AR-LST Project

[Aadams]

52 minutes ago, meta_noia_fot said:

Is this what you had in mind

Yes, the height is good.  I did not know you had so little wall but you are at a good starting point.  As long as the cabinet is flat against the wall the woofer will see it as as a baffle extension.   Note, you are already so close to the corner you may get a noticeable bass peak. If the right (or left) side of the cabinet is within a woofer diameter of your window wall it will behave as if placed in the corner.   If you don't like the bass, you could probably bring the speaker toward you to the wall break and still have enough wall for the baffle, and maybe get smoother response.  Your ears will tell you.  The gabled ceiling gives the room some good irregular dimensions to minimize room modes.   Looking forward to your report. 

Adams

JIC your interested -- this link to the library copy of the Roy Allison engineering paper, "The Influence of Room Boundaries on Loudspeaker Power Output"   http://www.classicspeakerpages.net/library/allison/other/technical_articles_by_roy_f/

 

 

[meta_noia_fot]

@AadamsMy kid’s nap was extra long today so I got a couple good hours of listening in. I had them in my original position then moved them out from the front wall once I saw your reply. Your placement is much better. They are now greater than a woofer diameter from the wall.

It still feels too early to say after only a couple hours of listening, but these speakers may be the best I’ve ever put in that room. The reflected sound from the front side tweeter and mids makes the whole front wall sound alive. The LST is a really exceptional system. They may just stay in the music room after all. 

I can’t wait to put in some more listening time. I’ll have to a/b them against my -9s if I can place those in the room too without either’s placement affecting the other’s response. I’m also still going to try them in my living room.

Thanks a ton for your advice @Aadams. I’ll definitely check that Allison article out. 

[Aadams]

19 hours ago, meta_noia_fot said:

Thanks a ton for your advice @Aadams. I’ll definitely check that Allison article out. 

Your welcome, but on this topic I am just passing along the help I received over the years from @Pete B,@tysontom, @Steve F and some other member names I can't recall now.  

PS

I am not sure you have enough listening space to hear the real difference between the AR9 and LST, at least not from a single listening position.

[meta_noia_fot]

@AadamsI was just going through older LST threads this morning. (For some reason, the search bar on this site omits tons of relevant results. I found much more info doing a google search of CSP.) I found much useful info from many names, some still posting here and not. I love the wealth of info on this board. 

I agree that putting the -9’s in the same space won’t work correctly. I was in the space last night and it just doesn’t seem like it would fit. The angled mids and tweeter of the LST’s would be firing right at the -9 baffle instead of the wall. 

I’ve started that Allison article and am working through it. It’s on the advanced side for me but I hopefully I’ll glean some useful knowledge from it. 

——

I have six hours and counting listening to the LST’s in this space; long enough to get a feel for how they sound in the room. Here are some subjective observations.  

The LST’s are 29” off the ground and the outer edge of each cabinet is 17.5” from the wall. The front baffles are 77” from each other. The baffle angled towards the wall is 29” from the wall. They are being powered by a Luxman LV-105u rated at 170w/ch into 4ohms. Mostly vinyl listening on a AT-VMN750SH Shibata stylus on a AR “The Turntable.” Some listening comparisons with streaming sources. 

I am having difficulty describing exactly how they sound, but there is a “presence” I’ve never heard from a speaker in this room. I was listening to the recent stereo reissue of Blue Train and I was truly stunned when Coltrane started his first solo chorus. It sounded as “live” as I’ve ever heard a recording in this room become. I play saxophone and know what a saxophone sounds like in this room. This sounded like a saxophone playing in my room in a way I’ve not heard from a speaker. It was a marvel for me. 

I have experimented with the spectral knob and find that somewhere between 4-6 works best depending upon musical material. Anything with a higher balance for the mids and tweeters sounds too bright in this room. 

The bass response is overall quite good but I’m withholding judgement until after I get the proper woofers in the cabinets. The -9 woofer is stiffer than the -3a. They sound like the woofer section of the -3a though, which makes sense since have the same cabinet volume. I do miss the bass of the -9’s which handles my favorite bass test tracks effortlessly.  

As a piece of furniture, the LST’s work so much better for the room. Enjoying music from the -9’s in such a small room involves a small sweet spot. And not having the -9’s dominate half the room is a breath of fresh air. The LST’s will blend into the room by comparison once I get actual stands instead of using an excellent KLH product as stands. And I’m a pacer; I walk the room often when I listen. I feel like I can use more of this room than I could before with the design and placement of these speakers.

A user of this group kindly sold me a Crown 1002 recently. Once it arrives I’ll have all the power I need and can do an amp comparison as well.

Fun stuff. Nice way to spend a weekend. 

[Aadams]

20 minutes ago, meta_noia_fot said:

And I’m a pacer; I walk the room often when I listen. I feel like I can use more of this room than I could before with the design and placement of these speakers.

The LSTs are perfect for your listening habits.

 

20 minutes ago, meta_noia_fot said:

A user of this group kindly sold me a Crown 1002 recently.

Excellent choice.

20 minutes ago, meta_noia_fot said:

I do miss the bass of the -9’s which handles my favorite bass test tracks effortlessly.  

The LST gives up little to the 9.  Very few recordings play lower than the 3db down point of an LST with optimum placement.  

22 minutes ago, meta_noia_fot said:

have experimented with the spectral knob and find that somewhere between 4-6 works best depending upon musical material. Anything with a higher balance for the mids and tweeters sounds too bright in this room.

From C5 to C8 you are hearing the mids predominantly over tweeters, which are almost exclusively dedicated to high harmonics.  When you rebuild the tweeters you will add a feeling of more space and clarity.

[meta_noia_fot]

22 minutes ago, Aadams said:

The LST gives up little to the 9.  Very few recordings play lower than the 3db down point of an LST with optimum placement.  

I’m being very nitpicky. I can only really tell a difference on tracks with very low, present bass. Some tracks I’ve mentioned on here before like “1st 44” by Aphex Twin and William Albright’s “Organbook II” are noticeably different from the -9. I was just listening to “Limit to Your Love” by James Blake on my LSi’s in the living room the other night and the bass is better defined on the LSi’s than the LST’s. It’s not much but they do hit different on the right tracks. 

I look forward to having the tweeters rebuilt. It’s going to have to wait for a bit though. Thankfully they sound incredible in the meantime. 

[meta_noia_fot]

Just a quick update on placement. I noticed that Model Twelves formed a little cubbyhole in the corner of the front walls. The bass was also more pronounced standing between the woofers and off the front wall. I stopped using the Twelves as stands and replaced them with a couple of 24" pedestal stands. The previous owner of the LST's threw the stands in at no charge, but I was hesitant to use them as they're not the sturdiest looking stands. Still, I sat on them and they held my weight so I'm temporarily using them until I get a more permanent solution. Eventually I would like to wall mount these.

The sum of all this is that the bass is much more present in the whole room. I agree @Aadams that the LST gives up little to the -9's on bass now that I have them with more proper placement. The sound is different enough from before that I now set the Spectral Balance knob to the 2 setting (flat) as a default.

[Aadams]

2 hours ago, meta_noia_fot said:

LST gives up little to the -9's on bass now that I have them with more proper placement. The sound is different enough from before that I now set the Spectral Balance knob to the 2 setting (flat) as a default.

Nice work.  I think you have effectively implemented 2pi placement as depicted in the Allison paper.

For the LST the minimum dimension from woofer center to baffle edge is the same or a bit greater than the depth of the cabinet which, as Allison showed, makes it act like it is in the wall when it is against the wall.

The AR9 implements the placement shown below to achieve flat bass and extends a bit deeper because of the crossover and dual woofers.

Are you using the Crown?

[meta_noia_fot]

2 hours ago, Aadams said:

Are you using the Crown?

Not yet on the LSTs. The Crown has been in the living room on my LSi's since it came in a week or so ago. I ran into the limits of my music room's integrated amp. That model does not have a true pre-out so I have not been able to do an amp comparison. But, that Crown is performing terrifically on the LSi's. It's the most powerful amp I've owned by a good margin and it shows. That's the amp that sees the most work throughout the day and I'm very pleased with how it sounds. It's rare that I put real heavy power into the living room speakers, but that amp allows me to push to any sane listening level and further. Heck of a step up from the built-in A/V amps, which are rated at 60W into 6 ohms (4 ohm compatible). Once I get my Perreaux preamp back from the shop I will be able to try the Crown with the LSTs.

I've actually been revisiting your excellent Music Streaming as a System Upgrade thread this past week. Thanks to Fantasia 2000, my toddler is in a heavy classical music phase right now and I'm encouraging that as much as possible. The kid knows Pines of Rome inside and out. We've been listening to some of your recommendations in that thread, particularly Britten's Young Person's Guide to the Orchestra.