EMOTIVA Amps - Power Rating Discussion - Page 14 - AVS Forum
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post #391 of 421 Old 03-11-2011, 06:18 AM
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Quote:
Originally Posted by Secret Squirrel View Post

Does anyone have any answers or thoughts to address the OP's original question? This thread has really been derailed by all this talk of posting videos. I really don't think the reason for asking to post a video clip of a system was meant to make a critical analysis of sound quality.

I posted my response in post #351. In summary, any amp that is rated based on clean rms output power over the span of minutes without failure/overheating is rated well. Moreover, this is probably conservative in nature when comparing that test to actual real life performance. However, there will be endless debate on this matter unless a testing standard is developed and followed by all amplifier manufacturers.
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post #392 of 421 Old 03-11-2011, 06:19 AM - Thread Starter
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Originally Posted by Secret Squirrel View Post

Does anyone have any answers or thoughts to address the OP's original question? This thread has really been derailed by all this talk of posting videos. I really don't think the reason for asking to post a video clip of a system was meant to make a critical analysis of sound quality.

Secret - Well stated and factual. Everything has Six Degrees of Freedom, all of which you understand very well with Relativity to solely ones own understanding or in many cases the lack of technical solvency for one w/in the SQ thread. You have an excellent relative understanding of this subject matter, so it seems to me.

As you have previously read on this thread the Emotiva XPA Model numbers (-1, -2, -3) ARE NOT in question -- only the Model XPA-5 of which many have questioned how it can produce it's specifications on a Continuous Basis being rated at 200W RMS/Channel with Five Channels (ACD) driving a Characteristic Impedance of Eight Ohms per Channel.

The General Consensus has been that it can not, if one defines Continuous as Infinite within the Abscissa Time Domain being plotted on the horizontal axis of a two-dimensional Cartesian coordinate system, but it can fulfill the rated specifications for a limited short interval of finite time, exceding it's transformer rating, and with a variac upholding the line AC input to minimize any input line sag per Gene DellaSalla posting on page 3 and 4 of this thread.

To quote Gene "I've tested virtually all of Emotiva's amps and found their power ratings for 1/2CH driven are quite conservative while the ACD are usually a bit off, most likely do to how they test (using a VARIAC to hold line voltage constant) vs how I test it (typical 20A consumer outlet & no line regulation). Their way will always yield higher power #s."
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post #393 of 421 Old 03-11-2011, 06:27 AM - Thread Starter
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Originally Posted by leger433 View Post

I posted my response in post #351. In summary, any amp that is rated based on clean rms output power over the span of minutes without failure/overheating is rated well. Moreover, this is probably conservative in nature when comparing that test to actual real life performance. However, there will be endless debate on this matter unless a testing standard is developed and followed by all amplifier manufacturers.

Leger -- your exactly right and on point, an Endless Debate with no testing standard that All Mfg's. test to, and report on equal footing within their specifications. Please don't try to produce a quantitative spreadsheet comparing different amplifier mfg's. to get a unitized comparison, as you won't be able to, as you know and are aware of.
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post #394 of 421 Old 03-11-2011, 06:27 AM
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Originally Posted by ccotenj View Post

how could listening to a file that he creates and you play back on your speakers in your room possibly tell you anything about how his system sounds?

I'm waiting for the answer too. I'm sure the OP will now flame me for asking him to explain HIS post.

Full Disclosure - I own an XPA-5, but fully accept that it can't defy the laws of physics. It was an inexpensive way to see what impact an amp would have on my system, and I've been happy with it to date, though it certainly doesn't make the list of biggest impacts to SQ.

Does it output a full 200 wpc all channels driven? I'm sure not, but given the price, for me it isn't significant. Specs and adherence to what is published will be far more important when I get the inevitable urge to upgrade to a more expensive amp.

+1 on Chris's knowledge and helpfulness. (Pictures Chris polishing his halo this morning with all of the compliments)
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post #395 of 421 Old 03-11-2011, 07:19 AM
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^^^

you KNOW you want a bryston... especially after i had to wipe the drool marks off of mine when you were over... i owe you a pm, i gotta get over and see/hear that second fathom...

i prefer the black hat...

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post #396 of 421 Old 03-11-2011, 08:20 AM
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Originally Posted by DenPureSound View Post

Knowledge of what is the question, and his postings are only Flames, not constructive at all, just hasty generalization ramblings with no fact(s) to support his implications.

No one is discussing your Degrees there Don.

I am puzzled because I didn't see any "flaming" going on.

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Originally Posted by duckstu View Post

Wow,... this thread went from off-topic to nasty today. (And the off-topic was actually OK as the thread-starter was in on it).

I haven't seen what's on the last page of posts but I thought ccotenj was giving some pretty good advice and after going back and re-reading still wonder what the offending remarks were?
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post #397 of 421 Old 03-11-2011, 10:22 AM
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I weighed in thoroughly on this in post #321

http://www.avsforum.com/avs-vb/showt...1#post20094181

Bottom line is,... music is dynamic, (unlike when you're trying to power a light-bulb).

And with a 5 or 7 channel amp,... the surround channels will never be drawing what the front mains are.

Those 2 factors combined (music is dynamic, big power never required by all speakers at the same time), means that no 5-channel HT amp will ever be asked to out-put full rated power,.. from all channels,.... at the same time. certainly not for minutes or hours at a time.

What you want to be concerned with is it's ability to cleanly output 200 watts into 2-3 channels for a second or two, while the remaining channels are putting out 1/2 (let's say) of their rated output.

If the amp can do that,... it will be as loud and dynamic as five 200W mono-blocks (all else being equal).

But SQ is more important than all of that, or at least it is to me. If the amp really only put out 175 watts per channel,... we're talking about a volume reduction of less than 1db. So you have to ask yourself,..... do you always play the system at reference or 5 db over reference? Right at the point where the amp is clipping? If you don't (and let's hope you don't),... then it's a mute discussion.

Looking at Den's system,..... (BIG amp and very efficient speakers),.. I could see them hitting 125-130 db (rough guess) in the upper frequency range, enough to cause permanent hearing damage. I just can't see how anyone could stand to be in the same room with a row of horn-loaded speakers while they're each being fed an actual 200 Watts RMS.

And in an HT system,... you want all the frequencies to be balanced. So in order to have enough bass to equal that amount of high-end,... I think the OP will need to add a couple more 20A circuits and buy 3 more of those 15" subs.
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post #398 of 421 Old 03-11-2011, 11:01 AM
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Originally Posted by duckstu View Post
... But SQ is more important than all of that, or at least it is to me. If the amp really only put out 175 watts per channel,... we're talking about a volume reduction of less than 1db. So you have to ask yourself,..... do you always play the system at reference or 5 db over reference? Right at the point where the amp is clipping? If you don't (and let's hope you don't),... then it's a mute discussion.
I enjoyed the discussion in the first part of the thread and am glad that the OP started the SQ thread at the same time...Fwiw, Den convinced me that Emotiva amps are pretty "cost effective," if a person needed one and it appears that if he listens to DD 5.1 material at:


Quote:
Originally Posted by DenPureSound View Post
... Around -12 to -10db for 5.1 DD PLII Cinema.
The argument if he actually benifited sonically is legit, but there is no denying that the dude likes his EMOTIVA!!! Fwiw, I wouldn't even experment with level-matching at this point.
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post #399 of 421 Old 03-11-2011, 11:48 AM
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So, here's my summary, imo and fwiwfm:

1. Emotiva amps represent very good value (performance for the money).
2. The transformer wattage rating will not support full power 24/7.
a. Much discussion of whether Emo's specs are "real" or not.
b. (IME) Transformers can sustain wattage above their rating, often significantly above for short-term peaks, and in the long term (many minutes to hours depending upon the overload) at levels perhaps 10% to 50% above rated power will simply get very hot.
3. Chances are that, well within their power ratings, Emo's will sound comparable to most other SS amps. (I realize that I am weasel-wording and that this is an endless debate.)
4. If they meet IHF/FTC testing, like everyone else, they are entitled to their claims depsite the fact that the transformer may not actually support full rated power 24/7 for years...
5. Some people like them, some don't; some people like each other, some don't; the solution is not more amps, but more beer (or whatever).

"After silence, that which best expresses the inexpressible, is music" - Aldous Huxley
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post #400 of 421 Old 03-11-2011, 11:50 AM
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Originally Posted by DonH50 View Post
but more beer (or whatever).
ime, that's always been a reasonable solution...

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post #401 of 421 Old 03-11-2011, 12:29 PM
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And we can make the discussion even more confusing (possibly to the point of being meaningless),... by bringing into the equation a speaker's power ratings and impedance curves.

First power ratings.
Let's say a speaker has a rating of 150 watts. That means it can handle 150 continuously without over-heating the voice-coils (usually referred to as "Thermal Power Handling"). But that doesn't mean a 175 watt amp is too big. That same speaker will be able to handle peaks for a moment of perhaps 250 watts. Basically,... short term it can handle power up to the point where the cones bottom out.

So you want an amp that can drive the speaker to proper volumes,... and have enough in reserve to send out those peaks when needed. When I build car stereos,.. I usually try to size an amp at around 1.5 times the speaker's rated power handling. Better to have a woofer cone go "clunk" once in a great while than clip the amp and smoke the voice-coil. I'd say 90+ percent of woofers are blown because of too little power,... not too much.


Next is impedance curve.
If you look at an impedance graph of a driver or complete speaker,... you'll notice that it is only really a 4 or 8-ohm speaker at one frequency. Here's a graph as an example.

As you can see,... this 3-4 ohm speaker is really only 3-ohm at 15,000 hz. At other frequencies it is as high as 33 ohm.


This means that when your amp is playing music,.... it never really sees 8-ohm loads except during the moments that is is playing that particular frequency that is 8-ohm. The rest of the time it's just loafing.

Here is a graph of a 10" Eminence 6-ohm woofer.
The fine line is the impedance curve,... and the ohms are listed on the right.
As you can see,... the impedance varies from 6-ohms at 220 hz to nearly 100 ohms at 52 hz. If it were crossed over at 150 hz,.. the impedance of this 6-ohm woofer would range from 8-ohm to nearly 100-ohm.



In the end,.... it's a bit of a mess. You won't really know if you're short on power unless you hear the speakers break up at a volume that is too quiet for your needs,... and you won't know if you like an amp's sound until you try it in your own system. That's why Emo's 30 day risk free trials are such a fantastic tool for the customer.
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post #402 of 421 Old 03-11-2011, 12:48 PM
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duckstu,

Way to open up another can of worms just when the debate about amp ratings/actual power output was cooling down! Just kidding. You bring up another excellent point. At the end of the day you are building a complex system with amps/speakers and each and every combination will perform and sound differently. Manufacturers are actually trying to do consumers a favor with simple one line ratings such as:

"100 Watts per channel RMS"
and
"6 ohms nominal"

However, the actual situation is much more complex. I have an easy solution to this whole mess if you can manage to not worry about the details (not likely if you are already reading this). Buy an amp that can drive your speakers based on nominal impedance value (e.g. if you have 4 ohm speakers, make sure the amp can handle it based on manufacturer specs). Moreover, buy as much power as you can afford. You'll never complain about too much power, but too little can be problematic.
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post #403 of 421 Old 03-11-2011, 02:31 PM
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Quote:
Originally Posted by DonH50 View Post

So, here's my summary, imo and fwiwfm:

1. Emotiva amps represent very good value (performance for the money).
2. The transformer wattage rating will not support full power 24/7.
a. Much discussion of whether Emo's specs are "real" or not.
b. (IME) Transformers can sustain wattage above their rating, often significantly above for short-term peaks, and in the long term (many minutes to hours depending upon the overload) at levels perhaps 10% to 50% above rated power will simply get very hot.
3. Chances are that, well within their power ratings, Emo's will sound comparable to most other SS amps. (I realize that I am weasel-wording and that this is an endless debate.)
4. If they meet IHF/FTC testing, like everyone else, they are entitled to their claims depsite the fact that the transformer may not actually support full rated power 24/7 for years...
5. Some people like them, some don't; some people like each other, some don't; the solution is not more amps, but more beer (or whatever).

I don’t think anyone is saying that the amps should be able at run at full power 24/7. For me I want to know if they will run ACD at full power to meet the FTC and DIN requirements. Of course I already know this. The UPA-7 review that has been referenced shows that it won’t. This was at 8 ohm loads. But look at the claims at 4 ohms. The transformers on many of the Emotiva amps would have to be at 200% rated load. I do know enough about transformers to know that is not a good thing for more than a few seconds to maybe a couple of minutes. Once the insulated coating on the winding start to break down it goodbye transformer. At the FTC and DIN times I would suspect that damage could very easily result. On the other hand who is every going to need to do this? For me it is just the fact they make claims that they can’t back up. When you look at other manufacturers and compare their power ratings and transformer sizes they would at least appear to be able to do this.

For that reason I don't think you can make a direct comparision between some of the Emotiva amps (mostly the UPA series) and some of the other companies.

But if we also consider what actually happens when you over drive an amp past its power supply’s limits, the voltage on the rail starts to collapse and the amp breaks into clipping. For any real period of time past a bust the amp will start to clip at a lower power than the amp achieved using a burst test. The transformer will just not produce the long duration powe, at least not without clipping
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post #404 of 421 Old 03-11-2011, 05:15 PM
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Originally Posted by duckstu View Post

That's why Emo's 30 day risk free trials are such a fantastic tool for the customer.

How much does it cost to send one back?
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post #405 of 421 Old 03-11-2011, 05:40 PM
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Quote:
Originally Posted by DonH50 View Post

So, here's my summary, imo and fwiwfm:

1. Emotiva amps represent very good value (performance for the money).
2. The transformer wattage rating will not support full power 24/7.
a. Much discussion of whether Emo's specs are "real" or not.
b. (IME) Transformers can sustain wattage above their rating, often significantly above for short-term peaks, and in the long term (many minutes to hours depending upon the overload) at levels perhaps 10% to 50% above rated power will simply get very hot.
3. Chances are that, well within their power ratings, Emo's will sound comparable to most other SS amps. (I realize that I am weasel-wording and that this is an endless debate.)
4. If they meet IHF/FTC testing, like everyone else, they are entitled to their claims depsite the fact that the transformer may not actually support full rated power 24/7 for years...
5. Some people like them, some don't; some people like each other, some don't; the solution is not more amps, but more beer (or whatever).

Nice summary, but didn't I already say some of this? Just giving you a hard time. You have the "hardware" creds, I am just a software engineer

Your thoughts are always welcome

"But this one goes up to 11"
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post #406 of 421 Old 03-11-2011, 05:48 PM
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Originally Posted by duckstu View Post

And we can make the discussion even more confusing (possibly to the point of being meaningless),... by bringing into the equation a speaker's power ratings and impedance curves.

Based on some recent reading I have been doing, there may be a worst problem than impedance curves.

A speaker could present a tougher than expected load due to the fact that voltage/current are not in phase with each other. According to some stuff I have read, this can result in a quite difficult load even with real world source material for certain speakers.

Hopefully though, most speakers are not so poorly designed.

"But this one goes up to 11"
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post #407 of 421 Old 03-11-2011, 07:28 PM
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You are correct. Technically, impedance has phase, so it could range from purely inductive to purely resistive to purely capacitive. Some amps will have more problems driving different loads depending on the phase angle of the impedance. And, it is not necessarily "poor design" -- the speaker is designed for best sound, and impedance is one of the parameters. "Best sound" and "easy to drive" does not always go together...

"After silence, that which best expresses the inexpressible, is music" - Aldous Huxley
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post #408 of 421 Old 03-11-2011, 07:31 PM
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Originally Posted by Zen Traveler View Post

How much does it cost to send one back?

No idea. Never done it. I'd guess it would be something like $40 or $50. I have an acct at FedEx (takes a minute to set-up). Then I use FedEx Ground Home Delivery (for stuff like this).

I did audition an Emotiva UPA-5 in my home,... but it was one of a pair that a friend of mine had bought. He bought two of them and their pre-pro for his 7.1 setup.

He's using 3 channels from each amp to bi-amp his front mains (Monitor Audio),... and the remaining 2 channels from each amp to power the 4 surrounds. So it didn't cost me anything except one trip to his house. After auditioning it,... I bought a second B&K.
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post #409 of 421 Old 03-11-2011, 09:00 PM
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Quote:
Originally Posted by DonH50 View Post

You are correct. Technically, impedance has phase, so it could range from purely inductive to purely resistive to purely capacitive. Some amps will have more problems driving different loads depending on the phase angle of the impedance. And, it is not necessarily "poor design" -- the speaker is designed for best sound, and impedance is one of the parameters. "Best sound" and "easy to drive" does not always go together...

I would guess the designers of the B&W 802D would agree with you

"But this one goes up to 11"
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post #410 of 421 Old 03-12-2011, 02:34 PM
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I have heard the 801's in several flavors, 803D's, 804's, Nautilus, and a few others, but have actually never heard the 802D's... Back in the 80's B&W did a tour showing off their laser interferometry measurement techniques that were used to refine the 801's. On-topic, a friend of mine drives his 803D's, HTM2D (I think) center, and the matching B&W surrounds with a bunch of Emotiva amps.

"After silence, that which best expresses the inexpressible, is music" - Aldous Huxley
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post #411 of 421 Old 03-12-2011, 03:04 PM
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Originally Posted by MichaelJHuman View Post

Hopefully though, most speakers are not so poorly designed.

Depends on who you ask and who is looking at the speaker design. Its a Reference point kind of thing.

IMO a large majority of speakers are poorly designed, misused, etc.



Quote:
Originally Posted by DonH50 View Post

You are correct. Technically, impedance has phase, so it could range from purely inductive to purely resistive to purely capacitive. Some amps will have more problems driving different loads depending on the phase angle of the impedance. And, it is not necessarily "poor design" -- the speaker is designed for best sound, and impedance is one of the parameters. "Best sound" and "easy to drive" does not always go together...

Honestly there is very limited reasons why impedance curves run wild.

If you spend time reading opinion from expert designers you would realize that most would love to have 16ohm drivers, etc.

The idea of having low dips in the speaker impedance curve is avoidable and silly audiophile stuff if you get into understanding the designs.

There is no correlation to SQ and impedance either. Meaning bad impedance curves and good impedance curve design can sound great because if the amp handles down to 2 ohms, who cares.

Designers who choose to ignore the impedance curves limit their speakers IMO.


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I would guess the designers of the B&W 802D would agree with you

B&W designers do not impress anyone that knows anything about speaker designs Well I will say their marketing and their finish/looks is TOP notch...I think the technicals behind all their speakers are less then steller IMO for some applications (IE Home Theater).

Lets just say B&W engineers could not hold the jock straps of the Harman International engineers

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post #412 of 421 Old 03-12-2011, 03:14 PM
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Quote:
Originally Posted by duckstu View Post

Here is a graph of a 10" Eminence 6-ohm woofer.
The fine line is the impedance curve,... and the ohms are listed on the right.
As you can see,... the impedance varies from 6-ohms at 220 hz to nearly 100 ohms at 52 hz. If it were crossed over at 150 hz,.. the impedance of this 6-ohm woofer would range from 8-ohm to nearly 100-ohm.



In the end,.... it's a bit of a mess. You won't really know if you're short on power unless you hear the speakers break up at a volume that is too quiet for your needs,... and you won't know if you like an amp's sound until you try it in your own system. That's why Emo's 30 day risk free trials are such a fantastic tool for the customer.

Not at all... there is an operating range for that driver. its going to beam above 1800Hz so its XOed probably lower then that also because of the breakup above 1KHz, I would XO below 1KHz and notch filter up higher to eliminate that issue above 2KHz. It also does not go that low.

I would say its a mid range woofer that would be part of a 3-way design. I would Run it from 100Hz to 1000hz, People would port it and run it to 60Hz, the impedance of the driver below 100hz is meaningless because of the port.

So in the operating range its a pretty tame and NORMAL impedance curve. No mess for those who design speakers. You would also realize that with XO creating sometimes Resistors are placed in series with the driver and that acts as a Zoble network with smoothes out the curve more.

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post #413 of 421 Old 03-12-2011, 04:20 PM
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Quote:
Originally Posted by penngray View Post

Depends on who you ask and who is looking at the speaker design. Its a Reference point kind of thing.

IMO a large majority of speakers are poorly designed, misused, etc.





Honestly there is very limited reasons why impedance curves run wild.

If you spend time reading opinion from expert designers you would realize that most would love to have 16ohm drivers, etc.

The idea of having low dips in the speaker impedance curve is avoidable and silly audiophile stuff if you get into understanding the designs.

There is no correlation to SQ and impedance either. Meaning bad impedance curves and good impedance curve design can sound great because if the amp handles down to 2 ohms, who cares.

Designers who choose to ignore the impedance curves limit their speakers IMO.




B&W designers do not impress anyone that knows anything about speaker designs Well I will say their marketing and their finish/looks is TOP notch...I think the technicals behind all their speakers are less then steller IMO for some applications (IE Home Theater).

Lets just say B&W engineers could not hold the jock straps of the Harman International engineers

I have heard some very good B&W speakers.
I say that as an owner of Revel Salons

The Salon 2's say this about impedance:

Quote:


Indicates whether the loudspeaker presents a difficult or easy load on the associated power amplifier. Combined with moderate phase angles, a
minimal impedance specification of 3.7 Ω allows a reasonably designed
power amplifier to drive Revel loudspeakers.

To be safe, I have a Sunfire 7400 (one of the 2 ohm amps)

- Rich

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post #414 of 421 Old 03-12-2011, 05:33 PM
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Quote:
Originally Posted by RichB View Post

I have heard some very good B&W speakers.
I say that as an owner of Revel Salons
- Rich

I've heard a half dozen pairs of B&W speakers (even owned some myself), and about all of them sounded horrid except the 8 series.

My uncle has the origional 801's (non-ported) and powers them with a 500W per channel McIntosh amp, Mac pre-amp, cd player and tuner (in his garage of all places).

I remember years ago when they were in his living room. They sounded very, very good. Possibly the best system I've ever heard in a home.

Yet the 7 and 6 series speakers get easilly humiliated by a $300 pair of Paradigms.

I recently saw a listing for a pair of those origional 801's for like $800. If I had space to store those monsters,... I would have picked them up. They were $5,500 new (1985?) That's like $11,000 today.
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post #415 of 421 Old 03-12-2011, 05:38 PM
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I think my 600 series speakers are fine. Maybe there are better speakers out there, I don't say otherwise.

Watching Kill Bill right now, sounds great. I think the additional Emotiva Ultra-10 sub may have been worth it, but I am still unsure on that one. Still thinking of bass traps though, I just can't figure out where they would go.

"But this one goes up to 11"
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post #416 of 421 Old 03-12-2011, 09:14 PM
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Quote:
Originally Posted by duckstu View Post

I've heard a half dozen pairs of B&W speakers (even owned some myself), and about all of them sounded horrid except the 8 series.

My uncle has the origional 801's (non-ported) and powers them with a 500W per channel McIntosh amp, Mac pre-amp, cd player and tuner (in his garage of all places).

I remember years ago when they were in his living room. They sounded very, very good. Possibly the best system I've ever heard in a home.

Yet the 7 and 6 series speakers get easilly humiliated by a $300 pair of Paradigms.

I recently saw a listing for a pair of those origional 801's for like $800. If I had space to store those monsters,... I would have picked them up. They were $5,500 new (1985?) That's like $11,000 today.

I have heard the 800 series and my only complaint was the midrange which I thought was overly directional (sweet spot required).

It must be difficult to buy speakers these days, there are so many brands and so few places to audition them. Add to that, the variables associated with the equipment. I recently added an Oppo BDP-95 to my system and connected via 5.1 analog and 2 channel balanced connectors to an Onkyo PR-SC5507 preamp.
I was astounded by the difference. Apparently, the Onkyo does not seem to handle PCM very well. The Analog, COAX, and HDMI all sound different. The balance were a revelation.

I find noticably different sount quality with the same equipment in my home when I use different connections. I wonder how you can make judgments in a store?

In the end, the Oppo has convinced me that my Amp is just fine

- Rich

Oppo Beta Group

Oppo BDP-105D | Oppo HA-1 | Oppo PM-1 | Parasound A51 | Revel Salon, Voice, Studio | Velodyne HGS-15
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post #417 of 421 Old 03-18-2011, 10:58 AM
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Quote:
Originally Posted by duckstu View Post

...
Next is impedance curve.
If you look at an impedance graph of a driver or complete speaker,... you'll notice that it is only really a 4 or 8-ohm speaker at one frequency. Here's a graph as an example.

As you can see,... this 3-4 ohm speaker is really only 3-ohm at 15,000 hz. At other frequencies it is as high as 33 ohm.


This means that when your amp is playing music,.... it never really sees 8-ohm loads except during the moments that is is playing that particular frequency that is 8-ohm. The rest of the time it's just loafing.

OK, now if you just add a sensitivity plot...

Quote:
Originally Posted by duckstu View Post

In the end,.... it's a bit of a mess. You won't really know if you're short on power unless you hear the speakers break up at a volume that is too quiet for your needs,... and you won't know if you like an amp's sound until you try it in your own system. That's why Emo's 30 day risk free trials are such a fantastic tool for the customer.

100% What I think is overlooked sometimes is the incredible capability of humans. Many of you will sit in a room, turn the music up, and get a 1000 yard stare while you listen intently at every sound that comes out of your speakers. Your going to hear things and no numbers will change your mind about that.

Signature.
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post #418 of 421 Old 03-18-2011, 12:07 PM
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Originally Posted by dnoyeB View Post
OK, now if you just add a sensitivity plot...


100% What I think is overlooked sometimes is the incredible capability of humans. Many of you will sit in a room, turn the music up, and get a 1000 yard stare while you listen intently at every sound that comes out of your speakers. Your going to hear things and no numbers will change your mind about that.
When i do this I see dead people!
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post #419 of 421 Old 03-19-2011, 02:30 PM - Thread Starter
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Spoke with Audyssey, and they recommended for Dual Subs and a Denon AVR-3311CI, which has dual SW pre-outs even though they are cascaded, to run just one Y-Cable for SW pre-out and then cable over to both subs, then rerun Audyssey.

Sure fixed my Bass Mgmt. problem here, as the subs moved from 12' to 20' per the Denon menu, and now sound excellent, and totally eliminated all the Booming.

Also, Audyssey recommended setting both subs Xover filters to off or zero before running Audyssey. Wow, what a difference this made for Bass Mgmt.
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post #420 of 421 Old 12-23-2013, 01:27 PM
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What I like here is the fact someone is putting either fully rated transformers, overrated transformers, or very close to fully rated toroids. Which thousands upon thousands of amplifiers did not have in the past, or do not have now. Their niche seems to be in the fact many manufacturers have discontinued their separates in favor of mulitchannels, and most of the Big names that produced good amplifiers in the past are now gone, or are not producing a lot of separate amplifiers anymore. While a few big names still make some respectable amplifiers, they are a fortune compared to the old days.

One can even look at the one multichannel amp yamaha makes, the MXA 5000, and you will see a very small looking toroidal, for the 2000.00 they want for the unit. Being a past Yamaha Fan, they have given up the consumer market in my opinion, supplying very little for separates, where they use to be the top selling king. They made a lot of good AV recievers in place of all these seperates, but are loosing the battle here too, or just do not want to make product. In the past I Always seen Yamaha as a good value, Now i find them pricey and skimping out.

I love the XPR series amps by emotiva. All the toroids are well overrated for power output, and they have excellent specifications, which is why the XPR 2 will be replacing all my yamaha mx1000u amplifiers.
I will miss them but there resale value will pay for half my emotiva purchases. One down and two more to purchase.

I would agree with what most said in this thread about the XPA series. The Xpas are not that bad but I like the XPRs so much better. You will never use all the power so it really does not matter if the XPRs come up a few watts short LOL.

A Good amplifier requires a adequate power supply, It does not matter what the amplifier is capable of if the power supply will not provide the power required. Most amplifiers have under rated power supplies. It is up to you to make sure you get the ones that are
least under rated if at all.
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