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Post by Gary Cook on Jan 22, 2014 1:28:04 GMT -5
Need some help here guys, I need a subwoofer amp and my preference would be keeping with the Emotiva appearance.
The current status is I have a single 17" subwoofer, 145 litre vented cabinet, tuned for 25hz, which is powered by a stand alone 400 watt into 4 ohms Class AB DIY amp. Which if I remember rightly I built around 1998, so it's 15 or maybe 16 years old. I chose 400 watts to align with my rule of thumb which says 4 to 5 times the sub woofer watts compared to the other 5. This was OK when I had a 100 wpc (really ~80 wpc) AVR, but now I have a 200 wpc (really 200+ wpc) XPA-5. So I figure it's time for a power amp quality upgrade, maybe not necessarily a grunt upgrade.
The question is what Emotiva amps should I consider;
An XPR-1 would be seriously over kill, quality and quantity.
An XPA-1 would do it, 1KW into 4 ohms, but a bit of a quality overkill, like feeding strawberries to pigs. Plus all that Class A goodness would be wasted.
An XPA-2 bi amped would also do, similarly 1KW into 4 ohms, but still a bit of a quality overkill, like feeding a donkey those same proverbial strawberries. Not so much Class A waste though.
An XPA-100 possibly not enough grunt with 400 watts into 4 ohms, similar to what I have currently. But no doubt a step up in quality. Not totally eliminated.
An XPA-200 bi amped (can I do that with an XPA-200?), that would give me 480 watts (maybe) into 4 ohms, a little bit more than what I have currently. But again no doubt a step up in quality. Also not totally eliminated.
A UPA-200 bi amped, (can I do that with a UPA-200?), possibly not enough grunt with 400 watts (maybe) into 4 ohms, similar to what I have currently. But again no doubt a step up in quality. Also not totally eliminated.
Left field, I'm seriously contemplating a pair of XPA-1L's for the FL&FR and then using the 2 freed up channels on the XPA-5 for Zone 2. To avoid the duty and GST issue I would get the XPA-1L's separately, with a few weeks in between. So what I was thinking was trying the first XPA-1L in Class AB (500 watts into 4 ohms) as a subwoofer amp until the second XPA-1L arrived. If it proved to have more than enough grunt then getting an XPA-100, which is pretty close to an XPA-1L in Class AB grunt. Or an XPA-200 bi amped if that's a goer.
Whaddya reckon?
Cheers
Gary
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hemster
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Post by hemster on Jan 22, 2014 1:45:39 GMT -5
I'd go left field!  |
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Deleted
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Post by Deleted on Jan 22, 2014 3:38:37 GMT -5
Re XPR-1, as I understand it we can't get those down to Oz anyway so....
XPA-1 I'd personally go for quality-wise and not worry about any 'overkill' (can one really have overkill?, really??) if I had the quids that is (aussi $ at app 88c grumble, grumble)
XPA- 200 - doesn't seem to have the grunt even bi-amped surely, or am I missing something? Also is the gain the same or is this also not an issue?
sooooo, XPA-1l as you seem to be suggesting.
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Post by Deleted on Jan 22, 2014 4:03:44 GMT -5
Of course the other thing you might consider is building another matching sub to try out the 'twin' effect and buy 2 more XPA-1Ls - you did say you're going for quality..  |
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Post by moko on Jan 22, 2014 4:19:02 GMT -5
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Post by garbulky on Jan 22, 2014 10:18:57 GMT -5
I too think using Emotiva's amps for subs may nopt be the best use of money. But your subs will be in class A at low-mid volumes!  How many can boast that? |
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Post by red5ive on Jan 22, 2014 11:57:40 GMT -5
I'm not a fan of plate amps and prefer external amplification when possible. So, another vote for Left Field. I was contemplating this myself between an XPA-1L and XPA-100 during the holiday sale, but I couldn't come up with the funds. So right now I'm looking at a pro amp, more than likely the Crown XLS1000, bridged into 4 ohm is a whopping 1000W RMS.
Also, I'd take the XPA-2 off the list. The minimum impedance bridged mode is 8 ohm.
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Post by frenchyfranky on Jan 22, 2014 19:09:36 GMT -5
I remember Dan said sometime last year that Emotiva must commercialize a subwoofer amp..... Maybe some of you have a better memory than me.
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Post by Gary Cook on Jan 22, 2014 19:10:42 GMT -5
I have in mind that all of my bass and LFE control is carried out by the USP-1 or the UMC-200, so I have no need for fancy pants cross over and equalisation facilities. My DIY power amp used to have a full preamp stage built in but I removed it some years ago. For me the bottom line is, I just need a power amp. Someone suggested a second sub, which is not something that I would consider. I use my sub as a true sub woofer, not as a substitute for stereo woofers and as a result, at it's operating frequencies, it's completely omnidirectional. Plus at 145 litres there simply isn't room for a second. I've considered the Dayton, it's Class AB and fits the budget OK, even with freight being 50% of the cost of the amp itself. It doesn't have an XLR input which may be an issue as the sub is 5 metres (cable length) from the rack. It also (uniquely in this 3) has a complete case over the internals, a personal preference. The Keiga seems overpriced for a Class D amp and it has a lot of features that I simply will never use. It also doesn't have an XLR input. But thanks for the link it's not one that I had considered previously. The Hypex is one that I had considered previously. Even allowing for the strength of the Hypex name, it also seems overpriced for a Class D amp, albeit slightly less than the Keiga. It similarly has a lot of features that I simply will never use. But it does have an XLR input, that's a plus. None of the above have trigger inputs which is an issue. I'm not a fan of auto on subwoofers, my experience has been that they often have problems, turn on delay and/or complete failure to turn on at low input signal levels. Where my sub is located it is not possible to access a plate amp power switch. I could get a triggered power board but I'd prefer to keep it simple and I do like to plug my power amps direct into the power source. The above is an example of why I have moved my thinking away from a plate amp and back to another stand alone amp. I would still consider a plate amp but I haven't found one with the combination of sufficient grunt, a sealed case, trigger, XLR input and quality sound (for powering a sub woofer). Obviously an Emotiva amp has the unique advantage of looking the same as the rest of the equipment if I do decide a separate amp is the go. Cheers Gary |
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Post by Gary Cook on Jan 22, 2014 19:17:32 GMT -5
I remember Dan said sometime last year that Emotiva must commercialize a subwoofer amp..... Maybe some of you have a better memory than me. Andrew confirmed recently, to a question I asked in another thread, that a sub woofer amp "wasn't off the table". I took that as a longer term response compared to "it's on the table currently". Cheers Gary |
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Post by garbulky on Jan 22, 2014 21:27:07 GMT -5
I think the thing for Emo is twofold.
Most plate amps which is what most of the market goes for is reasonably cheap and produce lots of power. So even if Emotiva's construction is way better and ironclad, it has to compete with the power figures.
Then we come to the price. If they released a 1 kw subwoofer amp at XPA-1 prices, would people buy them in sufficient bulk quantities when there are cheaper plate amps that push those watts. So the pressure is to reduce the price.
And then the rub is....
If they produce a high power, high watt, reasonably solidly built amp at really cheap prices...people would buy them for their regular stereos as monoblock amps maybe even over emo's current amp offerings. And then they end up competing with their own line up which isn't where they want to be at.
I think it's a good thing for Emotiva to offer it but I don't know how realistic it would be.
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Post by Gary Cook on Jan 22, 2014 22:25:31 GMT -5
I think the thing for Emo is twofold. Most plate amps which is what most of the market goes for is reasonably cheap and produce lots of power. So even if Emotiva's construction is way better and ironclad, it has to compete with the power figures. Then we come to the price. If they released a 1 kw subwoofer amp at XPA-1 prices, would people buy them in sufficient bulk quantities when there are cheaper plate amps that push those watts. So the pressure is to reduce the price. And then the rub is.... If they produce a high power, high watt, reasonably solidly built amp at really cheap prices...people would buy them for their regular stereos as monoblock amps maybe even over emo's current amp offerings. And then they end up competing with their own line up which isn't where they want to be at. I think it's a good thing for Emotiva to offer it but I don't know how realistic it would be. I get where you are coming from and I can see the pros and cons. Fundamentally there must be a reason why Emotiva hasn't done a dedicated sub woofer amp to date, after all it's a pretty obvious omission from the range. I built my own a long time ago because there wasn't anything available at that time that did what I wanted. In that 15 or so years since I still haven't seen anything that screams "buy me, buy me". Everything that I have looked at and/or listened to has compromises. What is missing (from my knowledge bank anyway) is whether or not a narrow frequency Class AB amp would be cheaper to produce than a wide frequency Class AB amp. Simplistically (and I mean really simplistically) if Dayton can do 1000 watt Class AB plate amp that sells via Parts Express for ~$US350, then what could Emotiva do selling direct? I get the feeling (not a strong one mind you) that Emotiva are not Class D fans. But if HYPEX at a (Scandinavian expensive) price of $US540 can do an 800 watt sub amp via their distribution network then what could Emotiva do a 1000 watt Class D sub amp for direct sales? I summary I don't think price/performance is the issue. my guess (and its really a guess) is that it's a sales volume decision based on the overwhelming ratio of powered/active subs compared to passive subs. If in the new speaker range Emotiva comes out with a passive sub then a stand alone sub amp has more of a chance. Time will tell on that one. Cheers Gary |
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Post by Chuck Elliot on Jan 22, 2014 22:32:17 GMT -5
Before I decided on the F15HP subs. I was looking at the Crown XLS DriveCore Series Power Amplifiers for a DIY project.
Lots of power for a nice price.
Chuck
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Post by Gary Cook on Jan 23, 2014 0:34:45 GMT -5
Before I decided on the F15HP subs. I was looking at the Crown XLS DriveCore Series Power Amplifiers for a DIY project. Lots of power for a nice price. Chuck Thanks for the suggestion Chuck, I've used Crown amps in professional roles a few times, they work OK, sound OK, have no major problems except the fans are NOISY. Being Class D they do occasionally suffer from EMF interference which can be tricky to solve. Oh, and they have no auto on or trigger. Cheers Gary |
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Post by moko on Jan 23, 2014 8:01:44 GMT -5
the dayton uses class AB and at certain point turn into class G. it's the same topology as outlaw audio uses for their slim monoblock amp. otherwise this plate amp won't be efficient and need big power transformer like xpa-1. for connection i think you can still use xlr cable with some kind of adaptor (balun ?) into the lfe direct input. but if i can diy like you, i would just get a class D amp module with its power supply and use it as a plate amp. with the amp positioned away from gear rack and have better design, EMI can be minimalized. example : connexelectronic.com/product_info.php/cPath/39_41/products_id/139?osCsid=7oagjeb681sfi097r6p3aoii91this stereo module can be bridge to achieve high power into 4 ohms. |
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Post by garbulky on Jan 23, 2014 10:57:20 GMT -5
I think the thing for Emo is twofold. Most plate amps which is what most of the market goes for is reasonably cheap and produce lots of power. So even if Emotiva's construction is way better and ironclad, it has to compete with the power figures. Then we come to the price. If they released a 1 kw subwoofer amp at XPA-1 prices, would people buy them in sufficient bulk quantities when there are cheaper plate amps that push those watts. So the pressure is to reduce the price. And then the rub is.... If they produce a high power, high watt, reasonably solidly built amp at really cheap prices...people would buy them for their regular stereos as monoblock amps maybe even over emo's current amp offerings. And then they end up competing with their own line up which isn't where they want to be at. I think it's a good thing for Emotiva to offer it but I don't know how realistic it would be. I get where you are coming from and I can see the pros and cons. Fundamentally there must be a reason why Emotiva hasn't done a dedicated sub woofer amp to date, after all it's a pretty obvious omission from the range. I built my own a long time ago because there wasn't anything available at that time that did what I wanted. In that 15 or so years since I still haven't seen anything that screams "buy me, buy me". Everything that I have looked at and/or listened to has compromises. What is missing (from my knowledge bank anyway) is whether or not a narrow frequency Class AB amp would be cheaper to produce than a wide frequency Class AB amp. Simplistically (and I mean really simplistically) if Dayton can do 1000 watt Class AB plate amp that sells via Parts Express for ~$US350, then what could Emotiva do selling direct? I get the feeling (not a strong one mind you) that Emotiva are not Class D fans. But if HYPEX at a (Scandinavian expensive) price of $US540 can do an 800 watt sub amp via their distribution network then what could Emotiva do a 1000 watt Class D sub amp for direct sales? I summary I don't think price/performance is the issue. my guess (and its really a guess) is that it's a sales volume decision based on the overwhelming ratio of powered/active subs compared to passive subs. If in the new speaker range Emotiva comes out with a passive sub then a stand alone sub amp has more of a chance. Time will tell on that one. Cheers Gary Good reply. And you make a great point that sales volume may be more the issue than anything. I had no idea that there is something called a narrow vs wide frequency amplifier. Very interesting. Honestly at this point, I never thought Emotiva would come so darn far. With all their really neat upcoming products, they are fixing to be a real giant in the audiophile world IMO. |
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Post by Gary Cook on Jan 23, 2014 21:16:16 GMT -5
the dayton uses class AB and at certain point turn into class G. it's the same topology as outlaw audio uses for their slim monoblock amp. otherwise this plate amp won't be efficient and need big power transformer like xpa-1. for connection i think you can still use xlr cable with some kind of adaptor (balun ?) into the lfe direct input. but if i can diy like you, i would just get a class D amp module with its power supply and use it as a plate amp. with the amp positioned away from gear rack and have better design, EMI can be minimalized. example : connexelectronic.com/product_info.php/cPath/39_41/products_id/139?osCsid=7oagjeb681sfi097r6p3aoii91this stereo module can be bridge to achieve high power into 4 ohms. Thanks for the link, it's not one that I have come across before. Around $US310 (amp plus power supply) + freight for 2.4 killerwasps is not a bad deal. I'll have a serious look at that possibility and do some research. Cheers Gary |
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Post by Gary Cook on Jan 28, 2014 1:03:33 GMT -5
OK, so the Secret Warehouse Sale email this morning forced me to make a call, quickly and an XPA-1L is on the list. Hopefully I was fast enough on the email to secure it or there is more than one.
Cheers
Gary
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Post by Gary Cook on Jan 28, 2014 20:02:53 GMT -5
Bugga, no XPA-1L's left in the Secret Warehouse Sale. So I took a chance and grabbed an XPA-100, not a big risk really. Should be interesting finding out how the XPA-100 works with its 400 watts powering a 4 ohm subwoofer. I have this feeling, in typical Emotiva power amplifier results, it's going to prove to be an inspired choice. I'll for sure post up a review, hopefully in about 6 days.
Cheers
Gary
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Post by Gary Cook on Feb 4, 2014 20:14:30 GMT -5
Well the XPA-100 arrived at work a little while ago, UPS on time 6 days door to door, with a change of delivery address while in transit, can't complain. Just have to get it home and open it up, hopefully the ERC-3 silver trims are in the box too. Then it should be a quick install, unplug the old DIY sub amp, power, RCA input plus speaker cable and then plug the XPA-100 in. I'll write up a review after the weekend of listening.
I like new toys.
Cheers
Gary
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How many can boast that? 
