S-1 NrT's or S-2 ?!

[theophile]

Amazing comparison snaabster (http://forum.ascendacoustics.com/showthread.php?6024-Sierra-2-Review-%28vs-B-amp-W-803D%29&p=51686#post51686)! I'm sure the B&W 803D's are no slouch (better not be for $10K)! But, to effectively hear the Sierra 2's as being equal or even better is a wonderful tribute to the efforts of Dave, Ascend, RAAL and Seas!!!

I'm not a newbie to Music, Audio or a wonderful listening experience (live or recorded). However, it's been quite a few years that I delved into new audio systems (speakers and electronics) and a lot has changed in the industry (or so it seems). As I recently retired, now have the time (not necessarily $$$) to re-energize my love for music (thanks to my Grandmother who taught me and over 400 other students classical piano over a 55 year span of music education)!

My background: I have formal training in classical piano (10 years) and a BA degree in instrumental education. I taught instrumental music for a few years and have attended many "acoustical concerts" in the past 30+. During the 80's, my tested hearing showed that 75% of my frequency sensitivities were at or below 0db (especially from 1,000 to 18,000hz). Today (40+ yrs later), I still test at the thresh-hold of the equipment (0db) to 10db (thanks mom). SHMBO understands I have "selective hearing"...can't hide or lie! On 2-C Stereo, In the 80's I purchased ADS 1290 Series II studio monitors w\bia-amped PA-1 modules installed. Sounds were very open, detailed and powerful, with a soundstage that jumped out into the room and beyond the wall interiors...Very Nice. Started with vinyl, but moved to CD in 1982 (NAD). I visited many audio salons and heard some very expensive and unbelievable 2 channel stereo systems. I know what acoustical piano, jazz, vocals, BB, symphonic and R&B sounds like Live and wanted those sounds in my listening room presentation...but with 4 children, family became priority for the next 35 years!

Just finally had the opportunity to set-up my 9ft x 10ft dedicated near field 2-channel intimate "Music Room" in our home! With Dave's patient professional set-up advice, I paired new Sierra 1 NrT's (stored since 2011) with Emotiva Pre-USP1, Power-UPA2, Sub-Axiom EP500 and an oldie but goodie Player-Phillips Reference CD880.

I now have the Sierra's 6ft apart (8in. away from the 9ft setup wall) and about 8ft from my listening position (.75 ratio-see pic). Due to the near field listening position, I have no toe-in of the Sierras. The small room size with entry and furniture restrictions doesn't allow me much lead way in opening the speakers up or relocating the electronics and sub, sigh...oh well. These past 2 weeks has been a long process and follow up listening sessions to equipment and speaker arrangements, cleaning up equipment boxes, removing a large exterior cabinet enclosure, stabilizing the Sierra stands, trying different interconnects\speaker wires, testing sound with old Sony receiver (vs Emotiva Separates=Big Improvement) and even discovering that the 28 yr old Philips CD player sounds better than the new Emotiva ERC-2 CD player (now going to oldest son)!

HOWEVER, this current and swift journey into audio bliss has been rewarding and worth it! I'm now at 100% satisfaction with the Glorious Sounds coming forth from the Sierra NrT's!!! :) Wow, Wow...I'm rediscovering my instrumental and vocal CD libraries with stunning R&B, Jazz, Acapella, Big Band and Orchestral recordings! Soundstage precision, air and dimentionality extends well beyond my 9ft listening wall confinement, both with lateral accuracy and hall\studio ambient depth! Attacks, delays, harmonics, overtones, character, tonalities and timbre are all very realistic and alive in instrumentals, vocals and percussion. It seems there is no audible end to the liquid, smooth and very open top end, the midrange clarity, resonances and resolve, and now, the articulate, natural and quick upper and lower bass (w\o sub)! Overall, superlative descriptions such as Engaging, Emotional, Live, Real and of course, Fidelity all come to mind (and Ears)! I do have some bad recordings, but the great stuff is jaw dropping and mind blowing! It's the Best I've ever heard from any of my recordings, my previous stereo, or any I've Experienced before in audio specialty\salon stores (likes of B&W, Rogers, Spendor, Paradigm, Vandersteen, etc...)...Period!!! :cool:

Other than on-site live music performances, It's difficult to imagine any listening room sound reproduction being much better! But, I've read about and learned much concerning the Sierra 2's, their design work and ultimate successes hear (pun intended)! I'm certainly not ready to throw my Sierra 1's out (just yet), but as I told Dave, would love one day to put my S-1's side by side with the new S-2's to hear, in my listening room, the possible extra realism in my recordings that till now, I don't seem to be missing!? As I've stated my new findings and appreciation for the above NrT's in my intimate music room and with my current electronics, I'm very satisfied with the Sierra 1-NrTs!

One day I just may have to get the Sierra-2's here and ultimately "Hear" what all the S-2 fuse is about! :D

Ted

[Crk140]

For rock i love the sierra 1 nrt. I could not imagine a better speaker. The speakers disappear. It sounds like the band is in my room.

[Bruce Watson]

Just finally had the opportunity to set-up my 9ft x 10ft dedicated near field 2-channel intimate "Music Room" in our home!

The math makes me think that a 9x10x8 (I'm guessing about ceiling height since you didn't specify) room should have a heck of a room mode problem. Have you done any room treatments to control standing waves, or control reflections? Room treatments may well be as important as the speaker in small rooms. Heck, even large rooms.

If you haven't treated the room, that may well give you a bigger improvement in sound quality than the difference between an S-1NrT and an S-2. A well treated room will make it easier to hear the difference.

[theophile]

For rock i love the sierra 1 nrt. I could not imagine a better speaker. The speakers disappear. It sounds like the band is in my room.

Crk140...Welcome to AA!

I'm not a rocker, but in "my room", the Sierra-1 NRT's certainly do disappear. Orchestral, jazz, R&B, BB, choirs and vocals (that are well recorded) Do disappear into what I hear as a "3D" wall of ambience and stage depth, with balanced and realistic "live" as-if-you're-there sound presentation that defies all "2-channel Stereo" logic! :confused:

In other words, What I See (electronics-speakers-small room) and What I Hear (live acoustical music in it's recorded venue) is kind of mind-blowing if you will. In my personal experiences, when you have Live acoustical (non-amplified) references of various musical performances, you become aware of minuscule auditory ques that lets you differentiate a "recording" from "live"! When an audio 2-channel set-up makes you -Believe You Are There-...well, many things in your listening environment are done right (recording-electronics-speakers-room acoustics, etc.).

In this case I agree, the Sierra-1 NRT's, Do It Right! :cool:

Ted

[theophile]

The math makes me think that a 9x10x8 (I'm guessing about ceiling height since you didn't specify) room should have a heck of a room mode problem. Have you done any room treatments to control standing waves, or control reflections? Room treatments may well be as important as the speaker in small rooms. Heck, even large rooms.

If you haven't treated the room, that may well give you a bigger improvement in sound quality than the difference between an S-1NrT and an S-2. A well treated room will make it easier to hear the difference.

Hi Bruce,

Thanks for your suggestions and input. My music listening room is a small spare bedroom, 9'w x 10'd x 11'h (90sf floor space - 990cf total).

The only room treatments are the stereo electronics\sub\monitors on the listening wall (see pic post #1), wall furnishings on other 3 sides (30sf of framed oils), 2 large draped french doors to the left, 2 large closet raised panel doors on the right and a love seat listening soft pillow couch on the far end, floor carpeted throughout!

Overall, I'd consider my room dead. Overall response sounds equal anywhere, especially at my 2 listening positions. I do not hear any room nulls\peaks, or standing waves or unwanted reflections. Top to bottom balance is smooth, equal and very expansive as the soudstage imaging can go 5-10ft beyond my side interior walls and the recording venue ambiance 20 to 30ft behind the listening wall...HUGE (of course, dependent on recordings)...The S-1 NrT's just Disappear!

With my current listening room dynamics (equipment, furnishings, dimensions), not sure any additional "treatments" would improve the wonderful intimate near-field type listening venue that I currently have. In my audio\music\education\experience background, I feel it is about as good as it's going to get...for This Room! To date, it is my only option for a dedicated music playback environment...believe I have it about as good as it is capable of (or very close to)!

Could be a little better, possibly yes...but at what cost and trouble!?? Anyway, Still enjoying the S-1 NrT's!! :o

Ted

[theophile]

It's been over 2 years since I settled in with my S1 NrT's. Been enjoying a wide genre of 2.1 music, especially acoustical small ensembles, solo and acapella vocals and a mix or R&B and jazz! I already know my environment quickly became my most critical weakness in this journey, but have done pretty well in achieving a life like replication of my greatest recordings.

For the past 42 years, a good friend and I have delved into higher-end recorded music, realistic stereo sound reproduction and electronic\speaker building. We've leaned a lot, listened to and experienced some Great sounds and had many successes (and failures) as to attempting to recreate an emotional "live Venue Experience" in the confines of our humbled Listening Rooms! A few weeks ago, loaded up my S1 NrT's and stands, then trekked 900 miles away to enjoy a speaker\recording blow out in his well balanced and natural sounding dedicated\open 2-channel listening room (16'X26' basement, 8ft acoustical ceiling, wood floors and furniture sound treatments). Speaker stand placements were out 2' from the rear 27' wall, with around 13' of separation and center equilateral listening positions on the opposing long wall. We used a mix of superb CD's and high-end digital recordings. His well designed and beautifully built 2-way monitors (Adelphos designed by Jeff Bagby, using high-end SB Acoustic drivers) and other kit speaker systems were all thrown in the mix for a blow-out week of musical bliss!! For 75% of all listening, the satellites were crossed over @ 80hz with low pass being handled by a newly refirbed Paradigm sub. The other 25% of the time was full range playback of each system.

Through the many hours of day and night intense speaker auditions, music and recording evaluations and room placement\experimentation, it became very obvious to me the contribution the wonderful listening environment imparted on my Sierra 1 Nrt's! They obtained a level of realism, clarity and disappearance that I'd not heard before in my small 90sf listening room...these babies Really Sang beautifully in his larger, much better acoustic listening room...Amazing! More details, better definition, better balance top to bottom and a greater sense of "out-of-the-box" sound staging were all there with any of my favorite 24 CD's I had brought!! His Adelphos were very impressive, especially how close they performed to the S1 NrT's. It's hard to imagine overall better 2-channel sound reproduction from the S2's (especially the S2Di's), but his "listening environment" Topped any and all reproduction environments (treated audio salon rooms, high-end audio stores, quality home environments) that I've ever experienced in my past 42 years! No doubt, the S2's or the S2Di's would have had us constantly picking up our jaws off the floor! :rolleyes:

Over the week, we enjoyed other hobby activities and were able to catch up and reminisce about life and how we got to where we are. The visit was an eye opener for me and once home, had the NrT's reset-up in my small intimate environment on a "new twist". Half of my past listening sessions were enjoyed with the NrT's full range (sub turned off). My Pre-amp control requires switching RCA cables to go from full range to high pass, so just left the NrT's FR. Depending on the music, I always enjoyed this arrangement, so never took the initiative to try the LP+HP separation. After this trip, I was Finally resolved to listen with the NrT's not full range, but HP crossed over around 70hz, with the very musical Axiom EP500 LP @70hz (not the 50hz I had before).

WOW!!! My ignorance and stubbornness has robbed me of some Superb musical enjoyment these past years! I now come to realize that most of my known stereo issues have been my lack of a better set up in my room integration. Removing the full range challenges to the S1 NrT's has created a greater listening experience than I ever had before...more dynamics, greater definition and detail, improved clarity and an even more accurate sound stage, with higher precision pin-point width and depth placements!! Bass is tighter, smoother and better integrated, midrange is more open and clear and the tweeter smoothness and detail has soared! Overall, there is a more Cohesive, Realistic and Live emotional involvement with any genre I listen to...what an Amazing Revelation (should have just listened to Dave & Mike)!!!

Sorry for the long winded post...wanted to share for anyone that might benefit from my "mistakes"!

Ted

[davef]

Thanks so much for the update Ted, yes -- relieving a speaker of having to reproduce deep bass is extremely beneficial to overall sound quality and dynamics.

[theophile]

Thanks so much for the update Ted, yes -- relieving a speaker of having to reproduce deep bass is extremely beneficial to overall sound quality and dynamics.

Thank YOU Dave!! :D

A little late response, but these past 2 months I've been busy thoroughly enjoying the added details and realism in my new found "high pass" stereo environment...ahhhhh! :D

Thought I'd post another new found revelation, one that I'm sure was adaptable to the unique and limited listening room environment I have. HERE (http://forum.ascendacoustics.com/showthread.php?6845-Speaker-Positioning-(toe-in)&p=60379#post60379) is a reference to the post (with pics) I created concerning "Toe-in" (or lack thereof)! Possibly, fancy room equalization or room acoustical treatments would have obtained what I have now??

The S2Di are tempting, but its difficult to imagine (in-my-room) a further expansion of 2.1 playback clarity, realism, holographic presentation and 3D aural bliss...especially at 5X the investment! I'd have to "hear" the S2Di's in MY near-field environment to see how they might transcend the room limitations as in the end, that would be their greatest challenge!

However, I certainly understand AA policies. One day, may just have to hop a jet to Cal. and have a demo session between the S1 NrT's and S2Di's!!! :confused: :rolleyes: :cool:

Ted

[jimb]

With good SUB support, S2 (RAAL) or even Luna (RAAL) should be a nice improvement over S1-NrT, no? 30 days in-home trial, no? 15% off of new S2s right now!

[theophile]

With good SUB support, S2 (RAAL) or even Luna (RAAL) should be a nice improvement over S1-NrT, no? 30 days in-home trial, no? 15% off of new S2s right now!

Hi Jim,

You're S2\Luna suggestion is great, thanks for your input. But, already been there...done that! :o

Two years ago, received the S2's (B-stock-Piano Black-Gorgeous) from Dave and had many listening sessions in direct comparison to the S1-Nrt's! Before the end of the 30 day trial period, sent them back to Ascend. In a larger room environment, I have No Doubt and know the S2's would be a step up from the S1 NrT's! They are Extremely accurate and natural on the top end (RAAL) and the midrange\bottom end is equally natural and accurate (curvy mid-woofer)...just a Superb Engineered High End Monitor!!

However, in my small near-field listening room, I just could not get past their Vertical Dispersion limitations. Although the room is small (90sf), the ceiling is high (11ft) and felt they never energized that extra open space. I had about a 1" -full range- comfort zone in the very wide horizontal sweet spot area to adjust my ears up and down (on 31" stands w\S2's tilled forward 5-7 degrees). Once locked in, the presentation was Glorious, Holographic and and 3D! However, as soon as I started to stand, the top 2 octaves of the music rolled off 4 to 5 db, leaving to my ears, a veiled and compressed nasal midrange. To me, this dispersion characteristic would be a non-issue given a little larger listening environment (as most owners appear to have)!

The NrT's have near as much equal horizontal dispersion as the RAAL's, but being a dome, present that wide dispersion characteristic equally in vertical dispersion! For me, my genre of music, my equipment and in my listening room, felt the S1 NrT's present a more realistic and live musical experience!!

IMHO, to Really top the current sound I have in my listening room, I'll experiment with #1-room\wall treatments...#2-Investing in the S2Di's!!! ;)

Ted

[jimb]

Thanks for sharing that experience.

[Asliang]

Hi Jim,

You're S2\Luna suggestion is great, thanks for your input. But, already been there...done that! :o

Two years ago, received the S2's (B-stock-Piano Black-Gorgeous) from Dave and had many listening sessions in direct comparison to the S1-Nrt's! Before the end of the 30 day trial period, sent them back to Ascend. In a larger room environment, I have No Doubt and know the S2's would be a step up from the S1 NrT's! They are Extremely accurate and natural on the top end (RAAL) and the midrange\bottom end is equally natural and accurate (curvy mid-woofer)...just a Superb Engineered High End Monitor!!

However, in my small near-field listening room, I just could not get past their Vertical Dispersion limitations. Although the room is small (90sf), the ceiling is high (11ft) and felt they never energized that extra open space. I had about a 1" -full range- comfort zone in the very wide horizontal sweet spot area to adjust my ears up and down (on 31" stands w\S2's tilled forward 5-7 degrees). Once locked in, the presentation was Glorious! As soon as I started to stand, top 2 octaves of the music rolled off 10 to 20 db, leaving a veiled and compressed nasal midrange.

The NrT's have near as much equal horizontal dispersion as the RAAL's, but being a dome, present that wide dispersion characteristic equally in vertical dispersion! For me, my genre of music, my equipment and in my listening room, felt the S1 NrT's present a more realistic and live musical experience!!

IMHO, to Really top the current sound I have in my listening room, I'll experiment with #1-room\wall treatments...#2-Investing in the S2Di's!!! ;)

Ted

I wonder if Ascend would consider selling the foam pads with the RAAL 70-10. From what I've seen on DIY Audio people have measured the 70-10 with the foam pads and it seems to improve the vertical dispersion significantly.

https://www.madisoundspeakerstore.com/ribbon-tweeters/raal-70-10d-raal-ribbon-tweeter-with-amorphous-core/

[davef]

I wonder if Ascend would consider selling the foam pads with the RAAL 70-10. From what I've seen on DIY Audio people have measured the 70-10 with the foam pads and it seems to improve the vertical dispersion significantly.

https://www.madisoundspeakerstore.com/ribbon-tweeters/raal-70-10d-raal-ribbon-tweeter-with-amorphous-core/

That's an entirely different tweeter, with a longer ribbon diaphragm. Even with those pads mounted on the 70-10, the ribbon in the S2 - with a shorter ribbon, has wider vertical dispersion. Those pads are not appropriate for the S2 tweeter. In the 70-10, those pads work by absorbing sound, effectively shortening the ribbon diaphragm.

Based on Ted's comments, unless he was listening at about 3 feet away, which is possible, the difference in height between him sitting and standing would in no way account for 10-20dB loss in the upper octaves. It just doesn't work that way and I suspect those numbers are just a guess on his part, considering he stated 10-20 dB, whereas that would be equivalent in saying well I might have been going 10 mph or maybe 100 mph.

More than likely it was a few dB's -- due mostly in part to the differences in the overall frequency response between the S2 and S1NrT, with only a fractional part of what he heard due to the slightly more vertically directional response of the S2 tweeter.

By design, the Sierra-1 NrT has a rising high frequency response, while the S2 does not (it is extremely neutral). The S1 NrT will produce significantly more high frequency energy. Considering his high ceilings which reduce ceiling reflections (thus reducing room ambience), this results in more overall high frequency losses in a room, making it simple to understand why - for Ted's ears, he preferred the S1 NrT.

[theophile]

Dave,

Thanks for clarifying the AA custom tweeter difference in the S2 with the 70-10 base RAAL's!

When standing, there was a definite drop in vertical dispersion energy response in the S2's from my 87" sitting position, but my prior 10-20db loss statement was exaggerated...probably more like 4-5db. With the S1 NrT +4 db rise from 7Kh to 14Kh, believe your summation on why I prefer the NrT's in my high ceiling listening room makes perfect sense.

My last audio-metric hearing test (2015) proved I still hear 10Kh at a 0db reference levels...feel very sensitive to any loss or gains in that extreme near ultrasonic region. For me and my environment, the S1 NrT's soundstage and realism still recreate an Amazing and Live 2-channel experience!! :o

Ted

[davef]

Dave,

Thanks for clarifying the AA custom tweeter difference in the S2 with the 70-10 base RAAL's!

When standing, there was a definite drop in vertical dispersion energy response in the S2's from my 87" sitting position, but my prior 10-20db loss statement was exaggerated...probably more like 4-5db. With the S1 NrT +4 db rise from 7Kh to 14Kh, believe your summation on why I prefer the NrT's in my high ceiling listening room makes perfect sense.

My last audio-metric hearing test (2015) proved I still hear 10Kh at a 0db reference levels...feel very sensitive to any loss or gains in that extreme near ultrasonic region. For me and my environment, the S1 NrT's soundstage and realism still recreate an Amazing and Live 2-channel experience!! :o

Ted

Hi Ted,

The 1-2 foot difference in height at 7 feet distance would only account for a slight upper frequency loss above 10kHz due to the vertical directivity of the ribbon. I suspect what you are hearing is actually due to the higher crossover point in the S2 vs the NrT, which would account for a mild high frequency dropoff from the woofer near the crossover point. This is common with any speaker but with the NrT, we are able to use a very shallow tweeter rolloff and a low crossover point.

I absolutely do not doubt what you heard, but I don't believe it is at the frequencies you thought it was at, nor what caused it...

[jimb]

Guess you just need that S2-xrS: S2 with RAAL 70-20xr and Special SEAS mid-woofer!

[theophile]

Hi Ted,

The 1-2 foot difference in height at 7 feet distance would only account for a slight upper frequency loss above 10kHz due to the vertical directivity of the ribbon. I suspect what you are hearing is actually due to the higher crossover point in the S2 vs the NrT, which would account for a mild high frequency dropoff from the woofer near the crossover point. This is common with any speaker but with the NrT, we are able to use a very shallow tweeter rolloff and a low crossover point.

I absolutely do not doubt what you heard, but I don't believe it is at the frequencies you thought it was at, nor what caused it...

Dave,

What is the crossover point\slope with the S1 NrT's (had them since 2011, never knew)?

If\When AA and Seas conclude that the new S2Di woofer could be a viable stocked upgrade component for past Sierra owners, would the possibility of dropping-in, or integrating it with the S1 NrT's work out and improve bass and midrange from what I already have??? :confused:

As always, appreciate your time and assistance! :)

Ted

[davef]

Dave,

What is the crossover point\slope with the S1 NrT's (had them since 2011, never knew)?

If\When AA and Seas conclude that the new S2Di woofer could be a viable stocked upgrade component for past Sierra owners, would the possibility of dropping-in, or integrating it with the S1 NrT's work out and improve bass and midrange from what I already have??? :confused:

As always, appreciate your time and assistance! :)

Ted

Crossover point on your S-1 NrT is ~1.8 kHz. The custom S2Di woofer is technically quite superior to the woofer in your Sierra-1 NrT's. Bass would be tighter, more accurate with improved transient reproduction but overall extension would be about the same, maybe just a tad bit lower. The major improvements would in the mids, but again - this is from a purely objective stance, technical improvements don't always lead to subjective improvements, especially in audio.

[theophile]

Crossover point on your S-1 NrT is ~1.8 kHz. The custom S2Di woofer is technically quite superior to the woofer in your Sierra-1 NrT's. Bass would be tighter, more accurate with improved transient reproduction but overall extension would be about the same, maybe just a tad bit lower. The major improvements would in the mids, but again - this is from a purely objective stance, technical improvements don't always lead to subjective improvements, especially in audio.

Thanks Dave,

Sorry for the late response...just returned from Vermont and Montreal...burrrrr, but gorgeous scenery! :)

Soooo, would the S2Di custom woofers be a "drop-in" S1 NrT fit (same xover, same cabinet, same porting), or would I need to send them in for an upgrade face-lift\resert?!?

Ted

[Mag_Neato]

Thanks Dave,

Sorry for the late response...just returned from Vermont and Montreal...burrrrr, but gorgeous scenery! :)

Soooo, would the S2Di custom woofers be a "drop-in" S1 NrT fit (same xover, same cabinet, same porting), or would I need to send them in for an upgrade face-lift\resert?!?

Ted

I'd expect a new crossover as well. Cabinet/porting should remain the same.

Bear in mind, that new woofer is strictly custom hand built at this point for the Diamond tweeter Sierra on a per-order basis as far as I know. Dave is trying to work with SEAS towards a larger volume production version that would significantly reduce cost, but he still thinks it would cost $300 just for the woofer.

All of the Sierra upgrades have been drop-in and easily done by the end user.

[theophile]

I'd expect a new crossover as well. Cabinet/porting should remain the same.

Bear in mind, that new woofer is strictly custom hand built at this point for the Diamond tweeter Sierra on a per-order basis as far as I know. Dave is trying to work with SEAS towards a larger volume production version that would significantly reduce cost, but he still thinks it would cost $300 just for the woofer.

All of the Sierra upgrades have been drop-in and easily done by the end user.

Thanks Ed,

Been following the possible new woofer availability info. If the upgrade benefit would be a simple drop-in for the NrT cabinet, I'm Definitely Interested!!

Love what I have, but for the upgrade cost, believe the SrT's could become the monitors of my dreams!!:D

Ted

[davef]

Thanks Dave,

Sorry for the late response...just returned from Vermont and Montreal...burrrrr, but gorgeous scenery! :)

Soooo, would the S2Di custom woofers be a "drop-in" S1 NrT fit (same xover, same cabinet, same porting), or would I need to send them in for an upgrade face-lift\resert?!?

Ted

For any high performance speaker, when you change to a different driver, a new crossover would be required to optimize performance.

[theophile]

For any high performance speaker, when you change to a different driver, a new crossover would be required to optimize performance.

Thanks Dave...will continue to follow the S2Di woofer development! :cool:

Ted