KeithL
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Post by KeithL on Nov 13, 2013 10:35:36 GMT -5
Many subs, including our (now discontinued) X-Ref series, have their own low pass filter (the sub's half of bass management) built in. When you use those subs with a component that includes bass management (like a pre/pro), you disable the bass management in the sub. However, you can simply connect a full-range input to the sub and use it's built in bass management to block out frequencies that it shouldn't be reproducing. The only "catch" is that "full" bass management also prevents your main speakers from receiving the low frequencies that the sub is receiving. Normal "full" bass management routes the low frequencies to the sub and everything else to the mains. If your mains are small, by keeping the bass from reaching them, it lets them do a better job on the other stuff. (Trying to handle bass that is beyond their capabilities can cause small speakers to distort, or even damage them, as well as simply "wasting" the power from the amplifier.) Since our Airmotivs are full range speakers, they don't "mind" getting low frequencies... although, with full bass management, they will be able to play a lot louder. This means that, especially in a small system, or a desktop system, it won't hurt anything to let the full range signal reach both speakers; and simply let the bass management in the sub limit its high frequency response; and let the Airmotivs play the full frequency range. (You always want to limit the high frequencies played by the sub. If the sub doesn't get some sort of bass management, and tries to reproduce frequencies above about 100 Hz, it will cause two problems. First, most subs sound horrible trying to play higher frequency content. Second, we humans can tell the direction that sound is coming from above about 100 Hz. So, unlike low bass, if the sub is playing frequencies much above that, you will be able to hear that the sound is coming from both the mains and the sub, which will mess up the sound stage. This is why, if your sub doesn't have a built-in crossover, you really should use an external one.) External passive crossovers (that go between the preamp and the sub and Airmotivs) can be bought for under $50, and will allow you to get good sound with a sub taht doesn't include its own bass management. HLabs is one company that makes them (they can be bought direct, and some of their models can be bought through Parts Express) www.hlabs.com/products/crossovers/index_files/Page384.htmPlease elaborate. I have no idea what you're saying.
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KeithL
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Post by KeithL on Nov 13, 2013 10:52:48 GMT -5
Just to clear up the confusion for some people..... Back in the old days (you know: horses, hot air balloons, no home theater - only stereo), most powered subs had bass management built in. Most had at least an adjustable low pass filter; some even had full bass management (you connected the preamp to the sub, and it had outputs to go to your main amp right on the sub), and most had a PAIR of line level inputs (one for each channel). There were even passive subs, with all sorts of crossover options. Now, many subs are pretty much intended to be used with a home theater setup - which includes a pre/pro - so they may not include any bass management, and may only have one input. If you have one of those, and you don't plan to use it with a HT pre/pro, your reasonable options are somewhat limited: 1) You can buy an external active crossover (they are difficult to find, the cheaper ones usually don't sound very good, and the good sounding ones tend to be very expensive) - and they can be very complicated to set up correctly. 2) You can get one of the few preamps out there that includes full bass management (like our XSP-1 and USP-1). 3) You can put a passive (line level) crossover between the output of the preamp and the inputs of your power amps and/or sub. HLabs is one company that makes those (they can be bought direct, and some of their models can be bought through Parts Express) www.hlabs.com/products/crossovers/index_files/Page384.htm Again, note, in a small system with Airmotivs, you still need a low pass filter on the sub, but a high-pass filter on the mains is optional. (Personally, I still recommend it, but it isn't strictly necessary. The HLabs model I linked to includes BOTH in one unit for about $50.) 4) (Some of you may notice that I DIDN'T list "use a passive sub and a speaker level passive crossover for the sub" as an option - because there are so many down-sides to that option that I really don't consider it to be "reasonable" for most folks.) SOME MORE ADDED EXPLANATION: All of this was referring to subs THAT DON'T HAVE BUILT-IN BASS MANAGEMENT. As long as your sub DOES have its own low-pass filter, and a pair of stereo line-level inputs, and your main speakers can happily be run full range, then it will work just fine. Got the DC-1 hooked up direct to my amps. Listened to some very familiar CDs. No conclusion yet. I like a sub with my 2 channel and I can't use my sub with this dac so not sure what I'll end up doing. As someone who has run 2.1 for decades, I agree, subwoofer management is essential. Cheers Gary
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Post by gravi on Nov 13, 2013 11:11:17 GMT -5
Thanks for the explanation. So the conclusion is that just a DAC like XDA-2 connected to a power amp cannot be used in a 2.1 system, you have to use one of the alternatives listed. Put it another way, the DAC/Amp combo is only if you have full range speakers or you are satisfied playing music without a sub. Another question - when both the XDA-2/DC-1 units and a pre-amp like USP-1 have volume controls, is that a problem to manage? Just to clear up the confusion for some people..... Back in the old days (you know: horses, hot air balloons, no home theater - only stereo), most powered subs had bass management built in. Most had at least an adjustable low pass filter; some even had full bass management (you connected the preamp to the sub, and it had outputs to go to your main amp right on the sub), and most had a PAIR of line level inputs (one for each channel). There were even passive subs, with all sorts of crossover options. Now, many subs are pretty much intended to be used with a home theater setup - which includes a pre/pro - so they may not include any bass management, and may only have one input. If you have one of those, and you don't plan to use it with a HT pre/pro, your reasonable options are somewhat limited: 1) You can buy an external active crossover (they are difficult to find, the cheaper ones usually don't sound very good, and the good sounding ones tend to be very expensive) - and they can be very complicated to set up correctly. 2) You can get one of the few preamps out there that includes full bass management (like our XSP-1 and USP-1). 3) You can put a passive (line level) crossover between the output of the preamp and the inputs of your power amps and/or sub. HLabs is one company that makes those (they can be bought direct, and some of their models can be bought through Parts Express) www.hlabs.com/products/crossovers/index_files/Page384.htm Again, note, in a small system with Airmotivs, you still need a low pass filter on the sub, but a high-pass filter on the mains is optional. (Personally, I still recommend it, but it isn't strictly necessary. The HLabs model I linked to includes BOTH in one unit for about $50.) 4) (Some of you may notice that I DIDN'T list "use a passive sub and a speaker level passive crossover for the sub" as an option - because there are so many down-sides to that option that I really don't consider it to be "reasonable" for most folks.) As someone who has run 2.1 for decades, I agree, subwoofer management is essential. Cheers Gary
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cgolf
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Post by cgolf on Nov 13, 2013 11:15:47 GMT -5
The DC-1 has a fixed volume setting so it can be controlled through the volume control of a pre-amp. Not sure about the XDA-1 & 2.
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Post by audiobill on Nov 13, 2013 11:22:46 GMT -5
Thanks for the explanation. So the conclusion is that just a DAC like XDA-2 connected to a power amp cannot be used in a 2.1 system, you have to use one of the alternatives listed. Put it another way, the DAC/Amp combo is only if you have full range speakers or you are satisfied playing music without a sub. Another question - when both the XDA-2/DC-1 units and a pre-amp like USP-1 have volume controls, is that a problem to manage? Just to clear up the confusion for some people..... Back in the old days (you know: horses, hot air balloons, no home theater - only stereo), most powered subs had bass management built in. Most had at least an adjustable low pass filter; some even had full bass management (you connected the preamp to the sub, and it had outputs to go to your main amp right on the sub), and most had a PAIR of line level inputs (one for each channel). There were even passive subs, with all sorts of crossover options. Now, many subs are pretty much intended to be used with a home theater setup - which includes a pre/pro - so they may not include any bass management, and may only have one input. If you have one of those, and you don't plan to use it with a HT pre/pro, your reasonable options are somewhat limited: 1) You can buy an external active crossover (they are difficult to find, the cheaper ones usually don't sound very good, and the good sounding ones tend to be very expensive) - and they can be very complicated to set up correctly. 2) You can get one of the few preamps out there that includes full bass management (like our XSP-1 and USP-1). 3) You can put a passive (line level) crossover between the output of the preamp and the inputs of your power amps and/or sub. HLabs is one company that makes those (they can be bought direct, and some of their models can be bought through Parts Express) www.hlabs.com/products/crossovers/index_files/Page384.htm Again, note, in a small system with Airmotivs, you still need a low pass filter on the sub, but a high-pass filter on the mains is optional. (Personally, I still recommend it, but it isn't strictly necessary. The HLabs model I linked to includes BOTH in one unit for about $50.) 4) (Some of you may notice that I DIDN'T list "use a passive sub and a speaker level passive crossover for the sub" as an option - because there are so many down-sides to that option that I really don't consider it to be "reasonable" for most folks.) Well, I run my powered subwoofer with built-in crossover directly off DC-1 analog output!
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Deleted
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Post by Deleted on Nov 13, 2013 11:27:34 GMT -5
that^ would be grand if I didnt need to use the same sub for my LFE out for bluray movies so I guess I am running without a sub for 2 channe;l or buying a 900$ premap (xsp...i had the usp but want/need XLR)
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KeithL
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Post by KeithL on Nov 13, 2013 11:34:54 GMT -5
I fear that I created some confusion with that post (I modified it). As long as your main speakers can happily be run full range, and your sub DOES have bass management, and has left and right line level inputs, you can us use them as-is with a DAC. You WILL lose the benefit of having bass management on your main speakers - but, as long as they run well full range, that is not a problem per-se. (If your mains don't like low bass, it's simple enough to add a pair of passive in-line high-pass filters - for about $30.) To answer your question: Since the volume controls in both DACs are analog (and so won't produce distortion or grain), it's not a problem at all. In that situation, most people prefer to leave the volume control in the DAC alone and simply use the volume control in the preamp. You would probably want to set the volume in the DAC to 0 dB (not to "maximum" - which is rather a high output level). Thanks for the explanation. So the conclusion is that just a DAC like XDA-2 connected to a power amp cannot be used in a 2.1 system, you have to use one of the alternatives listed. Put it another way, the DAC/Amp combo is only if you have full range speakers or you are satisfied playing music without a sub. Another question - when both the XDA-2/DC-1 units and a pre-amp like USP-1 have volume controls, is that a problem to manage? Well, I run my powered subwoofer with built-in crossover directly off DC-1 analog output!
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Post by AudioHTIT on Nov 13, 2013 11:41:35 GMT -5
So the conclusion is that just a DAC like XDA-2 connected to a power amp cannot be used in a 2.1 system, you have to use one of the alternatives listed. Put it another way, the DAC/Amp combo is only if you have full range speakers or you are satisfied playing music without a sub. Another question - when both the XDA-2/DC-1 units and a pre-amp like USP-1 have volume controls, is that a problem to manage? Again, if your sub(s) have low pass filters and level controls (which many do), then you can hook them to either of these DACs. If your subwoofers have high level inputs, low pass filters and level controls (which some do), you can hook them to your power amp. Your conclusion is only valid for specific subs. It's not a problem to have multiple volume controls, you just leave the DAC set at a reference level and use the preamps control.
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KeithL
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Post by KeithL on Nov 13, 2013 11:53:34 GMT -5
There are other ways, but they get complicated.... and they all have pros and cons. 1) Some subs have both balanced and unbalanced inputs - if so, you could leave the DAC connected to one set of inputs and the AVR to the other. 2) You could install a simple RCA-RCA manual switch on the input of the sub so you can switch it between getting its input from the DAC and from the AVR 3) If you wanted to be real fancy, you could install an electrically operated switch (and use a trigger from the AVR to switch the sub input between it and the DAC) 4) You could leave the sub attached to the AVR, send the output of the DAC BOTH direct to the amps and to the AVR, then let the AVR the sub (the sub isn't that critical, so the AVR probably won't mess it up too much). that^ would be grand if I didnt need to use the same sub for my LFE out for bluray movies so I guess I am running without a sub for 2 channe;l or buying a 900$ premap (xsp...i had the usp but want/need XLR)
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Deleted
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Post by Deleted on Nov 13, 2013 12:08:58 GMT -5
4) You could leave the sub attached to the AVR, send the output of the DAC BOTH direct to the amps and to the AVR, then let the AVR the sub (the sub isn't that critical, so the AVR probably won't mess it up too much). ok let me wrap my head around this one....as this seems the most feasable.. I connect DC1 -> xpa-1's by XLR.....DC1->AVR by RCA (cd in)...put the AVR on cd output..and it will send the bass managed <80hz signals to the sub... does that sound right? my only issue as it stands...is I use the analog in's on the DC1 as a HT bypass (sans the sub..that goes direct to sub from avr) does this make sense? i feel im missing somthing...I cant wrap my head around this for some reason...
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cgolf
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Post by cgolf on Nov 13, 2013 12:47:32 GMT -5
4) You could leave the sub attached to the AVR, send the output of the DAC BOTH direct to the amps and to the AVR, then let the AVR the sub (the sub isn't that critical, so the AVR probably won't mess it up too much). ok let me wrap my head around this one....as this seems the most feasable.. I connect DC1 -> xpa-1's by XLR..... DC1->AVR by RCA (cd in)...put the AVR on cd output..and it will send the bass managed <80hz signals to the sub...does that sound right?my only issue as it stands...is I use the analog in's on the DC1 as a HT bypass (sans the sub..that goes direct to sub from avr)does this make sense? i feel im missing somthing...I cant wrap my head around this for some reason... If you hook the DC-1 to your AVR through analog connections, won't that defeat the use of the DC-1 by having the AVR's dacs in operation? Or am I missing something. I didn't run the DC-1 through my UMC-200 because I don't want the UMC getting in the way of the DC-1. Make sense??
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Post by danny01 on Nov 13, 2013 14:19:01 GMT -5
ok let me wrap my head around this one....as this seems the most feasable.. I connect DC1 -> xpa-1's by XLR..... DC1->AVR by RCA (cd in)...put the AVR on cd output..and it will send the bass managed <80hz signals to the sub...does that sound right?my only issue as it stands...is I use the analog in's on the DC1 as a HT bypass (sans the sub..that goes direct to sub from avr)does this make sense? i feel im missing somthing...I cant wrap my head around this for some reason... If you hook the DC-1 to your AVR through analog connections, won't that defeat the use of the DC-1 by having the AVR's dacs in operation? Or am I missing something. I didn't run the DC-1 through my UMC-200 because I don't want the UMC getting in the way of the DC-1. Make sense?? Only the subs are going through the UMC which will do an AD/DA conversion.. Speakers' amps are getting the signal directly from the dc1.. Sent from my HTC6500LVW using proboards
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Post by danny01 on Nov 13, 2013 14:23:24 GMT -5
Although I haven't tried the Harrison filters, I have tried their attenuators, and I didn't like how they altered the sound. If you want a high pass filter for your mains and are you the balanced connections, the fully balanced Marchand XM46XLRA looks like a good option. It costs more, but is still way cheaper than an XSP1.
Sent from my HTC6500LVW using proboards
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cgolf
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Post by cgolf on Nov 13, 2013 15:35:15 GMT -5
If you hook the DC-1 to your AVR through analog connections, won't that defeat the use of the DC-1 by having the AVR's dacs in operation? Or am I missing something. I didn't run the DC-1 through my UMC-200 because I don't want the UMC getting in the way of the DC-1. Make sense?? Only the subs are going through the UMC which will do an AD/DA conversion.. Speakers' amps are getting the signal directly from the dc1..Sent from my HTC6500LVW using proboards So both the DC-1 & UMC are on at the same time. UMC controls the sub volume & DC controls the speakers?
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Post by danny01 on Nov 13, 2013 19:44:00 GMT -5
The DC1 will control both RCA and for volumes at the same time with it's volume control. Setting the UMC's volume control to match the mains then using only the DC1 to control volume will work. I don't think this is the moat ideal solution but it will work. If he can find a unidirectional y cable(I forgot exactly what these are called but they do exist. Regular Y adapter can damage the dac and prepro) to feed the signal from both the UMC and the DC1 to the sub, then the UMC and dc1 won't have to be on at the same time.
Sent from my HTC6500LVW using proboards
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Post by lsdeep on Nov 13, 2013 21:37:07 GMT -5
LOL, i would like to have your probs! my DC-1 is sitting in NYC at the moment and waiting for a friend of mine to bring it with him when he comes to visit mid of december!!! i am kind of sleepless (well that's overdoing it, just a little), but it saves me a sh*tload of money on shipping and duty (roughly another $300). so i guess i can wait and in the meantime figure out what all i can do with the $300 cheers, L
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Post by GreenKiwi on Nov 13, 2013 22:17:47 GMT -5
danny01 I think that one can find summing cables that would probably do the trick.
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Post by gravi on Nov 14, 2013 9:25:46 GMT -5
ok let me wrap my head around this one....as this seems the most feasable.. I connect DC1 -> xpa-1's by XLR..... DC1->AVR by RCA (cd in)...put the AVR on cd output..and it will send the bass managed <80hz signals to the sub...does that sound right?my only issue as it stands...is I use the analog in's on the DC1 as a HT bypass (sans the sub..that goes direct to sub from avr)does this make sense? i feel im missing somthing...I cant wrap my head around this for some reason... If you hook the DC-1 to your AVR through analog connections, won't that defeat the use of the DC-1 by having the AVR's dacs in operation? Or am I missing something. I didn't run the DC-1 through my UMC-200 because I don't want the UMC getting in the way of the DC-1. Make sense?? No, I believe if you use an analog input or the multi-channel in on the UMC-200, the signal stays in the analog domain without undergoing any conversion.
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Post by milsap195 on Nov 14, 2013 11:23:50 GMT -5
Has anybody done a side by side comparison between the xsp and dc-1 as a preamp. I have found that I really dont need all the extra functions of my xsp-1, thinking of replacing it with the dc-1.
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cgolf
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Post by cgolf on Nov 14, 2013 18:46:43 GMT -5
What is the difference in these hookups? Besides the order they are hooked up of course. What's the effect on SQ and who is doing the processing? I want to keep my DC-1 but I also want to have the sub with my 2 channel music. 1. OPPO 95 to DC-1 -- DC-1 hooked directly to amps. Black and white, no sub. 2. OPPO to DC-1 -- DC-1 to UMC-200 7.1 -- UMC to amps. No sub with 7.1 direct so why even do this?? 3. OPPO to DC-1 -- DC-1 to UMC analog -- UMC to amps. Wouldn't this negate the DC-1 and use the UMC dacs? 3. OPPO to UMC -- UMC to DC-1 -- DC-1 to amps. Could this work and could I use the sub this way?
Just confused with all this. I want to keep the DC-1 but I won't if I can't have the sub running also.
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