Rane says any DF > 10 will provide proper control of the woofer. A system with DF of 100 is "better" than a system DF of 20, but in practical application no listener will ever hear any difference between them if that's the only difference.