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Post by aztecax on Feb 11, 2014 14:54:15 GMT -5
Time to separate things out! Would the lucky new owners mind sharing their thoughts again in this, the new dedicated thread?
To start with, I'll say that I had desperately wanted to upgrade to an XSP-1 and and XPA-2 or two XPA 1Ls but I encountered serious demands on my finances come Christmas time. I knew I'd miss the sale price but shrugged and moved on. Then I stopped by the Emotiva site again and saw the Gen II - fantastic. I watched the video and looked through the measurements and test data. Changes have definitely been made, but I'm wondering if offhand anybody can point out clear differences in measurement results between Gen I and Gen II? I no longer have access to the Gen 1 measurements. The XSP Gen I was already shockingly transparent as stated on this board and in Audioholics' thorough review. It's nice to know that Gen II should be cleaner still. I hope Audioholics, Sound & Vision, and/or Stereophile review it. I know Stereophile has a dealer limitation, but Sound & Vision has reviewed Emotiva products numerous times. Thanks!
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Post by leonski on Feb 19, 2014 23:37:13 GMT -5
Measurements are nearly meaningless. And the ONE measurement….or a few, actually, that ARE somewhat important, are NOT included. I'd love to see square wave response (a Picture) and to know the OUTPUT impedance! The last would help in amplifier matching.
I believe time will show the G2 XSP-1 to be more relieable and have a cleaner sound than the G1 version. Surface mount makes most of the difference. The photos make it look 'simplier', though I'm sure that can't be right!
The XPS-1 and a pair of the 1Ls sounds terrific. I'd even like 4x1L and BIAMP my Magnepans. If I could be sure of no impedance mismatch.
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Post by roadrunner on Feb 20, 2014 17:15:54 GMT -5
I think the most significant difference between the XSP-1 and the XSP-1 Gen2 is the fact the Gen 2 can drive power amps with an input impedance as low as 600 Ohms, whereas the XSP-1 is limited by a low impedance match of 10 KOhms or more. This is an indication that the Gen 2 has a more robust power supply and can be used to drive most any power amp. Fortunately, very few power amps have such low input impedance requirements. The Emotiva power amps have input impedance of 100 KOhm, as do most solid state amps. Both generations of the XSP-1 have extremely low distortion levels, far below audible levels, typically below 0.0005%. With a noise floor that low any measured distortion level lower than that is meaningless -- the differences will not be audible, even to golden ear audiophiles. . The total surface mount advantages of the Gen 2 may have some performance impact, but the performance of the first generation XSP-1 is already world-class. See Secrets of Home Theater... for their measured performance, link shown below. hometheaterhifi.com/preamplifiers/preamplifiers-reviews/emotiva-xsp-1-balanced-stereo-preamplifier/page-4-on-the-bench.htmlAll I can say is WOW!!! I have one of the original XSP-1 preamps and love its sound and control. It is without a doubt the best stereo preamp that I have listened to. I highly recommend it to any music lover.
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Post by Gary Cook on Feb 20, 2014 18:03:24 GMT -5
From the XSP-1 Gen 2 Manual Minimum recommended load impedance: 600 ohms Cheers Gary
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Post by leonski on Feb 20, 2014 21:56:06 GMT -5
In keepin with common practice, a load impedance of 600 ohms imples an output impedance of 1/10th that…or 60 ohms. Would that be 30 ohms/leg Balanced? I'm going to have to think about that…….and the possible reasons. How big is that power supply? A 100va transformer? I wonder what the tradeoffs are in the ability to drive such low impedance loads? Also, I've NEVER seen a stereo amp, at least SS, which had such a low input. And I've seen 'em from 20k to 100k. Don't forget the differenced between singled ended (RCA) and Balanced (XLR) also exist with no rule as to which is higher. Though Balanced can ADD UP to higher. You can divide the rating by 2 to get the 'per leg' value.
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Post by roadrunner on Feb 20, 2014 23:44:37 GMT -5
In keepin with common practice, a load impedance of 600 ohms imples an output impedance of 1/10th that…or 60 ohms. Would that be 30 ohms/leg Balanced? I'm going to have to think about that…….and the possible reasons. How big is that power supply? A 100va transformer? I wonder what the tradeoffs are in the ability to drive such low impedance loads? Also, I've NEVER seen a stereo amp, at least SS, which had such a low input. And I've seen 'em from 20k to 100k. Don't forget the differenced between singled ended (RCA) and Balanced (XLR) also exist with no rule as to which is higher. Though Balanced can ADD UP to higher. You can divide the rating by 2 to get the 'per leg' value. To learn what those values are in the XSP-1 Gen2 you will need to contact Ray or Lonnie. They are the two engineers who designed the circuitry of the XSP-1. The only power amps that I know of that have an input impedance of 600 Ohms are a handful of tube amps. I have never heard of a solid state power amp that had an input impedance that low. Most ss amps are in the range of 25 KOhm to 100 KOhm.
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Post by aztecax on Feb 21, 2014 7:53:50 GMT -5
I think the most significant difference between the XSP-1 and the XSP-1 Gen2 is the fact the Gen 2 can drive power amps with an input impedance as low as 600 Ohms, whereas the XSP-1 is limited by a low impedance match of 10 KOhms or more. This is an indication that the Gen 2 has a more robust power supply and can be used to drive most any power amp. Fortunately, very few power amps have such low input impedance requirements. The Emotiva power amps have input impedance of 100 KOhm, as do most solid state amps. Both generations of the XSP-1 have extremely low distortion levels, far below audible levels, typically below 0.0005%. With a noise floor that low any measured distortion level lower than that is meaningless -- the differences will not be audible, even to golden ear audiophiles. . The total surface mount advantages of the Gen 2 may have some performance impact, but the performance of the first generation XSP-1 is already world-class. Right on. Thanks for the answer. The impedance change is substantial and makes it even more versatile. I don't want to have to worry about matching components too much in the future. I agree the measurements were already absurdly low. Can't wait to get one when I have the funds...
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Post by aztecax on Feb 21, 2014 7:59:38 GMT -5
interesting to note that the conclusion to that XSP 1 review praises it with the caveat of:
Well what is there to nitpick now!
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Post by Boomzilla on Feb 21, 2014 8:38:42 GMT -5
I've owned the USP-1 and the XSP-1, both generation ones. I found them admirable mostly for what they didn't do: add coloration to the sound. Garbulky (whose ears are better than mine) thought that the USP-1 added dynamics (he's currently using a passive preamp). I have an XSP-1, generation two on order and will comment when I get it & break it in.
I've owned many preamps including Rotel, Classé, McIntosh, Dynaco (modified & tubed), Marantz, Yamaha, and others. Nothing I've owned for anything near the Emotiva's price was remotely competitive. The McIntoshes that I've owned were every bit as good or better than the Emotivas, but cost more. The tubed Dynaco (the one I'm thinking of here was a Frank Van Alstine mod) had its own charm. For accuracy, though, the McIntosh C41 and the Emotiva XSP-1 are the best two that I've owned (to date).
Don't read too much into preamp specs. They often aren't reliable predictors of sound quality. I had an Onkyo Integra integrated amp once whose specs looked amazing - but the amp sounded so bad I returned it the following day.
I also owned a Pioneer SA-5200 integrated amp rated at 10 wpc with incredibly high distortion. It was one of the sweetest sounding amps I've ever owned!
You MUST listen to electronics to judge their performance. Specs are not reliable predictors of sound quality. At this point, I fully expect KeithL to jump in and say that specs are predictors of accuracy to which I say "maybe." Look again at that Onkyo integrated - on paper, it looked more accurate than just about anything on the market. They'd gotten those excellent specs, though, by designing the circuitry with MASSIVE amounts of global feedback that reduced TIM distortion but at the effect of providing the most "transistory" sound ever heard.
Yes, there is some minimum threshold of specs below which a component MUST sound bad, but it's a LOW threshold.
I plan to listen very, VERY closely to the XSP-1 gen 2 when it arrives. If it isn't a significant sonic improvement over my Oppo BDP-105 feeding the power amp directly, then it will have to go back. I hate to return stuff, but I'll be one of the most critical customers ever for this particular product. I'm expecting great things. Can Emotiva deliver?
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KeithL
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Post by KeithL on Feb 21, 2014 11:36:21 GMT -5
Ooooooowwwww.... I hear my name. Amazingly I'm going to sit the fence this time. Yes, I do still maintain that there is nothing you can't measure these days, and that a FULL set of measurements will define precisely how something sounds. BUT I will also concede that we virtually never get such a full set of measurements - and that, even if we did, we may not understand the results well enough to interpret them correctly. The main flaw of measurements (and it's a biggie) is that they only tell you about what you choose to measure; the next biggest flaw (also rather significant) is that measurements are only as useful as your ability to interpret them (and, often, in the real world, you end up having to trust someone else's interpretation). Transient intermodulation distortion (TIM) is a great example of "the problem" here. Transient distortion basically occurs when you have a design with a lot of feedback and insufficiently high slew rate. Therefore tube amps, which only ever have limited amounts of feedback (for entirely other reasons), never have significant TIM (and horses never get flat tires). TIM also happens to be somewhat difficult to measure directly - and was even more difficult to measure with the technology available twenty five years ago. So, you have something that is hard to measure, that doesn't show up on "the standard tests", and that really wasn't a problem anyway until solid state designs started to appear. So, no big shock that nobody thought to measure it. And, since nobody was measuring it OR specifically designing to avoid it, it did happen quite often. Now, as it turns out, ONCE YOU KNOW WHAT TO LOOK FOR, it's very easy to spot a design that will be likely to exhibit TIM, not too difficult to design things that avoid the design flaws likely to cause it, and actually easy to predict when it is LIKELY to be present from the design parameters and standard measurements. (Only a circuit with a low slew rate AND large amounts of feedback will exhibit TIM; a graph of ordinary THD vs frequency where the THD rises rapidly at the upper audio frequencies is an indicator that TIM may be present.) Since this has been the case, you rarely encounter "professionally designed" products that exhibit audible TIM distortion. As you can see from that situation, however, the value of INCOMPLETE measurements depends on the context (other information you have). If we're looking at a normal solid state amp with a differential input and two or three gain stages, we know that it does have lots of feedback, and we know that its slew rate will also be at least pretty good - but we don't know if the ratio between amount of feedback and slew rate will be good enough to avoid TIM. (But, if we did know both those numbers, and a few others, we COULD calculate if there was sufficient "safety margin" that we didn't have to bother to check.) If our subject is a tube amp, we know that the slew rate is very low by modern standards - but we also know that the amount of feedback is low (and the balance is such that tube designs rarely exhibit TIM distortion). Humans complicate the issue because we each have different preferences, and different tolerances for flaws. You can tell from the measurements that any tube amp will have more noise and higher levels of THD than one of our solid state ones; if you have more complete numbers, you will almost certainly find that those harmonics favor low order ones more, but only you know if you find a little extra second harmonic distortion more annoying than even less fifth harmonic or not, or if you even find that added second harmonic distortion makes music sound "more lively". (Second harmonics are most of what give SET amplifiers their distinctive sound; most people agree that a given percentage of third or fourth harmonics sound worse than the same amount of second harmonics. So, in that case, in order to accurately interpret the measurements, you need to know how much of each harmonic is present, and how you in particular react to each.) So, yes, to take the previous example, measurements are very valuable, and you CAN learn a lot from them, but you have to know how to interpret them - and you may need other context (like what type of design is involved). I would certainly agree that simply comparing a few numbers, without any knowledge of what they really mean, or the context in which they are taken, can be more misleading than useful. (We constantly have this problem where people read this or that measurement on the AP report, then draw entirely false conclusions from it.) One example of this currently in vogue is "global feedback": In a poorly designed circuit, a lot of global feedback can reduce measured static THD numbers, but cause all sorts of other problems. This has lead many people to "know" that "lots of global feedback is bad", and to seek out products designed with "low global feedback". Unfortunately, the reality of the situation is somewhat different. Global feedback, WHEN APPLIED PROPERLY TO A GOOD DESIGN, can reduce both static and dynamic distortion; it is only "bad" when applied IMPROPERLY, or to an otherwise flawed design. There are tradeoffs, and high levels of global feedback are indeed likely to highlight the flaws in a bad design - which is why it may be true that DIYers and amateur engineers are probably better off sticking to "safer" alternatives, but global feedback isn't inherently good or bad. (It's sort of like cooking with salt; the right amount, in the right situation, is good; otherwise it's bad.) The problem is that, just like armchair quarterbacks, there are way too many "armchair engineers" who try to read too much into the measurements and then, when their results don't jive with what they hear, throw up their hands in disgust and declare "the numbers don't matter". If you went to see your doctor about a pain, and he said "I don't trust tests; let's just guess what's wrong and try this drug", I suspect you would be rather unhappy - and probably seek another doctor. Audio specifications are basically the same; they don't always tell the whole story, they may even sometimes lead to wrong conclusions, and you may need an expert to interpret them for you, but by and large they are indeed quite useful. Unfortunately, the alternative (just base your decisions on what other people say "sounds good to them") is even more likely to lead to unexpected and inconsistent results. So, if I had an amplifier that had crummy measured performance, but "sounded sweet" to me, I would surely want to know WHY. (If I know why, then I know what to measure NEXT TIME, or what measurement to look for, which beats the heck out of guessing every time. Unless you have way more money than I do, there are far too many products out there to randomly try every one looking for one you like.) Likewise, if a product that measures well sounds bad to me, then I want to know why - so I can figure out what measurement will tell me which products I can avoid wasting time auditioning. Here's a final example: If ANYONE reading this is even considering buying a ridiculously expensive SET amplifier..... You're a fool if you don't check out a Tripath TA2020 based amp first. The TA2020 is a class-D single-chip audio amplifier. Typical designs deliver about 15 watts per channel (stereo) with some important distortion characteristics that are quite similar to low powered tube amplifiers (monotonic distortion curve). In short, they share some sound characteristics with low-powered tube amps, while NOT sharing several of the flaws - and especially not sharing the absurd prices. Considering the fact that you have dozens of models to choose from on eBay for under $100, you'd really be foolish to spend thousands of dollars on something similar without proving I'm wrong for yourself. (And, if you're really a subjectivist, then what possible reason could you have to not try something his cheap that just might be that good - unless you're silly enough to avoid it because it's too cheap and easy to buy. If you don't think specifications and measurements matter, then what reason could you possibly have for assuming that it ISN'T the best sounding low-powered amplifier in the world?) I've never heard a SET amp that sounded even nearly as good as a TA2020, they share some of the important characteristics that tube lovers supposedly love about tube equipment, and you can have your pick of a dozen models of TA2020-based amp models for under $100 on eBay.) I've owned the USP-1 and the XSP-1, both generation ones. I found them admirable mostly for what they didn't do: add coloration to the sound. Garbulky (whose ears are better than mine) thought that the USP-1 added dynamics (he's currently using a passive preamp). I have an XSP-1, generation two on order and will comment when I get it & break it in. I've owned many preamps including Rotel, Classé, McIntosh, Dynaco (modified & tubed), Marantz, Yamaha, and others. Nothing I've owned for anything near the Emotiva's price was remotely competitive. The McIntoshes that I've owned were every bit as good or better than the Emotivas, but cost more. The tubed Dynaco (the one I'm thinking of here was a Frank Van Alstine mod) had its own charm. For accuracy, though, the McIntosh C41 and the Emotiva XSP-1 are the best two that I've owned (to date). Don't read too much into preamp specs. They often aren't reliable predictors of sound quality. I had an Onkyo Integra integrated amp once whose specs looked amazing - but the amp sounded so bad I returned it the following day. I also owned a Pioneer SA-5200 integrated amp rated at 10 wpc with incredibly high distortion. It was one of the sweetest sounding amps I've ever owned! You MUST listen to electronics to judge their performance. Specs are not reliable predictors of sound quality. At this point, I fully expect KeithL to jump in and say that specs are predictors of accuracy to which I say "maybe." Look again at that Onkyo integrated - on paper, it looked more accurate than just about anything on the market. They'd gotten those excellent specs, though, by designing the circuitry with MASSIVE amounts of global feedback that reduced TIM distortion but at the effect of providing the most "transistory" sound ever heard. Yes, there is some minimum threshold of specs below which a component MUST sound bad, but it's a LOW threshold. I plan to listen very, VERY closely to the XSP-1 gen 2 when it arrives. If it isn't a significant sonic improvement over my Oppo BDP-105 feeding the power amp directly, then it will have to go back. I hate to return stuff, but I'll be one of the most critical customers ever for this particular product. I'm expecting great things. Can Emotiva deliver?
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Post by RightinLA on Feb 21, 2014 11:45:39 GMT -5
These are cool little amps. The Lepai LP-808 Stereo amplifer built with LA4636 Sanyo Chip is another amp and is of better quality than many of the TA2020 Lepai amps. (I have a small collection of these various amps, what else is new) I use two of them in my office that I purchased along with a power supply for less than $15 each. Since the sound is near field and volume is low, they are just an excellent choice for the purpose.
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Post by Boomzilla on Feb 21, 2014 15:59:07 GMT -5
Hi KeithL - Agreed point for point. Yes, specifications are valuable and necessary for design engineers (of which I'm not). My assumption is that the specifications published for any given amplifier or preamp are those that the maker assumes will cast their product in the most favorable light. Are the specifications useful? Probably not, because the consumer (if they even know what the specifications mean) doesn't know how the measurements were taken. Full power? Half power? Wherever on the power band the specification came out the best? At what frequency? Often, no way to know...
Do I care what someone else thought of the sound? Maybe a little, but not very much. Why? Because I have no way to know what aspects of audio are important to the other listener. As one Lounger said recently (and very profoundly): "Reviews are written for the reviewer."
So how do I judge the quality of an electronic component? By listening. I know what live music should sound like (yes, even in my own living room, since my daughter has been a musician for many, many years and we were the only parents consistently willing to provide a practice venue for various string quartets). If the device under test doesn't make known recordings sound like live music to me, then I don't want that component.
Has my hearing changed over time? Yes. Has the sound of my room changed since adding absorbers, etc.? Yes. Do I still know what live music sounds like to me? Yes.
Do I still care about specifications in spite of all this? Yes. Why? Because I'm stubborn enough to think (probably mistakenly) that I can at least infer some evaluation of sound quality based on specs. Regardless of that, if the component doesn't sound right, regardless of specs, then I don't want it. Listening trumps specs every time.
Am I a curmudgeon? Yes!
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Post by dogsled on Jan 9, 2015 11:36:43 GMT -5
Have the original XSP-1, and it has been a good performer, except for the capacitor exploding...Emotiva did fix it (finally) but took a while. Measurements are only meaningless when they cannot be correlated to perceived performance. Distortion in general is quite an interesting spec, and research indicates the human hearing mechanism is much more complicated than once thought. I would be concerned that the 0.0005% distortion spec is due to high amounts of loop feedback, and the distortions thus heard are of a "different" nature. Remember the DB Systems preamp? It also had vanishing low distortion, and many audiophiles really didn't like the sound. It is possible many of us like 'some' distortion due to a number of factors including source material. I have many recordings I like that have sonic issues, and these issues are exacerbated by some audio equipment. There is also good indication that higher order harmonic and IM distortion products are perceived as "nasty", where 2nd order & 3rd order mixtures can be perceived as 'sweet' and 'dynamic". Hiraga & Nelson Pass have some interesting comments on these distortion issues... Thus many measurements are quite useful, and can tell a lot about what to expect from a piece of gear, especially how it may interact. Many of the ultra-simple amplifiers ( First Watt, SET, etc) require a very low impedance drive, and the new XSP-1 should provide that. My original XSP-1 will suffer from low & high freq rolloff, which may be slight, but is still there, when driving a First Watt F6. Also, when comparing my XSP-1 in circuit, with a Mytek DAC driving a VT-130 amplifier directly, there is some harshness added by the preamp. It is possible the output impedance of the XSP-1 is not sufficiently low enough, but the VT-130 has a balanced FET front end, so I suspect something else. I do enjoy the flexibility, and features of the XSP-1, but may have to re-think my application. equipment: Audio research VT-130, Denon 700C, Mytec DSD 192, SOTA Sapphire, JBL LSR6332, XSP-1 Cheers.
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Post by garbulky on Jan 9, 2015 13:03:46 GMT -5
dogsled: I have some questions regarding your intepretation. You see a low distortion spec and are concerned? It's hard to say if it is acheieved by a loop feedback or just kickbutt electronics would be my counter. I am interested in what you said about the impedance: the XSP-1 gen 2 has slightly lower output impedance than the gen 2. But your DAC is already pretty high end. We experienced different results when trying different DAC's. For example for some wierd reason the dc-1 sounded recessed and somewhat bloated on the gen 2 unit (granted - I tried this in a different room than mine) so I do wonder if something to do with impedance is coming into play. The XSP-1 reccomends a minimum input impedance of 600 ohms which I suspect your mytek is outputting a lot lower than that. The oppo 105 on the other hand ran very nicely with the XSP-1 and so for some reason did the XDA-2.
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Post by emotifan on Jan 9, 2015 13:38:05 GMT -5
I've owned the USP-1 and the XSP-1, both generation ones. I found them admirable mostly for what they didn't do: add coloration to the sound. Garbulky (whose ears are better than mine) thought that the USP-1 added dynamics (he's currently using a passive preamp). I have an XSP-1, generation two on order and will comment when I get it & break it in. I've owned many preamps including Rotel, Classé, McIntosh, Dynaco (modified & tubed), Marantz, Yamaha, and others. Nothing I've owned for anything near the Emotiva's price was remotely competitive. The McIntoshes that I've owned were every bit as good or better than the Emotivas, but cost more. The tubed Dynaco (the one I'm thinking of here was a Frank Van Alstine mod) had its own charm. For accuracy, though, the McIntosh C41 and the Emotiva XSP-1 are the best two that I've owned (to date). Don't read too much into preamp specs. They often aren't reliable predictors of sound quality. I had an Onkyo Integra integrated amp once whose specs looked amazing - but the amp sounded so bad I returned it the following day. I also owned a Pioneer SA-5200 integrated amp rated at 10 wpc with incredibly high distortion. It was one of the sweetest sounding amps I've ever owned! You MUST listen to electronics to judge their performance. Specs are not reliable predictors of sound quality. At this point, I fully expect KeithL to jump in and say that specs are predictors of accuracy to which I say "maybe." Look again at that Onkyo integrated - on paper, it looked more accurate than just about anything on the market. They'd gotten those excellent specs, though, by designing the circuitry with MASSIVE amounts of global feedback that reduced TIM distortion but at the effect of providing the most "transistory" sound ever heard. Yes, there is some minimum threshold of specs below which a component MUST sound bad, but it's a LOW threshold. I plan to listen very, VERY closely to the XSP-1 gen 2 when it arrives. If it isn't a significant sonic improvement over my Oppo BDP-105 feeding the power amp directly, then it will have to go back. I hate to return stuff, but I'll be one of the most critical customers ever for this particular product. I'm expecting great things. Can Emotiva deliver? Since I'm looking at ordering an XSP-1 Gen2 within the next month I'll be looking forward to that review.
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Post by stlaudiofan1 on Jan 9, 2015 13:50:24 GMT -5
Measurements are nearly meaningless. And the ONE measurement….or a few, actually, that ARE somewhat important, are NOT included. I'd love to see square wave response (a Picture) and to know the OUTPUT impedance! The last would help in amplifier matching. I believe time will show the G2 XSP-1 to be more relieable and have a cleaner sound than the G1 version. Surface mount makes most of the difference. The photos make it look 'simplier', though I'm sure that can't be right! The XPS-1 and a pair of the 1Ls sounds terrific. I'd even like 4x1L and BIAMP my Magnepans. If I could be sure of no impedance mismatch. I recently (3 weeks ago) revamped my system. I purchased the ERC-3, XSP-1 Gen 2 and 2x1L. I'm running balanced all the way through with Mogami Studio Gold cables. I also have Magnepan 1.6QRs and a sub. The sound is fantastic. So...I went into "gimme some more of that mode". After talking it over with Emotiva, I decided to order 2 more 1Ls and bi-amp my Magnepans. It's a bit of a rabbit hole because I also needed 4 more balanced cables and the Emotiva 1x2BAL splitter. I wanted to keep with the Mogami cabling. Then....I figured out that I didn't have enough outlets, so I ordered 2 of the Emotiva filtered 2 outlet power strips for each channel of amplifiers. Just ordered the second wave of stuff yesterday, so it is on its way. I will let you know how it sounds.
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Post by stlaudiofan1 on Jan 9, 2015 15:26:56 GMT -5
Sorry. Didn't realize this post was from 2014.
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Post by leonski on Jan 9, 2015 15:40:10 GMT -5
At some point, turn-ON surge may become an issue. A dedicated outlet MAY be indicated. Now, I'm doing a similar amp scheme with my panels. A Parasound A23 of 200x2@4 per speaker, which is a little less than I had with the 'd' amp these replace. Each amp has an input and output to another channel. so, I run ONE single ended to the amp, and a SHORT loop-over to the other channel. But the GOAL? FORGET the Speaker Level Crossover and go to a Line Level Crossover BETWEEN amp and PREamp. You will gain as much as 3db of apparent amp power since right now, EACH amp is dealing with the Full Range signal and the speaker crossover is sorting it out. Limiting each amp to the frequency range of the driver it is DIRECTLY connected to is good. And besides, have you Priced the PREMIUM caps and big AIRCORE inductor needed for THAT modification? Not to mention the fact that it would NOT fit where the current crossover is, with the iron core inductor and physically smaller caps. Just my opinion, but while it seems Maggies DO respond well to Your Plan, the line level crossover is a whole New Deal You just MIGHT want to wander over to Audio Asylum and get with the Planar Asylum folks and read, than ask a few questions. They have a huge knowledge base and a bunch of folks willing to help with this specific issue. And, from our FWIW department? I'd take the drivers out of that ratty MDF frame and get some NICE OAK, MAPLE, CHERRY or perhap MAHOGONY, for a reframe / stand. Sound improves when you get RID of that MDF which is nasty stuff.
You ALSO need to keep the INPUT impedance of the amps in relation to the OUTPUT impedance of the preamp in mind. The spec says 50k input impedance. I'd make SURE that is for balanced, too, which would work out to 25k per LEG. (it adds). If the preamp is say, 1k or LESS per leg, you're golden. Rule of thumb is what? 5:1 ratio? But it varies by frequency, so may have some weird effects at the highest or lowest frequencies.
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Post by Boomzilla on Jan 9, 2015 16:44:56 GMT -5
Since I'm looking at ordering an XSP-1 Gen2 within the next month I'll be looking forward to that review. Hi emotifan - I DID keep my XSP-1 Gen II. Initially, I wasn't too fond of it (I thought it slightly rolled off the high frequencies), but after a week or two, either the preamp "burned in" or my ears adjusted. What the XSP-1 brings to the table that my Oppo driving the amps directly didn't is midrange solidity and increased dynamics. My friend, garbulky, thinks that the output amps in the Oppo aren't robust enough to adequately control the power amplifiers (Emotiva XPA-1Ls among others) and that the XSP-1's output amps are sufficiently powerful. Whether he's right or not, I do hear a stronger, clearer midrange through the XSP-1 than with the Oppo by itself. Additionally, the dynamics seem to improve (but slightly) with the preamp in the circuit. My sole complaint about the XSP-1 is the lack of specificity on the bass management. You get two pots to adjust the low-pass and high-pass with no indication (or instruction) on what frequencies are represented by what markings. You'll have to fiddle around with the pots until you get your bass crossover working "by ear." If you're willing to fiddle with the crossover, then I recommend the preamp without reservation. If you want more indication, then buy the Rotel preamp instead. I ended up with both my pots set at about 12:00 and although I don't really know where the crossover point is, since I can't hear the transition, it's OK. By the bye, I run fully balanced from the Oppo to the XSP-1 and from the XSP-1 to the power amp(s). That said, I hear no difference from using unbalanced RCA connectors. YMMV... Happy Shopping - Boomzilla
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Post by emotifan on Jan 9, 2015 17:02:48 GMT -5
Low pass management is the same on the USP-1. I just assumed each hash mark equals 20 hz up or down. That's what the division works out to between the upper and lower frequencies.
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