Technical questions about subs and crossovers. (Tannoy TS12)

[ItSeffinga]

I have two KRK RP6 monitors that I'm considering for soffit mounting in my (approximately) 11'x15'x8' (W x L x H) studio. However, I don't want to put all the pressure on just those to produce my full frequency range (they only go down to 49Hz anyway), so I'm considering a couple of Tannoy TS12 subs which I would also soffit mount (directly under my KRK RP6's).

Do you guys think the huge difference between the monitors' sizes are going to give me difficulties in keeping the summed response flat at the crossover frequency?

If so, do you think Tannoy TS10's will be any better?

Another concern is the steepness of the crossover. Barefoot said:

"The response of the sub and monitor are basically those of high and low pass filters. The phase response is not flat in the regions above and below the speakers cutoff frequencies. So you can't count on a flat summed response using a generic crossover unless the responses of both speakers extend well above and below the crossover region," and "The best you can do in this case is ensure that the subs and monitors have flat pass bands that overlap by a minimum of 1.5 octaves on either side of the crossover point."

On the Tannoy TS12 and TS10 it's a 2nd order low pass filter for the crossover, so I'm wondering if this is too steep to extend far enough into my KRKs' frequency range. Also, the output crossover on the TS12's output is fixed at 80Hz. So with the KRK low frequency response being 49Hz, it probably (definitely?) won't even extend a full octave into the TS12's frequency range. Is my thinking on this correct?

Another concern: I can always try to contact Tannoy about it (I really don't know what their customer service is like), but do you think it's safe to assume that the high pass filter on the Tannoy's output is going to be 2nd order as well?

One last thing, does anybody else find the -6dB 26Hz low frequency response or "15Hz limit for usable output" (page#11) suspicious? I just can't see this speaker going that low (26Hz) in a real world environment. I'm thinking, due to the -6dB at 26Hz, that 26Hz must be the cutoff frequency for another 2nd order high pass filter. Is there anything I should be concerned about here (other than treating my studio VERY well for this extremely low bass response )?

Hope the links still work when somebody gets around to answering this. Thanks for helping with my ton-o'-questions guys!

-Dany

[Drumdrumdrumdrum]

Hi,

I'm not sure if there are any so called experts floating around the speaker area latly. I've been waiting for a expert to answer my question about Tannoy's for nearly a month.

I do know a few things about subs. I have a set of Blue Sky System One's.

I would not be matching a Tannoy to your KRK's. I would be getting either the RP12s or RP10s which is made to go with your RP6's.

Also you only need one sub. anything below 100Hz is poly-directional. I think thats what it's called? Maybe you could put two RP10's with your set-up but two 12's would be overkill matched to 6 inch sats.

Consider going for a whole new system if you have the $$$. Those KRK's RP's are very cheap speakers. Your speakers are the most important part of the audio chain in my opinion.

You will need to set them up properly. You can do this with any old level meter. There are easy directions for setting up subs and sats on the Blue Sky website but I'm sure KRK would have directions too.

All the best

[gullfo]

i think the challenge for any expert is for a given set of monitors within a given space, the electronics that drive them, and then identifying proper crossover settings are hugely complex and probably not something any single person could give you an absolute answer on, for a given situation, without significant time investment.

that said, the manufacturer should be able to give input on how best to use their equipment, and they may even have experience with other manufacturers' equipment...

[ItSeffinga]

Thanks so much for the responses, guys. I honestly didn't expect any this fast with Barefoot being on an extended unofficial leave from the forums.

I just talked to John in the tech department over at Tannoy and he seems to think that the steep(ish) 2nd order crossovers are actually better to have because of the phase effects that would occur between the TS12s and the RP6s trying to reproduce too much of the same frequencies. And btw, the 80Hz fixed high pass filter on the TS12's output IS 2nd order as well.

Generic crossovers without much room for adjustment (and no adjustment on the TS12 output) they may be, but I seem to be getting different opinions on the necessity of different types of cutoff filters. John does work with Tannoy however, so I have my doubts about the chances of him divulging that he thinks the Tannoy crossovers are any less sophisticated than what might actually be necessary. Although, for whatever it's worth, he did suggest I could possibly use the TS10s if I didn't need that much bass, so... *shrug*

And I totally agree, Glenn. To get it perfect (or maybe even close to flat) involves considerable expense, time and experience (not to mention testing equipment). But for now, I'd like to get "close" and protect myself from any costly mistakes down the road. If I can get my KRKs and maybe the TS12s (which I probably won't need to upgrade for a LOOOONG time unless I go passive) to get me close to a flat summed response at the crossover point now, then at least I can start testing within what I hope to be a well-represented frequency range (TS12=pretty low ) and treating my studio and maybe even start getting some real, marketable work done. Of course, I won't rush if I can prevent a mistake.

I may be way off, though. I guess, basically, what do you guys think is my next step? I've done a lot of research and feel this is my best choice cost-wise and time-wise, as this is something I'm going to be able to afford in the near future and I don't see myself regretting this due to the need for upgrades.

Maybe some external crossovers might end up being necessary.

btw, are there any dedicated studio monitor forums you guys can suggest? All of my searches turn up DIY home theater and stuff like that. Barefoot doesn't seem to come around much these days.

Thanks for any responses, guys. A pleasure as always.

-Dany

[gullfo]

if you have an active crossover, maybe just try it... can you take the 12's back to the store in case you end up thinking the 10's would be better? and you might need to move the subs around a bit as well as play with the delays and frequencies.

[Drumdrumdrumdrum]

A cool little trick I learnt from someone.

Place the sub where you are going to sit. Then move around the room until the sub sounds good (No overbearing bottom end) then mark that spot and bingo, put the sub on the mark. Clever hey?

Using you dB meter will ultimately help with the balance between the sats and sub.

Some other thoughts I have: I got the blueskys because on paper they had the flattest crossover point. However, any speaker has some kind of peak or lull at the crossover point. Thats why people use full range speakers sometimes (like the Auratones) because there is no crossover. This is especial critical when listening to vocals or reverb trails because most mid/tweeter crossovers are right in the middle of the vocal bandwidth. This is also the reason using a few sets of speakers when mixing is advantageous because different speakers will have slightly different colour at the crossover points.

Sometimes I will think something in the middle of the sound spectrum, like the snare, needs some cut around 1kHz then I listen on the NS10s and its cool. So I leave it. I can really see now how only using one set of speakers can make things really complicated and mess up what should have just been left alone. KISS (keep it simple stupid) or was that keep it stupid simple???

All the best,

Cheers

[ItSeffinga]

Cool trick Drum! I'll definitely give it a try.

I'm not completely sure, but the sub should be in the "sweet spot" (that is, the spot from which it sounds the flattest from the listening position) when you do testing prior to treatments, right?

No, Glenn, the place where I intend to get my Tannoys from has a 20% restocking fee plus you have to pay for shipping there and back (ouch! ), but the original price is so much better than anywhere else, I guess I'm willing to take the risk. If it doesn't work out with the KRK's, then I might have to just use them as reference monitors and get some Tannoy Precisions to work with the subs. Doesn't sound so bad, when you think about it.

As far as active crossovers, I don't have any now, but I was thinking about the Rane AC22B. It's 4th order (Linkwitz-Riley) and I won't have to deal with that fixed 80Hz output crossover deal on the TS12. It's also got a delay control, so I can hopefully correct any phase issues due to misaligned monitor-to-sub positions. Frequency control too (obviously), but no resonance. I guess you can't have it all for this cheap.

Then there's the sub mute which is a cool option, but you can also sum the stereo sub outs to mono for one-sub use, which is starting to look like a decent option. I might run the Rane out to just one TS12 for now and get the other later down the road if I decide to.

All of this is still up in the air until I make a definite decision, but if I do go with two TS12's and the Rane crossover, do you think soffit-mounting them into the corner absorbers with the monitors is an option? Everybody seems to be talking about room placement, but I was thinking that soffit-mounting would get me to a more reliable response, not to mention that it would eliminate any potential phase issues (at least, that's my understanding).

Thanks again guys.

-Dany

[ItSeffinga]

I should probably mention that my current plans for studio treatments (we'll see what they're like after testing) are something like this. The clouds are on a hidden layer, so you can't see them.

Those are supposed to be Event ASP8's, btw. I haven't edited my Sketchup for the soffit-mounted KRK's and Tannoys yet (if ever), so just use your imagination.

[ItSeffinga]

I've got the crossover, so I think I'm going to just go ahead and get one of those TS12s and see how it works out. I'll let you guys know.

Thanks,
Dany