[Gopher]

My VR-1s are paired with an M&K MX-90 and I had a hell of a time getting the sub level/x-over to integrate properly. Now that its at a level I find acceptable, I'm enjoying it emensely (or was until I switched to Rat Shack speaker cable from my AZ Holograms [sold] until my Grover Silver References get here).

 

[mcgsxr]

I have a set of Totem Rokk, matched to a custom Nakamichi sub driven by a 300wt BASH amp.

It took some time to set the crossover on the sub, and place that big beast in the room right, but I have sound in my room now, that I like quite a bit.

For movies, it is a simple twist of the sub volume north of my reference setting, and 2.1 movie sounds decent too.

It can be done, and there are a number of ways to do it, but it takes time and effort - then again, isn't that the point of system matching in the first place?

Good luck with it,

Mark in Burlington

 

[tomek]

Quote:

Originally posted by soupy The bass is really thin in this room if they're played alone than compared to when I have them at home on speakers stands in a living room. The sub really fills up the gap nicely and makes it more musical and fun to listen to.

yes, that about sums it up. I am amazed by the speakers, I sit there and am blown away as things not only image between them, but up and down too. However, a friend of mine was over, a non audiophile, and it's always important to hear from someone not completely immersed in it and lost in the details. He said it was just incredible, but that they didn't make the music as 'fun' as his minivan. now i don't just dismiss that. some bass slam is missing, that's how i would have put it, and it does need to be filled in.

should i try to go to future shop and pair it with a velodyne first to see if i like it? i'm weary of buying a sub and hoping it matches after i've paid for it.

 

[AdamP88]

I've got Axiom M22ti's paired with an SVS PB1-ISD sub, and they work together amazingly well. The sound is quite coherent and with a little calibration it sounds quite seamless.

The SVS is a beast, and handles music just as effortlessly as it handles deep HT stuff. The sub is definitely the best I've ever heard - no boom at all and tight down to 22hz, with loads of headroom. I've yet to hear it strain on ANY material at ANY volume (we've ran tests - this thing can shake pictures off walls if you want it to

). The M22's are also incredible speakers, especially for their very modest price tag ($400). Fantastic imaging, extremely detailed and very neutral, and they don't try and compensate for enclosure size by bumping up the bass, so it rolls off quite naturally and lends itself to pairing with a good sub quite well.

 

[tomek]

i don't think this is off topic, so i'll post it here.

when you talk about pairing your sub with speakers, i keep hearing to make sure it 'rolls of naturally' and the words 'flat'.

what does it mean exactly?

i just compared my old paradigm mini monitors versus my newer speakers, and as i swept down in frequency, i realized why mine are sounding thinner. at 35hz or so (at least according to the software) mine continued their fade away, whereas the mini monitors all of a sudden had deeper bass. is this 'unrealistic' but what most people want in consumer speakers?

do my much much more expensive ones roll off the way they are supposed to? and is this more ideal for matching with a sub?

 

[rsaavedra]

Quote:

Originally posted by tomek the words 'flat'. what does it mean exactly?

If you have the warble tones, measure the response of your speakers from your listening position using an SPL meter (e.g. not just your ears), let's say using the 1KHz tone, which is very commonly used as a reference. If you measure 80dB's, then the ideal is that at any other frequency, your speaker shouldn't measure too far above or below 80dBs. The closest to 80dB all over the frequency range, the "flatter" the response is. The further away it goes higher or lower, the more jagged, less flat the response is.

For example, the minimonitor has listed frequency response as 56Hz - 20KHz +/-2dB. Notice that +/-2dB. It means, all over the frequency range from 56Hz all the way up to 20KHz, the response doesn't measure more than 2dB or -2dB with respect to the average.

Incidentally, that response is measured down to 56Hz. Below the listed minimum frequency in the freq. response specs (in this case 56Hz), usually the bass rolls off. If it's reaching a peak at 35Hz then you are probably measuring at a point of maximum sound pressure in your room, e.g. the result of room acoustics, rather than a true bump in the response of the minimonitor.

Just as an example, here's the freq. response chart of the Ascend Acoustics CBM-170. According to this chart the speaker has a very flat response (+/-2dB) from just below 80Hz all the way up to 20KHz:
http://www.ascendacoustics.com/Main/...cb170specs.asp

 

[ooheadsoo]

I just finished putting together my subwoofer about 5 minutes ago.

The plate amp I used has full 180 degree phase adjustment so it should be able to integrate very well with just about any pair of speakers that have the potential to integrate well. With my CHEAPO POS soldering iron, I couldn't get the binding posts hot enough to melt the solder, after spending about 4 hours trying, so I...uh...decided to go buy some alligator clips...So I'm running my two Peerless 10" woofers in parallel hooked up with alligator clips, and I'm liking it!! I was really worried about my hack job terminal plate too, because...well let's not go there.

I feel I've gotten it integrated pretty well by ear, using a 200-10hz sine frequency tone sweep. Image certainly hasn't suffered, to my ears, so far.

 

[rsaavedra]

Quote:

Originally posted by ooheadsoo The plate amp I used has full 180 degree phase adjustment so it should be able to integrate very well with just about any pair of speakers that have the potential to integrate well.

Ah we didn't mention phase, important indeed. Keep in mind, however, that a sub properly in phase with the mains can still be out of balance in average volume level terms.

 

[ooheadsoo]

The phase control will ensure you don't have any unsightly phase cancellations, while the volume level will level out the overall frequency response.

Just to clarify, I meant that my plate amp has 0 to 180 degree variable phase adjustment. Most amps have either 0 or 180 toggling.

 

[rsaavedra]

Quote:

Originally posted by ooheadsoo Just to clarify, I meant that my plate amp has 0 to 180 degree variable phase adjustment. Most amps have either 0 or 180 toggling.

Exactly, variable is much better. I never mentioned phase because I forgot given the fact that the PDR-12 doesn't have any phase control, not even a toggle switch. Not an issue since I have it at the same distance from the sweet spot with respect to the mains. If in those conditions a phase cancellation is detected between sub and mains, then swapping reds and black speaker cables on the mains (while keeping the colors matched on the speaker outs of the amp) solves that. This swapping I believe is equivalent to 180 degrees phase shift on the mains. That trick wasn't needed in my setup though.

One comment, I have read there can be phase differences (other than 180 degrees) if you connect the sub and the amp to separate power outlets, e.g. located in different places in your room. Not sure about that though.

 

[ooheadsoo]

http://www.rythmikaudio.com/manual/A250_ST.pdf

There's a guide in this manual on phase adjustment. It's not just distance from the sub to your listening position...Crossovers will affect the phase of the speakers, whether they are electrical or acoustic. I don't profess to understand it all, but this gives you some graphs to look at, at least, so you understand what's going on.

 

[rsaavedra]

Quote:

Originally posted by ooheadsoo http://www.rythmikaudio.com/manual/A250_ST.pdf There's a guide in this manual on phase adjustment. It's not just distance from the sub to your listening position...Crossovers will affect the phase of the speakers, whether they are electrical or acoustic. I don't profess to understand it all, but this gives you some graphs to look at, at least, so you understand what's going on.

Their info seems to be quite specific to their sub, though they show general principles that must apply to all subs. The phase changing with the x-over is very universal for all crossover networks, but there are some so called "phase coherent" crossover networks.

 

[ooheadsoo]

That's because the crossover engineer made it coherent

If you're going to mix and match from different companies (more importantly, mix and match designs) then the phase control becomes more important. Some orders of crossovers match each other naturally, like first order crossovers. However, first orders aren't applicable for subwoofers

I believe a 2nd order crossover is supposed to match very well with another 2nd order crossover. So, if the bookshelves were sealed, that would approximate an acoustic second order crossover. And if the sub had a 2nd order crossover, then it would be phase matched. However, a 2nd order crossover on the sub means that the subwoofer will still be audible way into the lower frequency range of the human voice. So there are many design decisions to consider.

 

[tomek]

Oh god, I just got back from Future Shop.

I heard some Velodyne subs and honestly, the sound was not acceptable. I have some quick speakers, and what I heard there was flabby and bloated. Yuck.

I hope that with these 'musical' subs that the results are much better than that, otherwise I'm in trouble.

 

[ooheadsoo]

System matching is really important. I bet Futureshop's setup was anything but well set up. I know my local best buy is HORRIBLE.