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Your favorite pro amps for powering L/C/R mains? - Page 2

post #31 of 129
Hey Rilla, when I move back this summer I could bring by an AudioSource Amp One (original made in USA back in early 1980's and not the Chinese crap they became), Adcom GFA 555, and an Odyssey Khartago (configured exactly like the one Stereophile gave rave review - for whatever that may be worth, in my view not much). Covers three different price points, but not the crazy high end voodoo mojo magic realm.
post #32 of 129
I'm with Guuurilla on this. I've been running two DTS10s for awhile and always wanted more ooomph out of the mains to keep up.

Had epq1200's running 250wRMS into the 8 Ohm SHO10s. It was great but later experimented and found more power made a huge difference. Now have three epx4000's running 530wRMS into 8 Ohm SHO's. The epx amps will later drive dual 10" towers when finished nicely at 4 Ohms each. One day, one day. For now it's definitely a better match for my setup with the new amps and more juice.

At one point we had a SHO10 hooked up to a receiver channel, another to a epq1200, and another to a epx4000. Powered, or connected one after the other to listen test. Would never go back to just receiver power that's just silly talk. biggrin.gif
post #33 of 129
Thread Starter 
Quote:
Originally Posted by A9X-308 View Post

The fans on my P7000S have only very rarely come on when running subs, hard. My P2500S, I've never heard the fans come on at all.
Very quiet electrically too. I've been running Yamaha pro amps in my PA for years now and have beaten the snot out of them and never broken one yet.

Thanks for the info, very helpful. cool.gif Slowly expanding my knowledge of other PA brands outside the "norm" here.

Quote:
Originally Posted by LTD02 View Post

if you haven't seen this old one, you might find it interesting:

http://www.matrixhifi.com/contenedor_ppec_eng.htm

inuke6000 bench test:

http://forum.speakerplans.com/behringer-inuke-nu6000-vs-kam-kxd7200-bench-tested_topic69202_page1.html

fun read on how a "golden ear" couldn't tell the difference of a $14000 pair of monoblocks vs. an cheap integrated amp.

http://www.hometheatershack.com/forums/home-theater-receivers-processors-amps/34084-can-we-really-hear-difference-between-amps.html

"The Editor at Hometheaterequipment.com picked up a few Crown XLS Drivecores on a lark to test on his B&W 800 Diamonds. Long story short: He dumped his Parasound 2250."

http://www.avsforum.com/t/1424367/amplifier-for-revel-salon2-for-10k-or-less/30

famous quote: “Any amplifier, regardless of topology, can be treated as a “black box” for the purpose of listening comparisons. If amplifiers A and B both have flat frequency response, low noise floor, reasonably low distortion, high input impedance, low output impedance, and are not clipped, they will be indistinguishable in sound at matched levels no matter what’s inside them. Of course, some of the new “alphabet soup” topologies do not necessarily satisfy those conditions.
I really believe that all this soul-searching, wondering, questioning, agonizing about amplifiers is basically unproductive and would be much more rewarding if applied to loudspeakers instead. For various reasons that I have discussed in the past, people are more willing to change amplifiers than loudspeakers. That’s most unfortunate because a new and better loudspeaker will change your audio life but a new amplifier will not.
—Peter Aczel, Editor & Publisher, The Audio Critic

http://www.hometheatershack.com/forums/home-theater-receivers-processors-amps/34084-can-we-really-hear-difference-between-amps.html#ixzz2NwiQPW7Y

as for how much power you need, work backwards.

if you are listening at 95db average (high listening level) to content with 20db peak to average, you need 115db at the listening position (uncompressed and unclipped). add some more to make up for losses due to distance from speakers and you need even higher. so if you want realistic dynamics of a drum set in a club sitting close to the stage, you might need a system capable of clean 130db peaks. so even with high sensitivity speakers, you can still encounter scenarios where hundreds if not thousands of watts of power are required.

basspig's system is 140db+ capable in the mid-bass for a reason. :-)
page 3 is a fun read: http://www.basspig.com/

Quote:
Originally Posted by A9X-308 View Post

^^ To add to the above, the famous Nouisaine/Zipser test. Starts end page pdf7.

Can't pick a Yamaha integrated from a Pass.

Awesome, awesome information, thanks LTD and A9X!! Exactly what I was looking for. biggrin.gif I had read the inuke6000 bench test many times but the others I hadn't seen yet. Figure if I'm really looking for 120-125 DB peaks (as a reference - still less than my subs are producing) at the LP 15 feet away it takes a bit more power than one would initially suspect. cool.gif
Quote:
Originally Posted by NWCgrad View Post

Hey Rilla, when I move back this summer I could bring by an AudioSource Amp One (original made in USA back in early 1980's and not the Chinese crap they became), Adcom GFA 555, and an Odyssey Khartago (configured exactly like the one Stereophile gave rave review - for whatever that may be worth, in my view not much). Covers three different price points, but not the crazy high end voodoo mojo magic realm.

Sounds good - where are you moving back to?
Quote:
Originally Posted by autox320 View Post

I'm with Guuurilla on this. I've been running two DTS10s for awhile and always wanted more ooomph out of the mains to keep up.

Had epq1200's running 250wRMS into the 8 Ohm SHO10s. It was great but later experimented and found more power made a huge difference. Now have three epx4000's running 530wRMS into 8 Ohm SHO's. The epx amps will later drive dual 10" towers when finished nicely at 4 Ohms each. One day, one day. For now it's definitely a better match for my setup with the new amps and more juice.

At one point we had a SHO10 hooked up to a receiver channel, another to a epq1200, and another to a epx4000. Powered, or connected one after the other to listen test. Would never go back to just receiver power that's just silly talk. biggrin.gif

Funny enough I believe it was you who got me started on this when you got me to hook up my SHO's to the EP4000. At reasonable volumes (<90db at the LP) they sounded the same but above that they had a lot more to give than I thought. I remain impressed with the SHO10's they are an excellent speaker.
post #34 of 129
Quote:
Originally Posted by autox320 View Post

At one point we had a SHO10 hooked up to a receiver channel, another to a epq1200, and another to a epx4000. Powered, or connected one after the other to listen test. Would never go back to just receiver power that's just silly talk. biggrin.gif

That's what I'm talking about! Some realtime A/B/C testing. More unreasonable power!

biggrin.gif

Rillz, you want to split the cost a FP10KQ just to throw it in the mix...lol
post #35 of 129
Quote:
Originally Posted by Gorilla83 View Post

As the title says, I'm looking to experiment with some different pro amps on my front stage. I'm currently running an EP4000 but would love to try something with built in DSP. The lower the noise floor the better as with the gains we're dealing with they seem to be very prone to picking up noise. I convert the unbalanced input of my receiver to balanced. I'm considering the following:

Inuke6000DSP - tried this on Sunday. Seemed to have a good deal of power, but very prone to picking up noise in the line, especially with higher gain settings. Damn thing just looks and feels like a toy but it does crank indeed.

Crown XTi2002 - Looks like a nice amplifier, have not used the DSP. A bit more pricey at 699, but likely a higher end (build quality) amp than the Behringer.

Anything from QSC worth looking at in this range? Peavey IPR series?

What are you guys running and what are your favorites? Price range (street price) 400-800 per amp would be a good range.

I've used XTi 2000s to drive subwoofers and found it easy enough to program the DSP to get the frequency response and crossover action that I desired. I presume that the XTi 2002 is no worse! ;-)

On the bench the XTi 2000 is a very clean Class AB-style amp. It is actually class G with a robust switchmode power supply.

Published tech tests suggest that the iNukes are maybe an order of magnitude or more dirtier, but probably not enough so to cause audible problems.
post #36 of 129
Thread Starter 
Quote:
Originally Posted by popalock View Post

Rillz, you want to split the cost a FP10KQ just to throw it in the mix...lol

That seems reasonable. biggrin.gif We have issues - confirmed.

Quote:
Originally Posted by arnyk View Post

I've used XTi 2000s to drive subwoofers and found it easy enough to program the DSP to get the frequency response and crossover action that I desired. I presume that the XTi 2002 is no worse! ;-)

On the bench the XTi 2000 is a very clean Class AB-style amp. It is actually class G with a robust switchmode power supply.

Published tech tests suggest that the iNukes are maybe an order of magnitude or more dirtier, but probably not enough so to cause audible problems.

I noticed that unique squared had XTI4000's on closeout previously for 589 shipped! Too bad they are all gone by now. Heck of a deal.
post #37 of 129
Quote:
Originally Posted by Gorilla83 View Post

Funny enough I believe it was you who got me started on this when you got me to hook up my SHO's to the EP4000. At reasonable volumes (<90db at the LP) they sounded the same but above that they had a lot more to give than I thought. I remain impressed with the SHO10's they are an excellent speaker.

Sure blame me smile.gif So you changed from the seos15's to the unity horns? Schweeeet!! I was looking to copy my dual 10 design off the yorkville E210, and then there's the TMM and MTM designs of JTR Noesis. I knew you'd like tower version's better to keep up with those subs lol. Power gives more mid punch but nothing beats displacement. I like my SHOs very much and yes they are more capable than most think. So much so that I bought and want to play with a dual 10 design myself. Have a pile of drivers and gear on my workbench but i'm back in the sandbox to contemplate it more.

You know actually during testing we pushed the center channel SHO real hard and my girl said it was making funny noises. All equip chain is gain structured with a SMD DD-1 to keep from clipping along the way. We took the speaker out and noticed some of the batting had fallen down blocking most of the slot vent lol. Folded the batting in a way that it won't happen again. Then checked the others to make sure they were good to prevent that.
BTW the eminence xover for the tweeter has a 1:3 compression lamps to protect from over driving so it's almost impossible. Now a fire might start from the lamps but that's another matter cool.gif The delta10a is one beef cake sob for a 10" driver. Can take plenty of power with duty cycle without overheating. Let ya know if we ever smoke one. biggrin.gif

Quote:
Originally Posted by popalock View Post

That's what I'm talking about! Some realtime A/B/C testing. More unreasonable power!
biggrin.gif

Rillz, you want to split the cost a FP10KQ just to throw it in the mix...lol

You bet. I figured the drivers we are using are way over rated for the tiny power most are putting on them. These are pro style drivers guys. I dabbled in the dj scene too and most know receivers power is a joke ie 100wRMS is child's play.

Ahhh the smell of warm coils after a movie eek.gif


Now that would be fun to see. Post when you smoke something.
There's always the wall outlet to see what it's made of lol
post #38 of 129
I will be moving to Frederick, MD. Not exactly next door, but not an aweful drive. I used to commute every Sunday from Frederick to Newport, RI (and back to Frederick on Friday), did this for nearly two years before the navy decided they needed me in Cambodia.
post #39 of 129
Quote:
Originally Posted by NWCgrad View Post

I will be moving to Frederick, MD. Not exactly next door, but not an aweful drive. I used to commute every Sunday from Frederick to Newport, RI (and back to Frederick on Friday), did this for nearly two years before the navy decided they needed me in Cambodia.

You are going to be about an hour from me. When do you move back?
post #40 of 129
Quote:
Originally Posted by zora View Post

Carvin's new DCM-X series seems interesting.

I've used Carvin's, QSC EX & MX, Yamaha's, Soundtech, Crest Prolite, and others for HT/Stereo speakers and can say that I really can't tell the difference between them and my "audiophile" amps.

Jim

You aught to see them over at Polk Audio... Whew. There is one guy that frequents both there and here and they convinced him to get an old Carver and refurbish it. I offered the next time I was in his neck of the woods to bring over a Crown XLS DriveCore and just got the parroted response of Pro-Amps don't sound good and I have my reasons for believing it but I won't really say why:rolleyes: This rube is into Kimber Kables too.
post #41 of 129
I second the reco on the Yamaha pro amps, big power, low fan noise in stock config ...

But, if I were dabbling into the pro amp market these days, with an eye on dsp, I'd look seriously into what Crest is offering. Their new pro-lite series (whatever it's called) looks like the goods. Yeah, it's not US built like their good stuff, but their cred is solid, and if it says Crest, I'd bet it would pass the test. The real question would be their -3dB point.

Good luck

btw, IMO, differences are often merely attributable to some non-linearity,maybe clipping onset. The peak demands are extraordinary when one examines the math.

10dB peak requires 10x power increase
20dB peak requires 100x
30dB peak requires 1000x

Quite the daunting task... hence the inherent level of capability oft associated with high sens/high power approaches. Dynamic material easily gobbles up amplifier headroom.



Here's Tom Danley on the subject;

[IHi guys

I have to run in a little bit but saw the words “ go deaf” and such and thought it would be important to clarify a couple things on that subject.

I think I mentioned this stuff to Brandon and Josh a while back so I hope they aren’t bored hearing the explanation again haha.

In audio, there is an expression “headroom is your friend” and I guess that is part of the message. What loudspeakers do wrong or non-linearly changes with level and the amount of misbehavior increases more rapidly than the level of the desired signal as you increase the operating level.

Well before a speaker burns out, it is severely compromised in it’s performance.
With the heating of the voice coil, one finds the SPL decreases relative to the expected level with increasing power, also the systems tuning / frequency response changes at the same time, for the same reason.
For “modern” drivers, this “power compression” begins about 1/8 of the drivers rated power, if rated using the AES procedure.

Honestly there is so much BS regarding specs and such in commercial sound that to add a sense of “realism” or something to that mess, we have a 3rd party laboratory specify usable rated power. Hifi, don't get me started.

When driven with a slowly increasing drive level, when the speakers response departs by 3dB from the expected response based on the input power and 1W response, that is the maximum usable power.
If you examine the CLF file with the CLF viewer, that is the number shown there, as well as other parts of the speakers performance.

Anyway, what we associate with “loud” music is often at least in part or even largely due to the departure from linear the speaker is exhibiting when driven hard. We have learned what “loud” speakers sound like, only in part through the actual SPL.

For this reason, a very clean linear speaker producing music at the same measured SPL, may sound much less loud than another speaker that is straining.
We hear “loudness” in part through the spectrum we are exposed to, distortion itself is the production of “extra” harmonics not part of the music, “free energy” so to speak which occupies a larger spectrum than the original signal.

On the other hand we have sound pressure that you measure and here to the situation is less than ideally clear also.
In the old days of analogue tape it was critical to have a way to set the recording level.
This was done by a VU meter (Volume Unit), usually a meter movement with markings and a red “don’t go much past here” marks.
When done properly, this represented a realistic limit.

The funny thing is, what you measure depends on how long a time you examine.
If you use a fast reading sound level meter, you are integrating the SPL for some period of time and arrive at short time average SPL.
Set the meter to “slow” and obviously the meter moves a lot less and the peaks and dips are much smaller, integrated for a longer time. So, what we hear as loudness is also in part related to how long the sound is.

Most people think about loudness this way, what the sound level meter says.

Actually while useful measurements, these do not tell you what is really happening either if that is your interest.
If you take the microphone Voltage signal and it’s root sensitivity and you examine that signal on a storage oscilloscope, you can work backwards to the peak SPL, the actual loudness at that instant in time, NOT at all what it might sound like.

If you have a peak hold reading sound level meter (not common but I have one) you would find that in your home, you can produce very intense short sounds and very intense very low frequency sounds. I found that dropping a spoon on the floor could produce peak levels in the 130’s and sitting in car and closing the door produced a peak in the 140’s.

You never see anything like that with a normal Sound Level meter because these sounds are too short or low to sound “loud” or be indicated as significant.
Modern reproduction systems are not usually geared around the short term peak requirements but a slower lower average.

About 10 years ago, I was part of a ABX blind listening test comparing a number of Pro-sound amplifiers. I was using some early time coherent speakers I had designed for the company and as a sanity check, brought in two hifi amplifiers, one being a Threshold Stasis.
The amplifiers did not all sound the same, after searching recordings I found a couple parts where one could reliably hear differences, not in anything obvious BUT oddly in the decay parts of the sounds.

Anyway at a modest level (peaks about –15 –20dB on the Thresholds “fast” meter, it began to be “different” in a different way, it sounded slightly less dynamic.
I was very puzzled (it was my listening amp at home) and grabbed an oscilloscope and examined the outputs. Sure enough around the point it began to sound less dynamic, it had reached instantaneous clipping.

TO BE CLEAR this is nothing like “clipping” which everyone knows, this was ONLY detectable if one had a “without” version to compare to (in this case from a much larger amplifer).
By it self, it sounded fine, no problems and that “not hearing” the problem is exactly why most sound level meters and other volume level indicators do not show the peak requirements.

Anyway, my point (looking at the clock) it that to preserve or realistically reproduce sounds, you often need a far larger peak level than you would ever guess based on the ubiquitous Sound level meter. Of course all of this is irrelevant if your producing near steady tones, I am talking about dynamics.
You simply can’t produce short large peaks unless the system can produce them at all in the first place. Headroom is your friend.

This interest in making things sound real is also why I fiddle with recording too, recording with no compression. I have a pair of TH-50’s and SH-50s in my system with enough power to be somewhat embarrassed to mention and at a level that is still ‘not that loud”, I can reach instantaneous clipping with the fireworks recording.
I have not had a problem with any movie sound track however.

I am trying to decide if I am going to re-arrange everything so I can get these guys worked in and retire the TH-50’s.
I suspect I will have to listen to another round of my kids saying “DAAAAD are you playing that fireworks thing again!!!” But they love watching movies on it when the TH-50's were put in haha.
Got to run,
Best,
Tom Danley
][/I]


Good luck
post #42 of 129
QSC are loud , you need to change the fans.

I too running 3 yamaha. 2 (p3500s) 1 (p2500). THese are nice amp and quiet.
post #43 of 129
Thread Starter 
post #44 of 129
I have an xls-1500 running my f20s and it sounds great/is dead silent.
post #45 of 129
^^ Noise floor is fairly irrelevant for subs, but very important for full range speakers as the area where we're most sensitive and likely to detect noise is several octaves above the sub range, ie 2-5kHz.
post #46 of 129
I would like to get some info on the drivecore's rolloff down low.
post #47 of 129
I just hooked up one of Jonathan's amps he let me borrow, the Crown xls 802. I've been listening for the last 30 minutes or so every once in awhile cranking it up pretty loud. I swear I can tell a difference but I'm not going to believe myself until I can do it blind.

There is some hiss which is very noticeable from a couple feet from the speakers. From my LP you can just barely hear the hiss if you have no signal and you are really listening for it. Still... I think that would bug me over time. The hiss is the same volume no matter what the master volume is set at.

Turning the amps gain all the way up gave me the same output that the receiver amp did when level matching with the other speakers.
post #48 of 129
^
Really shouldn't have any hiss that can be heard unless ear is right next to speaker. I had hissing for the longest and swore there was nothing could do to eliminate it but finally got it to go away with cable management. I can now turn my plx3602's gain all the way up and stick my ear next to the LCRs and not hear anything.
post #49 of 129
It's more of a hiss/buzz thing. So just try to separate the cords from each other? I'll try it when I get a chance.
Edited by carp - 5/2/13 at 4:54pm
post #50 of 129
Man, I swear I can tell a difference. I went into this thinking I would not hear a difference too...

Can't wait to test it blind. Man this is a sweet/smooth sound when I get on the volume... this has placebo written all over it. redface.gif
post #51 of 129
Man it was like voodoo to me. I tried cable management in two different rooms and couldn't get it to go away then one night I started messing with wires and cables in the back of my rack trying to get a hum out of my subs and it disappeared from my LCRs. I don't know if a cable was too close to a power wire or what but I have eliminated it every since then.

And I can tell a difference with my T8s powered by 4311 and 3602 for sure! You should be able to blindly tell the difference especially after getting used to hearing the amp power them and taking it away.
post #52 of 129
On the "how much power is enough power" front -- after listening to my U15's on receiver power (Emotiva DMR-1, 125 wpc into 8 ohms/??? into 4 ohms) for many months, it was apparent that there was PLENTY of juice to get them stupid-loud...but upon switching over to the biggest QSC I have (a DCA3022 @ 900 wpc into 4 ohms), there is something to be said for the iron grip control that a big amp has on the speaker cones. The bigger amp just has more 'drive' and 'pop' to the sound, even below reference. Some of this could be because the Emo might not be providing adequate 'nuttage' into the 4-ohm load. I'm hoping that my 400 wpc 4-channel model gets close enough to it's big brother. smile.gif

If you don't have a problem going used, the QSC PLX/CX/DCA amps are worthy contenders. QSC makes a nice DSP (either DSP-3 or DSP-4) that plugs right into the back of the DCA, CX, and some PowerLight 2 models. If you time it right, these DSP's can be had on eBay for $100-$200 (even seen a few DSP-3's go under $100).
post #53 of 129
Quote:
Originally Posted by FOH View Post


The peak demands are extraordinary when one examines the math.

10dB peak requires 10x power increase
20dB peak requires 100x
30dB peak requires 1000x

Quite the daunting task... hence the inherent level of capability oft associated with high sens/high power approaches. Dynamic material easily gobbles up amplifier headroom.

Exactly why the difference between 300 watts and 500 watts is nearly negligable. The only way to get meaningful change, is to change the amount of power by orders of magnitude. Double the power is 3db. 3db is audible, but not very. To see 10db difference, you gotta be talking about going from 300 watts to 3000watts.

Now, I should openly state/admit that I don't have much experience with big amps in my own home. I've just never bothered to spend the money. But I do have a variety of amps. The biggest difference I usually experience has to do with input sensitivity than anything. I have one amp in particular that sounds crazy powerful. Just blasts my speakers in a very gripping, fun way. Sounds incredible. Guess what, it's a whimpy 30 watts. Meanwhlie my 200 watt crown sounds lame compared to it. The truth is though, it's because I FEEL good only turning up my receiver to -30 with the 30 watter and FEEL weird turning it up to -15 with the 200 watter. It should be the other way around right? You bet there's more power in the crown, but the input sensitivity makes it FEEL less powerful. If I didn't know any better, and I was blind, I might pick the smaller amp. All because it has really high input sensitivity.

You know all this FOH, just saying it.
post #54 of 129
I was actually testing a few different pro amps for mains. I tried a older crest v1500- great sub amp , mains to bright at high volume. Qsc rmx2450 decent bass , to bright on top end, ep2500 -good bass-a little warmer , best sounding at high volume levels. Speakers tried with these amps were polk rta15tl's,polk rt55i's, jbl l220's,
jbl 4652's,jbl L7's , cerwin vega dx9's sold now.
post #55 of 129
The amount of sound power asked of a speaker at reference can be daunting. Forget about 87dB sensitive leakers giving you reference level in a mid-size, well treated room.

Each channel is asked to provide 105dB at the listening position. Add 12dB for a listening position about 12 feet away. Add 9-10dB for the headroom Audyssey and other room correction algorithms can (and do, if unchecked) gobble up. That's 126dB, or over 1000W into a 95dB sensitive speaker.

For the sub it is both better and worse. With bass management, a 7.1 soundtrack can ask for over 125dB (and as much as 128dB) instantaneous peaks from your sub at the listening position (yes, it does happen: Star Trek, Immortals, Skyfall have). Many films ask for 119 or 120dB peak RMS levels (Transformers 2, The Dark Knight Returns). Fortunately, room gain and some modes can help, but trying to correct dips in freq response will eat up headroom.

I have two ~95dB sensitive folded horns (100dB in room), each w/ 500W going to them. That's approx 106dB with each receiving 1 Watt, and I get around 98dB at the MLP with 1W in. They have around 27 more dB left in them with them at full tilt, for a grand total of 124dB, before EQ robs more headroom, and some LF boost to get flat to 15Hz is added. I can only listen at 10dB below Reference to keep the sound clean......with two THTs! I cannot feed them more power: they are excursion limited unless I highpass them due to the LF boost I apply.

Like many say and have said here, headroom is your friend....I get a laugh out of folks thinking that their 87-88dB 'HiFi' speakers and single 12 or 15" sub are giving them 'Reference Level' with AVR power.....but I distinctly remember a time when my system was just that, and at the time, I thought it was awesome.....but I used to listen at -17 to -20dB when playing 'loud'...

Remember, if you calibrate for reference level with noise and SPL meter before EQ, it is picking up the SPL of the largest peak in your response, and the rest of the freq bands may be limited in SPL.....

JSS
post #56 of 129
Quote:
Originally Posted by maxmercy View Post

The amount of sound power asked of a speaker at reference can be daunting. Forget about 87dB sensitive leakers giving you reference level in a mid-size, well treated room.

Each channel is asked to provide 105dB at the listening position. Add 12dB for a listening position about 12 feet away. Add 9-10dB for the headroom Audyssey and other room correction algorithms can (and do, if unchecked) gobble up. That's 126dB, or over 1000W into a 95dB sensitive speaker.

For the sub it is both better and worse. With bass management, a 7.1 soundtrack can ask for over 125dB (and as much as 128dB) instantaneous peaks from your sub at the listening position (yes, it does happen: Star Trek, Immortals, Skyfall have). Many films ask for 119 or 120dB peak RMS levels (Transformers 2, The Dark Knight Returns). Fortunately, room gain and some modes can help, but trying to correct dips in freq response will eat up headroom.

I have two ~95dB sensitive folded horns (100dB in room), each w/ 500W going to them. That's approx 106dB with each receiving 1 Watt, and I get around 98dB at the MLP with 1W in. They have around 27 more dB left in them with them at full tilt, for a grand total of 124dB, before EQ robs more headroom, and some LF boost to get flat to 15Hz is added. I can only listen at 10dB below Reference to keep the sound clean......with two THTs! I cannot feed them more power: they are excursion limited unless I highpass them due to the LF boost I apply.

Like many say and have said here, headroom is your friend....I get a laugh out of folks thinking that their 87-88dB 'HiFi' speakers and single 12 or 15" sub are giving them 'Reference Level' with AVR power.....but I distinctly remember a time when my system was just that, and at the time, I thought it was awesome.....but I used to listen at -17 to -20dB when playing 'loud'...

Remember, if you calibrate for reference level with noise and SPL meter before EQ, it is picking up the SPL of the largest peak in your response, and the rest of the freq bands may be limited in SPL.....

JSS

Well of course. It is only logical if people EQ to require more sensitive speakers.
The lowest dip in the FR curve at 1W is the true sensitivity of speaker if it is EQ because you cannot magically get more dB out of speaker just because you EQ. In other words, all other points are EQ'ed DOWN, instead of that point being EQ'ed up.
With that said, a 95dB speaker with a -6dB dip at any point along it's FR curve is actually a 89dB speaker when it is EQ'ed flat.
That is why room treatment is so important also. Anyone can EQ speakers flat, but if a boost is required in any part of the FR curve due to a dip, it is headroom that is lost forever.
What that means, it is much better to EQ speakers with room treatment, than with an actual EQ.
post #57 of 129
Quote:
Originally Posted by yelnatsch517 View Post

Well of course. It is only logical if people EQ to require more sensitive speakers.
The lowest dip in the FR curve at 1W is the true sensitivity of speaker if it is EQ because you cannot magically get more dB out of speaker just because you EQ. In other words, all other points are EQ'ed DOWN, instead of that point being EQ'ed up.
With that said, a 95dB speaker with a -6dB dip at any point along it's FR curve is actually a 89dB speaker when it is EQ'ed flat.
That is why room treatment is so important also. Anyone can EQ speakers flat, but if a boost is required in any part of the FR curve due to a dip, it is headroom that is lost forever.
What that means, it is much better to EQ speakers with room treatment, than with an actual EQ.

Agreed!

But that's not how 'room correction' devices are advertised.....

JSS
post #58 of 129
Or sit 9' away with 98db speaker no eq and still only bother to listen at -15, -10db tops. I'm using less than a watt for most of my watching, but should only need 90 watts to achieve reference.

Of course what I do doesn't mean it's what everyone else does. And that makes what you're saying absolutely correct.
post #59 of 129
I use a 100 watt per channel 5 channel amp at reference with no problems. I also play my subs 9 dBs hot with no problems.
post #60 of 129
Quote:
Originally Posted by MKtheater View Post

I use a 100 watt per channel 5 channel amp at reference with no problems. I also play my subs 9 dBs hot with no problems.

A bit of an unfair comparison to most people's system, given the sensitivity of your speakers wink.gif
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