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Post by kkennally on Aug 28, 2013 18:23:20 GMT -5
I just received my Emotiva XPA-200 and I am now a little confused as to what the actual wattage output is. The Emo website states 150@8ohms and 240@4ohms, however my manual states on page (3) 140@8ohms and 220@4ohms and then again on page (11) (specification page) 120@8ohms and 240@4ohms.......
What the heck???
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novisnick
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Post by novisnick on Aug 28, 2013 19:16:16 GMT -5
I just received my Emotiva XPA-200 and I am now a little confused as to what the actual wattage output is. The Emo website states 150@8ohms and 240@4ohms, however my manual states on page (3) 140@8ohms and 220@4ohms and then again on page (11) (specification page) 120@8ohms and 240@4ohms....... What the heck??? Culd it be s tip oh?  |
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jlafrenz
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Post by jlafrenz on Aug 28, 2013 19:26:22 GMT -5
Either way, you are talking about 10w in the grand scheme of things. It really won't matter either way.
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geebo
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Post by geebo on Aug 28, 2013 19:28:35 GMT -5
I just received my Emotiva XPA-200 and I am now a little confused as to what the actual wattage output is. The Emo website states 150@8ohms and 240@4ohms, however my manual states on page (3) 140@8ohms and 220@4ohms and then again on page (11) (specification page) 120@8ohms and 240@4ohms....... What the heck??? If you look at the test data you'll see both channels at over 149 into 8 ohms and 245 into 4 ohms. The difference, however, is extremely negligible. |
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LCSeminole
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Post by LCSeminole on Aug 28, 2013 19:33:37 GMT -5
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Post by The Mad Norseman on Aug 28, 2013 21:23:03 GMT -5
Page 3 on the 8 Ohm test report seems to indicate that these power tests were all run at only 1KHz, correct? Not from 20Hz - 20KHz??? (Just want to be clear on this....and is that the same for all the other amp bench test results posted too?). |
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Post by audiosanity on Sept 1, 2013 14:40:26 GMT -5
I just received my Emotiva XPA-200 and I am now a little confused as to what the actual wattage output is. The Emo website states 150@8ohms and 240@4ohms, however my manual states on page (3) 140@8ohms and 220@4ohms and then again on page (11) (specification page) 120@8ohms and 240@4ohms....... What the heck??? The online manual is consistent with the online specs. I guess their printed manuals haven't caught up yet with the new specs. At what level of distortion does your manual list the max power output? The online max power spec is for 1%THD. I bet your manual lists power for 0.1%THD, which is (was) the practice for the entire XPA series. The bottom line is that it might look like the specs of the XPA-200 have been "tweaked" to make it look like the half-sized brother of the XPA-2, when in reality it is closer to being its 1/3rd-sized brother. This is simply marketing driven. It is not deceptive, because the industry standard calls for specs at 1%THD, but it is slightly sneaky because the bigger XPAs are rated at a more stringent 0.1%THD level. Actually, I am not even convinced there is any sneakiness involved whatsoever and that this is purely driven by the marketing desire of having round numbers for the power ratings. 135 or 140wpc looks a little weird. And this goes both ways. The gen 2 XPA-2 is rated 300wpc at 0.07%THD. Emotiva could have listed the actual 0.1%THD power rating, which is probably around 310-320wpc (or whatever), but that would have looked a little weird from a marketing point of view. The XPA-2 transformer size is 1,200VA. The XPA-200 has a 360VA transformer. So that right there should give you an idea of how they compare. But the XPA-200 has been designed with a generous capacitance reserve that should allow it to handle big power spikes. Don't worry too much. It looks like a very good amp. |
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Post by garbulky on Sept 1, 2013 14:48:31 GMT -5
Agreed. The XPA-200 is an old UPA-2 slightly upggraded. It is not an XPA-2. I still welcome its addition though.
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Post by solidstate on Sept 1, 2013 16:08:18 GMT -5
Do you know why Emotiva doesn't publish slew rate specs and why they say the XPA series is differential when it's really a single ended design? I'd also like to know why none of the amps are UL/CSA tested and approved. Don't get me wrong I love Emo gear it's just the lack of UL certs really bothers me and I've always wondered why they claim "highly optimized dual differential" when the amp modules are not truly differential even though the amps have balanced/differential inputs. |
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Post by garbulky on Sept 1, 2013 19:38:48 GMT -5
Do you know why Emotiva doesn't publish slew rate specs and why they say the XPA series is differential when it's really a single ended design? I'd also like to know why none of the amps are UL/CSA tested and approved. Don't get me wrong I love Emo gear it's just the lack of UL certs really bothers me and I've always wondered why they claim "highly optimized dual differential" when the amp modules are not truly differential even though the amps have balanced/differential inputs. Their code for real differential or fully balanced is "quad differential". The amps are CE I believe and their opinion is a second certification is redundant. |
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Post by jevans64 on Sept 1, 2013 19:45:32 GMT -5
Underwriter's Laboratory is way over-rated anyway. A shadow of its former self.
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Post by Jim on Sept 1, 2013 20:01:57 GMT -5
]Do you know why Emotiva doesn't publish slew rate specs and why they say the XPA series is differential when it's really a single ended design? I'd also like to know why none of the amps are UL/CSA tested and approved. Don't get me wrong I love Emo gear it's just the lack of UL certs really bothers me and I've always wondered why they claim "highly optimized dual differential" when the amp modules are not truly differential even though the amps have balanced/differential inputs. I would guess they don't publish slew rate because so few manufacturers do - its hard to compare. I'm not even sure Audio Precision gear normally measures it (I'm just guessing though). In my opinion if its high enough - it doesn't matter. I'm in the who cares about UL camp too. Their stamp doesn't carry the significance it used to. |
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Post by KeithL on Sept 2, 2013 3:06:34 GMT -5
1) There was a typo in the manual (actually, the amp hasn't changed, and neither have the test results - we just decided to change the interpretation). I do urge everyone not to obsess over details like this (yeah, we should be consistent). Does your car get 27 mpg or 27.5 mpg? Does it really matter? Really?  2) Everybody uses different "testing and certs" these days. I really wouldn't obsess over those either. Underwriters Lab (UL) is a PRIVATE COMPANY who SELLS testing services. It is NOT a government or official certification of safety - or anything else. This has some value, but doesn't "prove" anything - and they're NOT promising to, for example, buy you a new house if some product they "certify" burns it down after malfunctioning. You can look on our equipment for the logos of the folks we use / comply with. 3) A differential INPUT is NOT the same thing as a "fully differential amplifier". These are both well-defined engineering terms (try Google). A fully differential amplifier MUST have a balanced input (to maintain a fully differential signal path). A fully differential amplifier has two separate amplifiers, one amplifying an in-phase signal; the other an out-of-phase signal; with the two added together to make the output. This results in lower overall distortion because most distortion generated by the amplifiers is equal and opposite, and so cancels out. (You can have an otherwise differential amplifier with a non-differential input; the input is changed to differential at the earliest possible moment; and everything after that is fully differential... like if you use the unbalanced input on an XPA-1.) However, differential INPUTS are popular with all sorts of amplifiers - differential or not - because they have all sorts of engineering benefits. A differential input does not mean that the rest of the amp is differential. In fact, virtually all modern solid state amplifiers, "fully differential" or not, have differential inputs (and even some tube ones do). I believe that includes out VTAC tube amps. "Quad differential" is a little less specific term - and can mean either simply dual dual-differential inputs or dual dual-differential inputs where the inputs are also cross linked. In our case (with the XPA-1) it means a differential amplifier, with each of the two amplifier modules having a dual-differential INPUT... but other folks may use the term differently. If that already sounds confusing, then don't worry about it. Do you know why Emotiva doesn't publish slew rate specs and why they say the XPA series is differential when it's really a single ended design? I'd also like to know why none of the amps are UL/CSA tested and approved. Don't get me wrong I love Emo gear it's just the lack of UL certs really bothers me and I've always wondered why they claim "highly optimized dual differential" when the amp modules are not truly differential even though the amps have balanced/differential inputs. |
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Post by solidstate on Sept 2, 2013 11:39:34 GMT -5
Do you know why Emotiva doesn't publish slew rate specs and why they say the XPA series is differential when it's really a single ended design? I'd also like to know why none of the amps are UL/CSA tested and approved. Don't get me wrong I love Emo gear it's just the lack of UL certs really bothers me and I've always wondered why they claim "highly optimized dual differential" when the amp modules are not truly differential even though the amps have balanced/differential inputs. Their code for real differential or fully balanced is "quad differential". The amps are CE I believe and their opinion is a second certification is redundant. Yeah they are CE and though I'm no engineering expert that's for sure I do not question the safety of the design work after I pulled an amp apart. They even have bleeder resistors but I still discharge the bank when I checked out the design work. I feel neither of my questions were answered BTW. PS I was unaware UL's stamp "doesn't carry the significance it used to" considering after a house wide inspection of my electronics every one has the stamp less my Emo gear. |
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Post by Jim on Sept 2, 2013 11:55:40 GMT -5
Their code for real differential or fully balanced is "quad differential". The amps are CE I believe and their opinion is a second certification is redundant. Yeah they are CE and though I'm no engineering expert that's for sure I do not question the safety of the design work after I pulled an amp apart. They even have bleeder resistors but I still discharge the bank when I checked out the design work. I feel neither of my questions were answered BTW. PS I was unaware UL's stamp "doesn't carry the significance it used to" considering after a house wide inspection of my electronics every one has the stamp less my Emo gear. Why don't you email Emotiva and ask about slew rate? I'm sure Lonnie could respond if you really care. I don't see the UL stamp on all electronics I own - so not sure why I should care that Emotiva gear only carries the CE stamp. If you can explain why the UL stamp should really matter - I'm curious. I don't believe the "if it lacks UL it will burn down your house and your home insurance will be void" argument that people toss out over UL certification typically. |
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DYohn
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Post by DYohn on Sept 2, 2013 12:26:09 GMT -5
UL certification is expensive and rather pointless as all that's really required to maintain UL listing is to send them checks and allow their inspector to make sure you have all your labeling in place. CE or CSA are more valid ways to certify equipment safety IMO as they require actually adhering to certain protocols rather then just assemble your products using materials that bear a UL label. Certification of some sort is required to sell electronics products in many areas, which is why my company spends thousands of dollars each year to maintain UL listings as well as certifying to the other specs (and TUV for those of you in Germany.) But there is no inherent benefit to carrying the UL mark IMHO.
It's a little like THX. 20 years ago THX had real meaning and was a difficult certification to achieve. Today you submit your specs for review, pay the rather large licensing fees and away you go.
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Post by solidstate on Sept 2, 2013 12:35:16 GMT -5
UL certification is expensive and rather pointless as all that's really required to maintain UL listing is to send them checks and allow their inspector to make sure you have all your labeling in place. CE or CSA are more valid ways to certify equipment safety IMO as they require actually adhering to certain protocols rather then just assemble your products using materials that bear a UL label. Certification of some sort is required to sell electronics products in many areas, which is why my company spends thousands of dollars each year to maintain UL listings as well as certifying to the other specs (and TUV for those of you in Germany.) But there is no inherent benefit to carrying the UL mark IMHO. It's a little like THX. 20 years ago THX had real meaning and was a difficult certification to achieve. Today you submit your specs for review, pay the rather large licensing fees and away you go. Thanks for sharing your insider knowledge DYohn. I wasn't aware that UL lacked the credibility it once had. How does the cert/testing process work with CE? I take it you are saying the CE process vets a safer design than UL's rubber stamp or is their vetting process much the same as UL's... |
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Post by solidstate on Sept 2, 2013 12:42:00 GMT -5
UL certification is expensive and rather pointless as all that's really required to maintain UL listing is to send them checks and allow their inspector to make sure you have all your labeling in place. CE or CSA are more valid ways to certify equipment safety IMO as they require actually adhering to certain protocols rather then just assemble your products using materials that bear a UL label. Certification of some sort is required to sell electronics products in many areas, which is why my company spends thousands of dollars each year to maintain UL listings as well as certifying to the other specs (and TUV for those of you in Germany.) But there is no inherent benefit to carrying the UL mark IMHO. It's a little like THX. 20 years ago THX had real meaning and was a difficult certification to achieve. Today you submit your specs for review, pay the rather large licensing fees and away you go. You guys make heaters, thermocouples/RTDs and sensors for semiconductor fabrication right? I bet you sell stuff to the aerospace industry as well. I bet the RoHS thing has been a boom for your surfacemount heaters as the thermal profile/cycles for lead free work is much tighter than traditional fabrication lead solder/flow work. |
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Post by garbulky on Sept 2, 2013 12:48:04 GMT -5
Do you know why Emotiva doesn't publish slew rate specs and why they say the XPA series is differential when it's really a single ended design? I'd also like to know why none of the amps are UL/CSA tested and approved. Don't get me wrong I love Emo gear it's just the lack of UL certs really bothers me and I've always wondered why they claim "highly optimized dual differential" when the amp modules are not truly differential even though the amps have balanced/differential inputs. Their code for real differential or fully balanced is "quad differential". The amps are CE I believe and their opinion is a second certification is redundant. All I got is that's the summary of what emotiva had to say about those questions. There was a slightly lively thread a while ago about certifications fwiw. I have no idea which it is but some guy made an issue about it on other forums and Emotiva told us that they didn't feel the need to have two certifications due to redundancy. |
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Post by DYohn on Sept 2, 2013 12:55:01 GMT -5
You guys make heaters, thermocouples/RTDs and sensors for semiconductor fabrication right? I bet you sell stuff to the aerospace industry as well. That's right, as well as other process equipment used in semi and flat panel (and LED) fabrication. NASA is (or maybe I should say "was" given recent budget cuts) one of our customers, as are Lockheed and Boeing. We manufacture products listed by UL and also that meet SEMI, CE, CSA, TUV, FDA. SAE, ANSi/ASTM and other specs. UL certification is tough to get if you are trying to certify a new material or a new manufacturer. UL materials certs are very meaningful. But when building electronics products you are not generally certifying any new material or process, you are assembling components from other manufacturers. The trick is to use components already listed. That's what we do at our consumer electronics division (we are the OEM for a number of products sold under a variety of labels, and our thermal management group contracts with companies like Samsung, Sony and several Taiwanese and Chinese manufacturers.) In that case all you have to do is pay for the listing and then show the inspection that your bill of materials has not changed. And that's all paperwork... if you get my drift. CE requires certification to a set of safety-related performance standards not just building from a list of already certified components. While they do not send inspectors around regularly like UL does, their system safety requirements are more stringent than UL's. None of these listings have anything to do with actual equipment performance or specifications, they are all about electrical and thermal safety of products, meaning the insulation is sufficient and the surfaces are not too hot to touch, etc. If you want performance certification, look to CEA certification... also dolby and THX, but as I said those certs have lost most of their teeth. (BTW I worked for THX back in 1992 and 93.) |
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