In search of my last great loudspeaker

Rodney Gold said:

Wow.. you have endless perseverance.
Why are you not using DSP with these?

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marty said:

(...) Now, back to the woofers-those wonderful Gotham v2 woofers whose integration with the S2s are currently the bane of my existence. There are basically two ways to set up the woofers. The first is the run the S2s full range and then bring in the Gotham using their own internal crossover, phase adjustment and gain. This the way I have helped set up Brian and Steve’s system. The idea is to let the S2s do most of the work, and bring the subs in very low (30-40 Hz) so that on most material, you don’t even hear the subs. But when the music calls for it, the subs fill out the bottom end most satisfactorily. The second way to add the subs is to use the formidable JL crossover that I have written about previously.

http://www.whatsbestforum.com/showt...T-digital-crossover&highlight=spectral+jersey

That’s the method I am currently exploring and it’s a work in progress. Remember, the Gotham’s are first set-up by using their auto EQ so the woofers are dsp’d below 100Hz. It is their fabulous dsp program that is what makes their use so attractive. You can talk to me about the merits of not using dsp until you are blue in the face, but in my experience, there is no substitute for the sort sonic benefits one can obtain with good EQ of the bass frequencies, and the Gotham’s dsp paradigm is outstanding in that regard. That does not mean I am using the subs up to 100 Hz. Rather I have the luxury of adjusting the crossover point (currently 42 Hz) and slope considerably and further work is necessary to extract maximum performance from the system.

All told, I am generally pleased with the limited work I have done to date to integrate the Gothams v2’s and the S2s to achieve a system with genuine low bass capability in addition to excellent performance in the rest of the frequency range. But I think I have considerably more work to do before achieving my final set-up. Stay tuned.

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bonzo75 said:

I too am betting Marty will go back to DSP eventually

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andromedaaudio said:

S 2. ?
Which speaker are we talking about isnt the name Alexandria X 2. (...)

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bonzo75 said:

I too am betting Marty will go back to DSP eventually

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andromedaaudio said:

Another option would be give the ambient tw at the back a bit more out put and the focal a bit less , just thinking out loud lol , they are both resistor controlled right ?
IIRC the ambient tw is either a softdome or a ringradiator softdome so the focal was there for a reason , wilson built his rep . partly with that focal so it cant be that bad
Speaker placement is off course very imporant

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ack said:

So one thing is clear Marty, you like adjustable speakers. So I'd guess you are buying a used mega Wilson. Great information you posted!

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marty said:

This isn’t quite the update that I was planning on, but it describes ample work therefore it is reasonable to report at this time. The big mystery is no longer a secret. The basic speaker that I chose to begin my “ultimate” project is the venerable Wilson Alexandria S2. Before describing the initial goal of the project, let me begin by saying what I found to be some attractive properties of the S2 that led to its selection as the center piece of my loudspeaker project. Actually, those attributes are not hard to understand as the S2 has numerous sonic strengths that have been well-described elsewhere. At its heart, the S2 is a superb sounding speaker with good full range frequency response, excellent dynamics, low distortion, relatively high efficiency and above all, a highly musical signature. It can also handle both "big" and "small" music with equal aplomb. Music sounds like music when the speaker is “on”, and by that, I mean set-up properly; a subject we shall discuss in some detail shortly. In addition, it offers what can only be described an insanely tremendous value on the used speaker market. This is a 165K speaker that can now be purchased in outstanding condition for about 50K. That’s the sort of hand-me-down I’ll take in a heartbeat.

Sure, there are many outstanding alternative SOA loudspeakers I could have considered, and without listing all of them, all I will say is that many of those were simply beyond my means. In some cases, there were fatal flaws in specific models that disqualified a speaker from consideration. The decision to pull the trigger on the Wilson’s was also facilitated by the fact that I had great familiarity with them. Two Alexandria S2 systems provided most of my intimate listening experience. These were Brian Flower’s excellent solid state (Boulder) system in Dallas and Steve Williams’ venerable and outstanding tube-based system (LAMM) in California. But critical to hearing the S2s in their homes, I also had the privilege of helping each of these owners dial-in a pair of JL Audio subs in their respective homes, which taught me a great deal and provided good experience for my current undertaking. For all its strengths, the S2 also has some limitations, and aside for a wife acceptance factor that on a 1-10 scale actually scores negative numbers (“what the hell is that? It looks like Megatron. Get it the hell out of here”. Gee, thanks, honey), one of the limitations that is clear is that the S2 simply is not a full range speaker. I don’t care how its set up or where it’s set up. I’ve heard them in enough settings to state this unequivocally. It simply does not have much bass below 30 Hz in any room I have heard them. And so, my plan all along was to supplement the bottom end with my JL Gotham v2s. However, my experience also led me to believe that the top end of the speaker may also have some limitations imposed by the famous Focal inverted beryllium dome tweeter. Thus, my intention was to set up the S2s, blend in the Gothams flawlessly, and then attack the speaker’s top end by replacing the stock tweeters with the Wilson Convergent Synergy soft dome tweeters that are now standard issue on the Alexx, XLFs, and other newer speakers in the Wilson line. Perhaps now, dear reader, you will forgive me for not reporting the results of my efforts previously as this is no plug and play project.

Let’s take things in relative order. The exercise began with the simply task of trying to set the speaker up in my room as best as possible without any subwoofer or tweeter embellishments. When I received the speakers in mid-October, I asked myself “how hard can this be?” and was arrogant enough to think it would be a relatively easy task. After all, Wilson’s set –up instructions were clear so easy peasy, right? Hardly. Let me share at this point that I have owned and set up some speakers in my time that are generally considered to be amongst the most difficult ever to set-up. I’m thinking mostly Maggies, and Martin Logan CLS’s. But the more I dove into the world of S2’s, the more I wanted to reach for the Prozac. In fact, it took me a good 2 months before I was convinced that they would be keepers- that’s how tormented I was in setting these things up? Why?

In understanding my frustration with set-up, the reader should recall that for many years, I had a dsp-based system and most of you know that my mantra has always been “frequency response- frequency response-frequency response” If that isn’t right, you might as well go home and certainly, under no conditions, would I want a complicated project to advance if I couldn’t get the fundamental frequency response “right”. In this case, “right” means something that approaches what I consider to be a sonically desirable frequency response at the listening position, which for me, is the B&K microphone curve mentioned many times in my writings.

http://www.whatsbestforum.com/showthread.php?520-DSP-one-person-s-experience&highlight=tact

I realized that without dsp, this might not be an easy task because the truth is that without dsp, it would be sheer serendipity if I hit that B&K curve spot on. I therefore realized I might have to lower my sights, and accept the fact that I would have to be content if I obtained a relatively reasonable facsimile of the B&K curve that didn’t have excessive peaks or valleys (>6 dB in the critical room boundary region of 400Hz and below), yet sounded good. Let me tell you, getting there was a bitch and a half.

To condense a few hundred hours of work into a sentence, I spent a long time moving those fkn behemoths within a 1 ft. square footprint a ¼” at a time, until I achieved what I considered to be the best response I could obtain. To be honest, for the first month or so, I had dreams of taking the speakers to the garage and chopping then up into firewood with an axe just to make me feel better. Just in case you are wondering, the way the move these is not to move them on casters and then spike them as Wilson suggests, as doing that repeatedly would institutionalize the sanest of individuals. Rather, once on spikes, get some sliding silicone pads and place upon them a small brass plate containing a dimple for the spikes, which makes moving them rather quick and effortless. A basic move from one spot to another takes about 10-15 minutes without fine leveling. Leveling, as it turns out, is one of the greatest secrets to obtaining maximum performance from the S2s.

I learned this the hard way. Move after small move for weeks had failed to give me satisfactory bass performance in a speaker whose very strength is indeed bass/upper bass performance. I was exasperated trying to coax good bass out of the speakers until I learned that the rake angle of the speaker is critical to its performance. I must give credit forth this revelation to Sunil Merchant at Sunny Components in West Covina, CA, an authorized Wilson dealer from who I learned the “trick”. Sunil insisted it was not good enough put a bubble level on the top of the woofer cabinet to assure the top of the bass cabinet was parallel to the floor. Rather, he insisted one must use a digital level where one can measure displacements from level in increments as small as 0.1 degrees. When he told me this, I thought he was nuts. Surely my bubble level was able to show me what “level” looked like? But that was not his point. Rather, he said, the sound of the speaker will change dramatically with raising front by as little as 0.1 degrees from true level and you need a digital level to make those adjustments reproducibly. Never make an adjustment he said, that was more than 0.1 or 0.2 degrees at one time, as the resultant sound is that sensitive to rake angle. When its right, you’ll know, he said. Sure enough, I worked on each side independently and found, much to my amazement, that the difference of 0.1 degrees made a substantial change. In addition, Sunil said, adjustments that cause the speaker to lean to the inside by equally small increments of 0.1 degrees could also be used to coax the best sound from the S2s. The small change I made in rake angle using the digital level (Husky, 10”) was the key that changed my mind of what the speakers were capable of sounding like in my room.

The obvious explanation for why the rake angle of the woofer cabinet is seemingly so critical is that the speakers hover on the edge of inducing floor bounce with its commensurate degradation in frequency response (generally suck-out in the 125-180 Hz region) in their current configuration which uses a woofer cabinet whose front is perfectly perpendicular to the floor. Tilting the cabinet back a fraction of a degree therefore has a significant benefit that seems to me to be larger than one might expect with such a small change. It should be noted that the latest current Wilson speakers, namely the Alexx and the WAMM, employ woofer cabinets that are significantly raked back from perpendicular. No doubt Dave and Daryl Wilson were aware of the potential floor bounce issues of the previous S2 (and XLF) design and have modified the bass cabinet accordingly (this resulting in better bass performance from what I have read).

And now for a small digression. You may recall that some time ago, these pages were filled with pages upon pages of testimonials of how much better some big Wilsons sounded in some owner’s system (while others did not experience a benefit), when switching from the factory supplied spikes, to the popular Stillpoint (Ultra 5/6) footers. Based on what I learned regarding the changes in sound that I was able to obtain with minute changes in rake angle, I have to wonder if the changes many noticed and assumed to be due to the difference between the spikes and Stillpoints, might just possibly due to minute changes in rake angle that occurred when making these changes? I’m just sayin’…..

The level of adjustment that is necessary to obtaining great sound from the S2s, is not only dependent on the correct rake angle and placement of the woofer cabinet, but on finding the optimum alignment of the upper 3 modules (two midrange units and a tweeter). This is a hard-enough task in a speaker system employing multiple drivers. But in the majority of other speakers, the drivers are locked in relative position to each other in their cabinet and the electronic crossover design is key in establishing the final voicing of the speaker at the listening position. This is also true in part with the S2s. However, Wilson’s design is very unique and adds considerable complexity because of his use of what he calls “aspheric group delay”. In this configuration, the alignment of the midrange and tweeter units with respect to each other change is a function of the distance of the speaker from the listener and height of the speaker’s ears from the floor. It’s basically an array of speakers that are aimed much like a lens to place the blended sound precisely with respect to the listener. What impressed me greatly, is not only the design of this approach (it is the very key to “time alignment” that is taken to its ultimate expression in the WAMM Chronosonic), but the marvelous and painstaking engineering that allows for excellent alignment of the drivers for any listener at any reasonable distance and seating position as guided by several graphs and nomogram tables found in the user manual.

As beautiful a system as it is when set up correctly, I believe there is one “concern” and one “corollary” that should be mentioned. The first is an easy one- the corollary. As good as these speakers can sound when set up correctly, they are also equally capable of sounding quite unimpressive if the alignment to the listener is not achieved satisfactorily. Let’s think about that for a moment. How many times have we heard some listeners say they “never heard a good pair of Wilson’s?” How many times are show reports less than glowing for the big Wilsons? Well, now that I understand the reason for these observations. Unfortunately, the incredible precise positioning of the drivers mandate that they are correctly aligned for one, and only one, distance and listening height. Therefore, it should come as no surprise that the listening experience of any listener may be less than impressive if the driver alignment for that listener is less than ideal. In fact, the next time you go to hear these, ask who they were set up for and based on that person’s ear height from the floor, you should try sitting accordingly in the listening chair. Simply stated, I know of no other speaker that can sound so remarkably different to two people, especially if the disparity in their ear height to the floor exceeds 1 inch. One listener may think they’re in heaven, while the other may shrug his shoulder totally nonplussed. Yes, set-up is that critical. When it’s good, it’s very good, and when it’s not, it can be very disappointing. That’s just the way it is. If you want omni-directional, look elsewhere. Horizontal forgiveness by the way, is somewhat better in this regard. They are the exact antithesis of my Pipedreams or any line array system, which have much better vertical latitude for listening than horizontal latitude. To quote my audio mentor, the late Paul Heath, “you pays yer money and you takes yer choice.”

Let’s get back to the “concern”. It is namely this. Even Wilson says that the setting in his meticulous graphs and tables are meant to be used only as guide and that the final position of the drivers should be determined by listening. OK, that sounds great, but how the hell do you make increment adjustment in each speaker module (each set individually in their own ingenious track alignment system) without a good degree of confusion and experimentation since you have to listen to all the drivers at once but want to change only one at a time? One tool that helped me do this was rather easy and effective. I simply covered 2 of the 3 modules with a towel which allowed me to optimize the alignment of any one module at a time. It took me two months to learn that trick but the results were well worth it. I would adjust one module, listen and then uncover the other 2 and listen again. Trial and error revealed my final settings to be close, but not identical to Wilson’s initial recommendations.

So, at this point, what I have is an acceptable set-up of the speakers in the room by themselves, without any subwoofers. Let’s kill the suspense about the tweeters right now to get it out of the way. My set-up and listening of the speakers to date has changed my assessment of the Focal tweeter in the S2s. They turn out to be a lot better than I thought initially, and in retrospect, I think that was because that the systems in which I heard them were not set-up specifically for me. I will reiterate that if the upper drivers are not set up precisely for a given listener, the sound can be disappointing and the tweeters can sound a bit bright. When set up correctly, they are indeed very neutral and sonically delightful. It is true that the tweeters do not have the dispersion width of some other tweeters that are available, but honestly, that does no interest me much since I listen almost exclusively in the hot seat and couldn’t care less what they sound like 40 degrees off axis. Dave Wilson himself has said that while the tweeter is excellent, it can get a little brittle when driving it hard and I would agree, but it is a minor fault and one that I am not eager to remedy anytime soon with my planned replacement using the Convergent synergy tweeters. The bottom line is that when set up correctly, the tweeters are musically compelling, period. Hence, the tweeter project is on the back burner for now. Before we leave the tweeter issue, let me address what will surely be a common question which is, is it possible to use the Convergent tweeter in the S2 in lieu of the Focal tweeter? The answer, in my humble opinion is yes. I will also share with you that Wilson says it cannot be done. That is a discussion for another day. I have researched this quite a bit and feel strongly that while I cannot be certain my plans to incorporate the soft dome tweeter would be successful, I am more than comfortable trying based on some research and technical data that I learned. Of course, a worst-case scenario would be that if it didn’t work, I’d just go back to the original Focal tweeter. But as I have said, my interest in undertaking this project is now too low to warrant its undertaking as I am quite content with the performance of the Focal tweeter at this point. The Focal tweeter is not my system’s Achilles heel and therefore best to leave alone for the time being.

Now, back to the woofers-those wonderful Gotham v2 woofers whose integration with the S2s are currently the bane of my existence. There are basically two ways to set up the woofers. The first is the run the S2s full range and then bring in the Gotham using their own internal crossover, phase adjustment and gain. This the way I have helped set up Brian and Steve’s system. The idea is to let the S2s do most of the work, and bring the subs in very low (30-40 Hz) so that on most material, you don’t even hear the subs. But when the music calls for it, the subs fill out the bottom end most satisfactorily. The second way to add the subs is to use the formidable JL crossover that I have written about previously.

http://www.whatsbestforum.com/showt...T-digital-crossover&highlight=spectral+jersey

That’s the method I am currently exploring and it’s a work in progress. Remember, the Gotham’s are first set-up by using their auto EQ so the woofers are dsp’d below 100Hz. It is their fabulous dsp program that is what makes their use so attractive. You can talk to me about the merits of not using dsp until you are blue in the face, but in my experience, there is no substitute for the sort sonic benefits one can obtain with good EQ of the bass frequencies, and the Gotham’s dsp paradigm is outstanding in that regard. That does not mean I am using the subs up to 100 Hz. Rather I have the luxury of adjusting the crossover point (currently 42 Hz) and slope considerably and further work is necessary to extract maximum performance from the system.

All told, I am generally pleased with the limited work I have done to date to integrate the Gothams v2’s and the S2s to achieve a system with genuine low bass capability in addition to excellent performance in the rest of the frequency range. But I think I have considerably more work to do before achieving my final set-up. Stay tuned.

Click to expand...

marty said:

Now, back to the woofers-those wonderful Gotham v2 woofers whose integration with the S2s are currently the bane of my existence. There are basically two ways to set up the woofers. The first is the run the S2s full range and then bring in the Gotham using their own internal crossover, phase adjustment and gain. This the way I have helped set up Brian and Steve’s system. The idea is to let the S2s do most of the work, and bring the subs in very low (30-40 Hz) so that on most material, you don’t even hear the subs. But when the music calls for it, the subs fill out the bottom end most satisfactorily. The second way to add the subs is to use the formidable JL crossover that I have written about previously.

That does not mean I am using the subs up to 100 Hz. Rather I have the luxury of adjusting the crossover point (currently 42 Hz) and slope considerably and further work is necessary to extract maximum performance from the system.

All told, I am generally pleased with the limited work I have done to date to integrate the Gothams v2’s and the S2s to achieve a system with genuine low bass capability in addition to excellent performance in the rest of the frequency range. But I think I have considerably more work to do before achieving my final set-up. Stay tuned.

Click to expand...