[Nuance]

Well, hopefully you would be using a high pass filter on the HT2's.  It would be pretty hard to get a smooth blend otherwise, unless the sub was only operating below 30 Hz or so.   But with a high pass filter, and with a crossover in the 60-80 Hz area, you would be taking a lot of the load off of the W18's.  Would this really improve the midrange?  There are more opinions than facts on that one.  But if you ever make it back to Bethesda, you can help me lug my HT3 upstairs and at least see if you can hear much difference in the midrange with the HT2's running full range. 

With an 80Hz crossover point in mind, what would you recommend setting the low pass filter to when using a pair of SongTowers or HT2-TL's and a subwoofer (or 2 or 3 or 4)? 

[DMurphy]

With an 80Hz crossover point in mind, what would you recommend setting the low pass filter to when using a pair of SongTowers or HT2-TL's and a subwoofer (or 2 or 3 or 4)?

I was assuming you would just use 4th order LR slopes and set both low and high pass to 80 Hz.  But those things always take experimentation.

[Saturn94]

Well, hopefully you would be using a high pass filter on the HT2's.  It would be pretty hard to get a smooth blend otherwise, unless the sub was only operating below 30 Hz or so.   But with a high pass filter, and with a crossover in the 60-80 Hz area, you would be taking a lot of the load off of the W18's.  Would this really improve the midrange?  There are more opinions than facts on that one.  But if you ever make it back to Bethesda, you can help me lug my HT3 upstairs and at least see if you can hear much difference in the midrange with the HT2's running full range.

Yes, my Anthem AVM20 processor allows me to apply a high pass filter to the L&R speakers (as well as the center and surrounds, all independently) and a separate low pass filter to the sub.  Also, for each I can choose any setting between 40hz and 165hz (in 5hz increments).

In my current setup, the right speaker position causes a very nasty bump in response around 90hz or 100hz.  I'm limited where I can place my speakers, but I was able to successfully smooth out the response nicely by setting the HPF for the L&R speakers to 160hz and the LPF for the sub to 80hz (for music that is, for HT the Anthem allows you to let all LFE information to be sent to the sub regardless of the LPF setting if desired........I love this processor!).

It's possible I may have to do the something similiar with the crossover settings depending on how the new speakers behave in my room.  So I'm thinking it's not very likely that I will be running the new speakers full range, hence my question about how much alike the HT2-TL and HT3 sound with most of the bass duties handled by the sub.  Your explanation about the different shapes of midrange responses based on the crossover used (2 way vs 3 way) makes sense.

I definately plan to make another trip to Bethesda for more listening (I'll send you an e-mail or PM).  I'll make sure to do my exercises so I can help you lug those speakers upstairs!

[Saturn94]

Just get the SoundScape's and call it a day. Then you'll know you've got the best of the best.

Love your idea!  I'll be happy to accept any donations to make that possible.

[jsalk]

You mention a "nasty bump" in the response of the right speaker.  This indicates to me serious consideration might be given to the HT2-TL's.  We have found transmission line designs quite a bit less sensitive to placement issues like this.

Just a thought...

- Jim

[Saturn94]

You mention a "nasty bump" in the response of the right speaker.  This indicates to me serious consideration might be given to the HT2-TL's.  We have found transmission line designs quite a bit less sensitive to placement issues like this.

Just a thought...

- Jim

Great information to consider.....thanks Jim!

Along those lines, my current speakers are a sealed design; would the TL design be less sensitive to placement than a sealed design?  Perhaps also a factor is the fact that the bass drivers in my ADS are in a different position than the HT2-TL (ADS are closer to the floor than the HT2-TL)?

[jsalk]

I'd hate to speculate on that as we just don't do sealed designs.  So I've never really compared them.

- Jim

[Saturn94]

I'd hate to speculate on that as we just don't do sealed designs.  So I've never really compared them.

- Jim

Thanks.

Any thoughts on this, Dennis?

[ratso]

I was assuming you would just use 4th order LR slopes and set both low and high pass to 80 Hz.  But those things always take experimentation.

dennis, i know this is a real noob question, but i get lost real quick in these discussions. i am also going to run a sub with my HT2-TL's, but the device i will use for bass management just has a simple crossover settings - no provisions for doing high and low pass filtering. i was always under the assumption that that's what a crossover did - sent all the high sounds up top and all the low sounds to the woofer. what does being able to set hi and low filters do for you, and do i need to be able to do this if i want my speakers to sound correct?

[jsalk]

ratso -

When you use a receiver as a processor to control the crossover frequency (say 80Hz) to the subwoofer, it creates a high pass filter for the main speakers and a low pass filter for the subwoofer.  If it does this correctly, it will no longer send bass under 80Hz to the main speakers.  It will send these frequencies to the subwoofer instead.  It should create the appropriate filters for you.

I hope this is what you were referring to.

- Jim

[Nuance]

I was assuming you would just use 4th order LR slopes and set both low and high pass to 80 Hz.  But those things always take experimentation.

Just curious, because my preamp has an adjustable low pass on it.  I currently have it set to 80, so that's good to know.

[Nuance]

I'd hate to speculate on that as we just don't do sealed designs.  So I've never really compared them.

- Jim

Great information to consider.....thanks Jim!

Along those lines, my current speakers are a sealed design; would the TL design be less sensitive to placement than a sealed design?  Perhaps also a factor is the fact that the bass drivers in my ADS are in a different position than the HT2-TL (ADS are closer to the floor than the HT2-TL)?

If they are anything like sealed subwoofers, room gain will play a large roll with the design.  A sealed design rolls off gently, but coupled with room gain you can get some serious amounts of extra depth down low.  Again, this applies to subwoofers only, but might also apply to a sealed speaker...???

[ratso]

ratso -

When you use a receiver as a processor to control the crossover frequency (say 80Hz) to the subwoofer, it creates a high pass filter for the main speakers and a low pass filter for the subwoofer.  If it does this correctly, it will no longer send bass under 80Hz to the main speakers.  It will send these frequencies to the subwoofer instead.  It should create the appropriate filters for you.

I hope this is what you were referring to.


- Jim

yep, so simple! thanx!

[Saturn94]

If they are anything like sealed subwoofers, room gain will play a large roll with the design.  A sealed design rolls off gently, but coupled with room gain you can get some serious amounts of extra depth down low.  Again, this applies to subwoofers only, but might also apply to a sealed speaker...???

Thanks Nuance.  I don't have an issue with really low frequencies (say below 80hz), it's that 90hz to 100hz area that was giving me a problem.  If it were possible to move my seating position back about 3 feet or so (I can't because it would block the front door!) then it wouldn't be an issue since the problem peak drops off back there.  It's also not an option to move the seating position forward either.  I guess I can't complain too much since other than that one problem area, the rest of the band is pretty smooth and my trick with the crossover settings works very well.  As a side note, I have considered refining the bass from the sub by trying a product such as SVS's sub EQ unit (same as Audyssey's sub EQ).

Hopefully another trip to Dennis's should answer more of my questions and help in my quest to upgrade my ADS.

[DMurphy]

Thanks.

Any thoughts on this, Dennis?

Not really.   Thoughts come hard to me.  But to be honest, I can't think of any reason why a TL would be less sensitive to your room mode than a sealed design, unless the sealed box tuning on your ADS's produced a peak in the 90-100 Hz. reason.  And that's very unlikely given the size of your cabinets. 

[Saturn94]

Not really.   Thoughts come hard to me.  But to be honest, I can't think of any reason why a TL would be less sensitive to your room mode than a sealed design, unless the sealed box tuning on your ADS's produced a peak in the 90-100 Hz. reason.  And that's very unlikely given the size of your cabinets.

Thanks Dennis.

So it seems that the only reason the HT2-TL might do better (or just differently) in the problem area would be the difference in position of the bass drivers (the HT2-TLs are higher than the ADS).

[ratso]

hey saturn i have a svs as-eq1 for my HT subs (and also a krk ergo which uses lyngdorf's roomperfect room correction for my 2 channel system) and i think either one would go a long way to fixing your bass response. i am really happy with both. the ONLY drawback i have is unless you have a way of adjusting for delay (like you are using an AVR that corrects for sub distance) then svs recommends using a device with delay like a behringer DCX 2496 along with the eq1. this would drive up the not exactly cheap cost of the eq1 of course. (not sure if this is true with the krk as i don't use it with subs, i just use it to tame the bass on my speakers for now.)

[Saturn94]

hey saturn i have a svs as-eq1 for my HT subs (and also a krk ergo which uses lyngdorf's roomperfect room correction for my 2 channel system) and i think either one would go a long way to fixing your bass response. i am really happy with both. the ONLY drawback i have is unless you have a way of adjusting for delay (like you are using an AVR that corrects for sub distance) then svs recommends using a device with delay like a behringer DCX 2496 along with the eq1. this would drive up the not exactly cheap cost of the eq1 of course. (not sure if this is true with the krk as i don't use it with subs, i just use it to tame the bass on my speakers for now.)

Yes, my processor allows delay adjustments (via distance settings) for all channels including the sub.  Although the SVS sub EQ would help smooth out the bass response from the sub, it doesn't help the problem I mentioned above since it's mainly coming from the R speaker and not the sub.  Does the krk ergo allow correction for just the bass on the L&R speakers without touching the midrange and treble frequencies?  I really haven't looked that hard into room correction devices since my crossover trick seems to work quite well.

[ratso]

yep it does (see below). BTW i have probably learned more about speakers, equalization, and audio in general in the last three days than i have in my whole life up til now when i came across this thread:

http://www.audiocircle.com/index.php?topic=58304.0

it's all good, some of it is pretty technical but the REAL gem as far as i am concerned is the two part article " Maximizing Loudspeaker Performance in Rooms - Why Loudspeakers Sound the Way They Do./Maximizing Loudspeaker Performance in Rooms Part 2 - The Acoustical Design of Home Theaters "

it explains why nulls in bass can't be corrected with equalization (only peaks can) and why equalizers should only try to fix the bottom couple hundred Hz of the FR (the krk only corrects up to 500Hz). hope this helps someone as much as it helped me. it also pointed out that a major factor in making good sounding speakers is having not only strong on-axis frequency response but also strong off-axis response (i thought that only mattered to the people sitting next to you from the 'sweet spot'). i mention this here because salks seem to have excellent off-axis measurements. it also shows that almost no one publishes measurements that are really useful to determining how a speaker will sound in your home (although someone that did it right was tom andry in the audioholics review of the salks).

i should also point out something interesting i came across in an old download of peter aczal's audio critic. in an interview with the designer from NHT ken kantor, he did experiments placing single audio sources in a circle around subjects heads and found that there is naturally in humans less cross-correlation at certain angles. and he found that that the angle that minimizes it the most is 21 degrees. so if you have your speakers at an equilateral triangle from you (30 degrees) a fun experiment is to move them closer together by 10 degrees and see if that WIDENS your soundstage some.

[DMurphy]

Thanks for the link.  Off-axis performance is a very complex subject.  It matters for two reasons.  First, without complete toe-in, the first arrival sound will be off axis horizontally, although the angle won't be very large.  Second, most of the sound we hear is reflected, and the reflections will come from all of the sound that the speaker radiates into the room vertically and horizontally.  So if there is, say, a serious off-axis peak, you will hear that in the reflected sound field.  And if dispersion is very narrow in the highs relative to the mids and lows, you will also hear that.  But--how does the brain process all of these reflections that arrive at different times, reduced strengths, and with different frequency responses.  I don't know.  So it's difficult to predict just how important various departures from flatness will be in the off-axis response.  I mainly check for serious peaks in the horizontal off-axis response, which usually occur in the lower treble where the tweeter's response may be much more dispersed than the upper range of the woofer or mid.