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Post by geebo on Oct 6, 2014 20:47:55 GMT -5
Even if there were markings on the XSP-1 or even if some other analog preamp has markings on the dial (or a digital preamp with a digital display), how do you know the crossover is really what it says it is? Most people don't have the equipment to measure it anyway, right? And as Keith said, the characteristics of the room are going to play havoc with you. Perhaps the biggest benefit of having clearly marked frequencies at each dot on the dial is the peace of mind you get from having clearly marked frequencies at each dot on the dial. Then you can sleep at night and not feel anxiety caused by uncertainty, because the dial says so. I had the XSP and thought the BM was very good. I set both controls the same and adjusted both simultaneously with OmniMic until I got the best response. Knowing what frequencies they were at would have changed absolutely nothing. |
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Post by ansat on Oct 6, 2014 21:31:21 GMT -5
Hello All,
I do not own an XSP and usually on the same page as Keith. But this time I would like to give my thoughts as they differ. Since most subwoofers operate off a dial to set the xover and you are using dials to set the xover on the XSP, my method would be to set the subwoofer to max xover (usually 250). I would use REW and place my measurement mic 6" from the mid-woofer on the speaker. This effectively eliminates most of the room and run a sweep from 30 to 100 with the xover bypassed. I would find the natural roll-off of the mid-woofer. I would set a test tone at that frequency and use a spl meter while running that tone and start adjusting the xover until I am minus 3db. I would set the sub to match the SPL of the mid-woofer and run a test tone at the crossover point and adjust the xover until I am minus 3db again. This is with tools that I own and can work with. If I didn't have the calibrated mic and REW, I would just use a spl meter and get a test tone at the speakers recommended xover setting. If I didn't have the radio shack meter, then I would use my phone. The key is taking your measurements just a few inches from the speaker, not at your listening position.
Tony
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Post by Deleted on Oct 6, 2014 22:31:42 GMT -5
Measuring the electrical frequency as relating to the XO setting seems to me to have little "real world" benefit. It's the tweaking done by your present acoustical environment as a whole that is the most beneficial.
I agree with Keith that the mains are tweaked first, followed by the subs. XO for the subs can't be adequately determined until you know what your mains are doing. I.e, DC 2.0 has shown that my Polk Lsi9's can vary flat from 30hz to 50hz depending on how far into the corner, or how far down the wall of my room they are placed. Where they sound the best overall to me is where I test to see what the low end in them is doing. Once that is determined, I have a good idea where the XO for the subs needs to be. Then it's a matter of experimenting with sub placement.
So again, with the Polks, the XO with the subs could be anywhere from the 30>50z range. Sure, I could set my XO at 80hz, but that is not going to get me the best result ordinarily. Overall from my experience, you set the XO based on your main speakers low end performance, not around a predetermined XO point.
THX came up with 80hz as a standard because it is a pretty good compromise based on the myriad of speaker designs that are out there. It is high enough to relieve much of the bass requirement from mid bass in bookshelf speakers, and it is not so high that typical bass drivers have a response problem due to inductance.....and, it is low enough that the sub is still difficult to localize. Most RC systems seem to have a house curve built around this THX standard of 80hz. Our thinking has been brain washed at 80hz. And, 80hz may be a good place to start, but most often it will not be the best place to end up. It's the speakers, sub(s), and room interaction all together that determine where the best XO point is. You set from that premise, not by trying to force everything to work around 80hz say.
"Perhaps the biggest benefit of having clearly marked frequencies at each dot on the dial is the peace of mind you get from having clearly marked frequencies at each dot on the dial. Then you can sleep at night and not feel anxiety caused by uncertainty, because the dial says so."
Maybe so, but without accurate mark points you need a definitive way to test what is going, or you are simply floundering around trying to make things sound right based on guesswork. Therein lies the challenge for most.
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Post by deltadube on Oct 6, 2014 23:15:39 GMT -5
And giving it even more thought…. considering the XSP-1 is a “stereo preamp”, we should be grateful to have the “variable crossovers” for the sub… and... the mains and… for 2.1 bass management at that!…rather than "one” predetermined by the manufacturer, usually 80Hz. with my xsp 1 gen 1, I went with 2 and 1/2 dots up or 9.30.. to be around 100 hz for the hp and lp filters.. and its sounding awesome... I called into tech support a few times.. I think the dots are linear but its analog so 1 pre amp to the nexts is going to vary a little bit im sure.. I think the most important point which has not been mention in this thread is the XSP 1's ROLL OFF SLOPE at only 12 db / octave it is very subtle .. at 100 x overs you are only -12db at 50hz on the mains and only -12db at 200 hz on the sub seems to be working great in my room for me.. now if you go 8.30 or 80hz appox.. -12db at 40hz and -12db at 160hz think in between those areas you are going to get some really nice over all system results with most floor standers and subs..  but like novis nick im just a novis too lol love the new cables lol  |
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Post by Boomzilla on Oct 6, 2014 23:34:51 GMT -5
Absolutely nothing written subsequently has changed my opinion one iota.
NO EXCUSE!
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Post by deltadube on Oct 6, 2014 23:42:46 GMT -5
OK - Let me say this clearly: The average user has neither the equipment nor the expertise to electrically measure the roll-off of an unmarked electronic crossover. Measuring the in-room response is (grossly) inaccurate. Therefore, I would STRONGLY tell the average user to avoid the XSP-1 like the plague if they're expecting to use it for bass management. Emotiva touts a "feature" that is not readily usable by the average owner. This is fraudulent - period. Without knowing what frequencies the markings correspond to, the user is left to endlessly diddle with the obscure crossover, hoping for a fortuitous result? Emotiva owes their customers better. There is no excuse for a "feature" so poorly engineered as to be virtually unusable. Absolutely no excuse. Boomzilla I think this is total non sense imho, novis Boomer .. lol |
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Post by Chuck Elliot on Oct 6, 2014 23:43:27 GMT -5
I dialed in the crossover section of the XSP-1 Using a BEHRINGER U-CONTROL UCA222 which can be had for < $50.
With it and REW adjust the pot until the signal is -6 dB at the crossover point you desire.
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Post by Boomzilla on Oct 6, 2014 23:50:00 GMT -5
You both miss the point.
Yes, the desired set point CAN be determined with software and additional interface equipment
IF the consumer has the right interface,
IF the consumer has the right software, and, most importantly,
IF the consumer has the knowledge to use those tools.
Most don't. Nor should they have to in order to use a "feature" of the preamp they just bought. If Emotiva tested a random sample of their XSP-1 products and posted the results showing the frequency vs. "reference mark" results WITH a plus and minus variable, THEN the average consumer would have the information that they need. Without such information the XSP-1's "bass management" feature is simply false advertising.
In fact, let's ask the obvious question: Why does Emotiva NOT label their equipment with frequency information (as every other manufacturer does)? They have studiously and repeatedly avoided answering this question. The most likely answers that occur to me are:
1. The taper of the pots have changed (either from model to model or within the same model line) - This would mean that, depending on the serial # of your XSP-1, the "reference marks" mean something different
2. The quality control of the pots is so poor that a marking on one unit would be radically different than the same marking on another (this would also mean that a 10-o-clock frequency for low-pass might NOT match the 10-o-clock frequency for high-pass)
3. Emotiva buys whatever cheap surplus pots are available and even the range of the crossover is radically inaccurate and variable
Are any of these what the consumer wants on a flagship preamplifier? They aren't what I want! Thus my conclusion - NO EXCUSE!
The "bass management" feature of the XSP-1 is ineptly engineered, insufficiently documented, and absolutely unacceptable. Emotiva owes its customers better.
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Post by Chuck Elliot on Oct 7, 2014 0:41:54 GMT -5
No my friend, I think you are missing the point.
What do you think Emotiva should have done?
The only possibilities are: 1. Add a stepped potentiometer systems to control the crossover points; 2. Provide a digitally controlled front end to perform the function.
What would the cost of the XSP-1 be then?
I find the current system adequate although a bit cumbersome. If I ever want more, I’ll add an outboard bass-management system.
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Post by Boomzilla on Oct 7, 2014 0:48:51 GMT -5
The minimum Emotiva owes its customers is a statistically accurate sample of frequency vs. "reference mark" with a plus and minus variable. Given the existing design, this is a reasonable request. It adds little to the cost and provides the customer the (minimum) information needed to use a feature that they paid for.
Don't confuse the issue with expensive alternatives.
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Post by geebo on Oct 7, 2014 7:29:16 GMT -5
Just way too little of an issue to get worked up over. Markings will change nothing except for what I see when looking at the back of the unit which was seldom. It's okay that you want it, but don't try to tell everyone else it's omission is fraudulent. That's a bit extreme.
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Post by rob80b on Oct 7, 2014 7:55:04 GMT -5
As I mentioned elsewhere, when adding a sub and in my case trying to effectively turn a two driver speaker into a 3 way speaker we have to accept to get it properly integrated, much like the original speaker designer it’s not just a matter of choosing a crossover and throwing the drivers into any old box, in this case it's the room and all the pitfalls associated with it. Running test tones and doing measurements until we’re satisfied with the results is going to take time, patience and a lot of work and involves also placement, phase, EQ if available etc, but the final results will be tailored for ones specific listening environment.
As for THX’s 80Hx proposed crossover, we’re dealing with music and not the bombastic bass required for the home theatre experience, tools for getting a half dozen or more speakers to work in a room has become an industry unto its self and there are a quadrillion pages on the net to guide you on your way.
Setting up a sub for “high fidelity music” reproduction IMHO has different requirements and preceded the use of a sub for HT, which in all respects is a recent consumer endeavor.
Subs from thirty years ago designed for music reproduction, literally explode if used to reproduce the loudness required to produce the sub sonic frequencies of modern sound tracks, and that has also created an industry onto itself.
So where does that leave the music lover who also has decided to get into HT, well the USP-1 and now the XSP-1 have for me, by incorporating a 2.1 HT bypass, allowed me to keep my music system intact but of course to do so requires addressing “the crossover”.
This has obviously opened the proverbial “can of worms” as having variable “analogue” crossover adjustments is something most have yet to be confronted with, so yes we’d expect to have clearly marked an delineated reference points.
We are all lazy and when I incorporated the USP-1 I accepted the 11 o’clock position being 80Hz at face value and just inserted it into the chain and forgot about it, even when I started using Velodynes SMS-1 bass management into the chain I still left it at 11 o’clock.
When I received my XSP-1 from Emotiva, the little info I could find was that the dials will now be at 8:30, but was not definitive and doing some cursory visual read outs indicated that it may not be the case. So, it enticed me to get off my derrier and try different settings, and yes, once the unit is in ones rack it is a real PITA to do the adjustments and the reason I started this thread, we all want someone else to do the leg work for us.
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Post by Boomzilla on Oct 7, 2014 8:18:05 GMT -5
Just way too little of an issue to get worked up over. Markings will change nothing except for what I see when looking at the back of the unit which was seldom. It's okay that you want it, but don't try to tell everyone else it's omission is fraudulent. That's a bit extreme. Wrong - The "bass management" feature of the XSP-1 is one of its MAJOR selling points. If the feature is not clearly marked, then it is unusable without a frequency spectrum analyzer and software. In short, the definition of those markings changes EVERYTHING if you want a specific crossover frequency. You, geebo, may consider it a little issue; I don't. And to advertise an unusable feature is the very definition of "fraudulent." So I ask yet again, Lonnie, KiethL? WHY DOES EMOTIVA NOT PROVIDE FREQUENCY INFORMATION? |
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Post by chaosrv on Oct 7, 2014 8:31:32 GMT -5
Didn't we have the same issue with the Gen 1 XSP-1? There was a big dust up over the issue but then it sort of faded away for whatever reason.
I'm not saying this isn't an issue for some, far from it. And yes, more info on the bass management from Emotiva would be ideal.
I'm just confused as to why people are acting as if this is a new & previously unknown phenomenon.
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Post by geebo on Oct 7, 2014 8:35:08 GMT -5
Just way too little of an issue to get worked up over. Markings will change nothing except for what I see when looking at the back of the unit which was seldom. It's okay that you want it, but don't try to tell everyone else it's omission is fraudulent. That's a bit extreme. Wrong - The "bass management" feature of the XSP-1 is one of its MAJOR selling points. If the feature is not clearly marked, then it is unusable without a frequency spectrum analyzer and software. In short, the definition of those markings changes EVERYTHING if you want a specific crossover frequency. You, geebo, may consider it a little issue; I don't. And to advertise an unusable feature is the very definition of "fraudulent." So I ask yet again, Lonnie, KiethL? WHY DOES EMOTIVA NOT PROVIDE FREQUENCY INFORMATION? It's not fraudulent. As much as you want it to be fraudulent, it's not fraudulent. |
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Post by monkumonku on Oct 7, 2014 8:58:43 GMT -5
Just way too little of an issue to get worked up over. Markings will change nothing except for what I see when looking at the back of the unit which was seldom. It's okay that you want it, but don't try to tell everyone else it's omission is fraudulent. That's a bit extreme. Wrong - The "bass management" feature of the XSP-1 is one of its MAJOR selling points. If the feature is not clearly marked, then it is unusable without a frequency spectrum analyzer and software. In short, the definition of those markings changes EVERYTHING if you want a specific crossover frequency. You, geebo, may consider it a little issue; I don't. And to advertise an unusable feature is the very definition of "fraudulent." So I ask yet again, Lonnie, KiethL? WHY DOES EMOTIVA NOT PROVIDE FREQUENCY INFORMATION? I think you're getting a bit excitable.   The XSP-1 Gen 1 had the same situation. The bass management is not "unusable" and certainly not fraudulent. There was no intent on Emo's part to defraud anyone. Haven't you owned at least one of each of the generations? Why didn't you bring up this issue before, if it is such a big deal to the point of accusing Emo of fraud? |
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Post by monkumonku on Oct 7, 2014 9:02:55 GMT -5
No my friend, I think you are missing the point. What do you think Emotiva should have done? The only possibilities are: 1. Add a stepped potentiometer systems to control the crossover points; 2. Provide a digitally controlled front end to perform the function. What would the cost of the XSP-1 be then? I find the current system adequate although a bit cumbersome. If I ever want more, I’ll add an outboard bass-management system. Adding a digitally controlled front end would then have brought out a bunch of howls and complaints about introducing an analog to digital back to analog conversion into the chain. One of the main selling points of the XSP-1 is the purity of the signal chain - all analog. I agree with you, while the bass management is cumbersome it is adequate. No matter what, here's another case of DIYD, DIYD. |
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Post by rob80b on Oct 7, 2014 9:16:57 GMT -5
Wrong - The "bass management" feature of the XSP-1 is one of its MAJOR selling points. ........... With that I would have to concur, if it wasn’t for my search to initially solve the dilemma of incorporating an AVP into my 2.1 stereo set-up I would never have come across the USP-1 and Emotiva. My initial conundrum with the lack of any exact reference on the dials has though greatly subsided, and I have to humbly accept that using a predetermined “specific crossover frequency” may in fact have been a deterrent in dialing in the best settings for my room, speakers and sub. So even if the crossover settings are clearly marked and exactly delineated would still make them redundant and a reference point only and similar to what is already implemented.  I can appreciate the stance of both points of view, but the bottom line is that adding a sub is not plug and play, especially for serious music reproduction. Great strides have been accomplished for automated HT setups, but to keep things solely in the analogue domain for the discriminating audiophile will always require a bit of elbow grease. |
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Post by rob80b on Oct 7, 2014 9:19:20 GMT -5
I'm just confused as to why people are acting as if this is a new & previously unknown phenomenon. It's all my fault...new user.  |
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Post by chaosrv on Oct 7, 2014 9:26:12 GMT -5
I'm just confused as to why people are acting as if this is a new & previously unknown phenomenon. It's all my fault...new user. No fault, my friend. |
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