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Post by pallpoul on Jun 12, 2018 23:14:17 GMT -5
Thanks for the update. Some future enthusiasts will surly cry for not having a set. 😢 I am already!! Get a pair Gar ! |
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Post by novisnick on Jun 12, 2018 23:25:17 GMT -5
Do you mean, “Get another Pair” ? |
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Post by pallpoul on Jun 13, 2018 0:02:04 GMT -5
Do you mean, “Get another Pair” ? More is better,..! |
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Post by donh50 on Jun 15, 2018 9:31:08 GMT -5
There are a myriad of line-level crossovers around... To toss out a few, the inexpensive ('ish, ~$200 USD) dbx223 is one of my "go-to" active crossovers; works for subs too, balanced IO, purely analog, etc. The miniDSP units are cheap and powerful for those who like to tinker. Higher up the chain are Marchand passive and active crossovers, then Bryston makes a very nice albeit expensive crossover. Have they said what is replacing the XPA-1? Is there a Gen3 in the works? Years ago I talked with Emotiva about using the XPA-1 on speakers that dipped to ~2 ohms or a little below (nominal 4-6 ohms) and they were hesitant to recommend driving that low. I bought an XPA-2, saving some money and plenty of power for me, but curious if people are using XPA-1s with relatively low-Z speakers? ESLs, some conventional speakers, and some ribbon tweeters (e.g. Magnepan) dip to about 3 ohms or below at various frequencies. I don't know if it is Still Available, but Pass Labs made a crossover which was massively flexible. And $$$$ I'd personally start my 'tinkering' with the MiniDSP by duplicating the speakers crossover as closely as possible. MiniDSP can also (in some products) support FIR Filters. These have NO phase shift thru the passband. This makes phase connections of speakers somewhat easier. I'd really love to try that on my panels. Math intensive and what looks to be a steep learning curve. For the Marchand? You need to purchase 'modules' for the desired frequency and hi or lo pass. If you want to experiment, that can start to add up. In addition to the low 'Z' of stats, at higher frequencies they start looking more like a capacitor or inductor to the partnering amp. Some amps simply do not like that and can go into self-oscillation. Not many, but it does happen. I heard it once when auditioning my MG-1 panels. The owners hooked up an amp to some 'Stats and it just went 'Zorch!' Maggies have the advantage of not being a wildly reactive load. And that Ribbon Tweeter is considered one of the finest available. I suspect the XPA-1 or -2 would drive 3 ohms all day long, since it is restricted in frequency, so not much power overall, and is of low reactance. A win-win. I have a buddy with a pair of large EMO monoblocks on the 'lows' of his MG20s. And it sounds FABULOUS. Sure, you can get passive attenuators which simply plug in-line. And fairly priced. But why ADD more stuff when all the gain functions you could ever Imagine were included in the MiniDSP? EACH input channel had a 5 band parametric EQ. Each OutPut has Another 5 bands of Parametric EQ. You can design and implement 'shelves', 'notches' and 'slopes' to your hearts content. If you even THINK you are leaning in that direction, the calibrated mic and REW would, IMO, not be optional, but ReQuired. Forgot about the Pass, thanks. I have not looked for a crossover in years since I quit bi-amping my mains and shifted to the XMC-1 with its more flexible crossover settings (my previous Pioneer used a global crossover, not a good fit to my system, so I threw the dbx into the system). I thought Marchand made some active crossovers that allowed continuous adjustment of the frequencies? May have mis-remembered, or they may have dropped them. Not cheap either way. Yah, Maggies are a fairly benign load except (a) a bit low and (b) they are not very sensitive. I first used an ARC tube crossover with mine ca. 30 years ago but switched to a simple passive crossover I built into my (SP3a1) preamp when I bi-amped my MG-IIIa's long ago. These days I don't think it's worth the hassle and am running a single amp. I recently switched to Revel Salon2's, which sound nice but are a more difficult load than the Maggies (understatement). The main reason I skipped the pair of XPA-1's was cost, not concern about the load, FWIW. Not like I have Apogee Grands... I am very tempted to pick up a pair whilst on closeout, but don't really need them and have other expenses right now. Sure a year from now I'll be wishing I had... In-line passive attenuators will get you in the ballpark if your speaker/amp combination exceeds the trim range of your processor or AVR. Fine-tuning for precise level matching takes a little more work but these days of DSP is rarely needed. A miniDSP seems like a nice little unit, and I keep meaning to try one, but Work and Life keeps me busy and I do not have a real need. The DSP aspect doesn;t scare me since I did have several grad classes in that area years ago (but am an analog designer so would have to brush up). I had a nice, and expensive (>$10k), measurement rig that has been superceded by REW and a calibrated UMIK-1 for almost everything. The REW rig is easier to use, has more features, and the calibrated mic's response almost overlies my measurement mic's response (Earthworks M30; the UMIK-1 does not have the dynamic range or as extended frequency response, but from ~10 Hz to 20+ kHz provides almost identical response when using the CSL cal file). In these days where most things seem to cost a fortune it is amazing what $100 or so can get you. |
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Post by mrranting on Jun 15, 2018 9:31:25 GMT -5
I'm missing something. Aren't the RF7's around 100 db sensitivity? And the big EMO mono amps are maybe 500 or 600 watts? I never drive my emo amps anywhere close to its max. Most of the time one owuld be listening at about a watt or maybe two. So I guess I'm really talking about how I like its sound at that power. Most of my listening is below 80 db around low 70's. Rf7ii do have 101db efficiency. However, they have a nasty impedance drop that goes down to 3ohms around the 70hz mark. The more power you feed the less that drop effects clarity. They are very thirsty for power. I'm sure you could do get the job done with other options but who doesn't want 300w of headroom to play with. |
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Post by donh50 on Jun 15, 2018 9:44:10 GMT -5
1)
For those who DON'T like to tinker too much, these guys make a line-level passive subwoofer crossover with selectable crossover frequencies for about $50. 2) The replacement for the XPA-1 Gen3 is the XPA-DR1 Gen3. 3) Speakers with an extremely low impedance are always a dicey issue. A speaker that exhibits a 2 Ohm impedance across a wide range of frequencies is going to cause most amplifiers to run very hot - possibly to the point of overheating. (Any Class A/B amplifier operates less efficiently at impedances that are far below those it is designed for.... ) That's why we don't recommend most of our amps for use with low impedance subwoofers.
However, this issue is less of a factor for speakers whose impedance is only very low at very high frequencies, where there is little musical energy being delivered. Another issue with electrostatic speakers is that, not only is their impedance very low at high frequencies, but they pose an almost purely capacitive load.
Because of THIS, they can pose stability issues for some amplifiers. Most of our amps would be subject to the heating issue, but are quite stable, so they would probably not have stability issues. However, driving a 2 Ohm load with an amp not specifically designed for a load that low is always going to carry some risk of shortening its life.
Thanks Keith. The actual ESL panel is capacitive, but the phase angle the amp sees can be a little different after passing through the HV transformer (if one is present). Either way, it can be a challenging load, but I agree power is usually low as well so most amps don;t have problems (as long as they are stable -- see below). IME conventional speakers with their wildly varying impedance offer more of a challenge in terms of frequency response. IME folk (including me) end up getting more powerful amps than they really need because they have lower output impedance and so vary less with the load. The long-ago amp/cable story was at a Chicago CES when a pair of Cobra Cables (interwoven braided speaker cables, that was when Litz wires were the rage) were plumbed to a pair of Infinity class-D amplifiers (very early in the class D world) and (I think, someone else probably remembers, was a long time ago even though I was there) Servo-Statik speakers. The extra cable capacitance caused the amps to go unstable. They made a "zip" sound from low to high and died on the spot. We thought the Infinity guy was going to take his wire cutters and chop the cables up. The classic "low but resistive" speaker was the original Apogee full-range ribbons. Sub 1-ohm. Any amp that could not arc weld need not apply.  |
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Post by mrranting on Jun 15, 2018 9:50:57 GMT -5
Hey everyone, I wanted to make everyone aware that we are closing out the last batch of our XPA-1 Gen2 Monoblock class A/AB amps. They are 20% off until they sell out. I wanted to make everyone here aware first before the email blast goes out this afternoon. These last ones should go very quickly and when they are gone they are gone for good. emotiva.com/products/xpa-1-gen2We are down to single digits of available XPA-1 G2s, so if you still considering it, this is your last chance! Hey any word on when they will ship. Got mine ordered a few weeks ago, the wait is killing me. Thanks in advance. |
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Post by donh50 on Jun 15, 2018 9:51:25 GMT -5
Speaker sensitivity is usually measured at 1 kHz. Hybrids with horns on top and conventional drivers below can thus spec a very high sensitivity yet the real-world sensitivity is much lower given the LF conventional drivers where the most power is needed. Take with grain (block?) of salt.
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Post by craigl59 on Jun 15, 2018 11:26:20 GMT -5
mrranting:
Sarah in customer service told me 2 days ago that they had been shipped from China and were projected to be shipped to customers in mid to late July. If not, will have to cancel my order as my summer needs only extend to July for this amp.
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Post by leonski on Jun 15, 2018 12:43:30 GMT -5
Good stuff in the last posts.
Yep, the Apogee SCintilla was a 1 ohm load and had a very SHORT list of amps which were successful with it.
That 'zip' noise? I heard the same thing with the same result when I bought my original MG-1 panels. Mid 80s? no later.
Guys were experimenting with stuff (a real pair of DIY brothers) when something got out of hand. ZORCH!
I wonder about speaker sensitivity being measured at a single frequency. If that were true, then sensitivity is meaningless with the huge output variation over the audio band.
As sensitivity varied?
And don't forget that in the heyday of 'Big Box' speakers.....like Voice Of The Theater and Bozak and Klipsch types.....the woofer DID have very high sensitivity. And was a reasonable match
for the mid / high horns.
And as I understand it, the 50:50 power point for normal (whatever that is) music is about 350hz. The main takeaway is for biamp guys who must apportion power when doing the setup....
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Post by pknaz on Jun 15, 2018 12:50:18 GMT -5
Good stuff in the last posts. Yep, the Apogee SCintilla was a 1 ohm load and had a very SHORT list of amps which were successful with it. That 'zip' noise? I heard the same thing with the same result when I bought my original MG-1 panels. Mid 80s? no later. Guys were experimenting with stuff (a real pair of DIY brothers) when something got out of hand. ZORCH! I wonder about speaker sensitivity being measured at a single frequency. If that were true, then sensitivity is meaningless with the huge output variation over the audio band. As sensitivity varied? And don't forget that in the heyday of 'Big Box' speakers.....like Voice Of The Theater and Bozak and Klipsch types.....the woofer DID have very high sensitivity. And was a reasonable match for the mid / high horns. And as I understand it, the 50:50 power point for normal (whatever that is) music is about 350hz. The main takeaway is for biamp guys who must apportion power when doing the setup.... That's where crossovers come into play, they're essentially a level match and EQ for the "system" (Speaker system). Sensitivity is only meaningful if it is measured from 20-20khz or if measured at 1khz (or other random frequency) and frequency response is also provided. If you know the frequency response and the sensitivity at a given frequency, you can calculate the required power at any other frequency for a given SPL at said frequency. |
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Post by teaman on Jun 15, 2018 13:41:02 GMT -5
mrranting: Sarah in customer service told me 2 days ago that they had been shipped from China and were projected to be shipped to customers in mid to late July. If not, will have to cancel my order as my summer needs only extend to July for this amp. I'm hoping this isn't accurate for Ryan's sake. He was told two weeks at the time of purchase and now it is being dragged back another month? Why can nobody seem to know when the hell the product is going to be ready to ship? Since I referred Ryan to buy his pair of XPA-1 I take it personally if someone has been stringing him a line of crap in order to get him to purchase. There were several pair of lightly used XPA-1 Gen 2 with remaining warranty on the market when he was deciding whether or not to buy new. Someone from Emotiva, would you please give him a straight answer. Anyone? Jessica, Jenna, Dan, Cathy?.... |
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Post by pedrocols on Jun 15, 2018 14:57:33 GMT -5
mrranting: Sarah in customer service told me 2 days ago that they had been shipped from China and were projected to be shipped to customers in mid to late July. If not, will have to cancel my order as my summer needs only extend to July for this amp. I'm hoping this isn't accurate for Ryan's sake. He was told two weeks at the time of purchase and now it is being dragged back another month? Why can nobody seem to know when the hell the product is going to be ready to ship? Since I referred Ryan to buy his pair of XPA-1 I take it personally if someone has been stringing him a line of crap in order to get him to purchase. There were several pair of lightly used XPA-1 Gen 2 with remaining warranty on the market when he was deciding whether or not to buy new. Someone from Emotiva, would you please give him a straight answer. Anyone? Jessica, Jenna, Dan, Cathy?.... That would be too easy and potentially from their point of view bad for business...🤔 |
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Post by craigl59 on Jun 15, 2018 17:51:25 GMT -5
mrranting: Sarah in customer service told me 2 days ago that they had been shipped from China and were projected to be shipped to customers in mid to late July. If not, will have to cancel my order as my summer needs only extend to July for this amp. I'm hoping this isn't accurate for Ryan's sake. He was told two weeks at the time of purchase and now it is being dragged back another month? Why can nobody seem to know when the hell the product is going to be ready to ship? Since I referred Ryan to buy his pair of XPA-1 I take it personally if someone has been stringing him a line of crap in order to get him to purchase. There were several pair of lightly used XPA-1 Gen 2 with remaining warranty on the market when he was deciding whether or not to buy new. Someone from Emotiva, would you please give him a straight answer. Anyone? Jessica, Jenna, Dan, Cathy?.... |
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Post by emofrmcgy on Jun 15, 2018 17:57:22 GMT -5
mrranting: Sarah in customer service told me 2 days ago that they had been shipped from China and were projected to be shipped to customers in mid to late July. If not, will have to cancel my order as my summer needs only extend to July for this amp. I'm hoping this isn't accurate for Ryan's sake. He was told two weeks at the time of purchase and now it is being dragged back another month? Why can nobody seem to know when the hell the product is going to be ready to ship? Since I referred Ryan to buy his pair of XPA-1 I take it personally if someone has been stringing him a line of crap in order to get him to purchase. There were several pair of lightly used XPA-1 Gen 2 with remaining warranty on the market when he was deciding whether or not to buy new. Someone from Emotiva, would you please give him a straight answer. Anyone? Jessica, Jenna, Dan, Cathy?.... In the first 4 posts of this thread they say 7weeks before they’ll begin shipping. Mid to late July seems to be when that target would fall. |
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arjna
Seeker Of Truth
Posts: 9
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Post by arjna on Jun 15, 2018 18:14:44 GMT -5
Sold out.
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Post by craigl59 on Jun 15, 2018 18:39:38 GMT -5
arjna:
No surprise here. The unit has been a standard for some time and I, like others above, cannot understand why Emotive is abandoning the class A world. There is no real competition at this price point.
Tant pis!
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Post by DavidR on Jun 15, 2018 21:16:49 GMT -5
arjna: No surprise here. The unit has been a standard for some time and I, like others above, cannot understand why Emotive is abandoning the class A world. There is no real competition at this price point. Tant pis! It's all about margins |
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Post by donh50 on Jun 15, 2018 22:28:47 GMT -5
Random thoughts... IIRC, Emotiva said they ran out of stock but went ahead and made one more run of the XPA-1, or perhaps had one more run in process, so there was an initial group that shipped "immediately" and a second batch that is being shipped from overseas thus the delay. I do remember those big old speakers, and if memories of my long ago grad acoustics classes are correct, to gain high efficiency with a big woofer means a big box or horn-loaded (or transmission line) cabinet. Speaker design is not my day job; more high-speed/RF/mW analog circuits. A friend of mine had a big Bozak system that was unbelievable to my young ears. And of course every college EE department had to have at least one if not several VoT wannabees with varied success. I was lucky enough to have a prof who owned the real thing. And another who had Beveridge, etc. Was it the LS3/5a that started the trend of having bookshelf speakers reach the lower bass region? By killing the sensitivity, natch, to get more output from the little woofer by dropping the effective sensitivity of the mid/tweeter driver. Most speakers assume a voltage source is driving them, so to calculate the sensitivity over frequency means knowing the impedance over frequency, not just the frequency response (magnitude). It has been ages but I have a vague memory of the IHF using 1 kHz for sensitivity (and a lot of other things) just to provide a metric. Not 100% sure -- I passed the test, got my license (as an audio consultant), but that again was long, long ago (but in this galaxy, if that helps me any  ). I know some folk used pink noise to generate an average sensitivity number but am not sure that is used much today (pink noise is equal energy per octave, often used for audio testing, and helps -- but does not stop -- save the tweeters that would probably fry exposed to white noise for long periods of testing). All IME/IMO/FWIWFM/my 0.000001 cent (microcent) - Don |
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Post by DavidR on Jun 16, 2018 9:58:04 GMT -5
Random thoughts... IIRC, Emotiva said they ran out of stock but went ahead and made one more run of the XPA-1, or perhaps had one more run in process, so there was an initial group that shipped "immediately" and a second batch that is being shipped from overseas thus the delay. I do remember those big old speakers, and if memories of my long ago grad acoustics classes are correct, to gain high efficiency with a big woofer means a big box or horn-loaded (or transmission line) cabinet. Speaker design is not my day job; more high-speed/RF/mW analog circuits. A friend of mine had a big Bozak system that was unbelievable to my young ears. And of course every college EE department had to have at least one if not several VoT wannabees with varied success. I was lucky enough to have a prof who owned the real thing. And another who had Beveridge, etc. Was it the LS3/5a that started the trend of having bookshelf speakers reach the lower bass region? By killing the sensitivity, natch, to get more output from the little woofer by dropping the effective sensitivity of the mid/tweeter driver. Most speakers assume a voltage source is driving them, so to calculate the sensitivity over frequency means knowing the impedance over frequency, not just the frequency response (magnitude). It has been ages but I have a vague memory of the IHF using 1 kHz for sensitivity (and a lot of other things) just to provide a metric. Not 100% sure -- I passed the test, got my license (as an audio consultant), but that again was long, long ago (but in this galaxy, if that helps me any ). I know some folk used pink noise to generate an average sensitivity number but am not sure that is used much today (pink noise is equal energy per octave, often used for audio testing, and helps -- but does not stop -- save the tweeters that would probably fry exposed to white noise for long periods of testing). All IME/IMO/FWIWFM/my 0.000001 cent (microcent) - Don I believe it was Edgar Villchur, founder of Acoustic Research, with the AR1 and followed by the AR2 and 3 |
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). I know some folk used pink noise to generate an average sensitivity number but am not sure that is used much today (pink noise is equal energy per octave, often used for audio testing, and helps -- but does not stop -- save the tweeters that would probably fry exposed to white noise for long periods of testing).