Adagio EXtreme modification by Response Audio

Adagio EXtreme modification by Response Audio


January 2008


Extra Extra
Over the years I’ve had some mixed experiences regarding upgrades and modifications to high end audio equipment with a few of them leaving me wondering if it was really worth my time and expense to pack up one hundred pound amplifiers, or two hundred twenty-five pound loudspeakers and haul them over to UPS for a grueling trip across country and a date with the soldering iron. But once the gear finally made it back from a trip with the ‘Wizards of electronics’, untarnished and upgraded, with my wallet a few dollars lighter, I can truly say that the majority of the enhancements have been fairly positive and worth the exercise. 

With that in mind I was hoping that the upgrade path that I was about to embark on, the modification to the Acoustic Zen Adagio loudspeakers by Bill Baker of Response Audio would be just as successful. I had already reviewed the stock Adagios and I was curious to know if the Adagio EXtreme modification was truly an enhancement or just another one of those spurious claims towards greatness. So after an intensive and prolonged thought process (actually more like five minutes to search for the telephone number), I picked up the phone and called Mr. Baker in Endicott, New York. 

My conversation with Mr. Baker happened to be a lengthy one and after talking with him I thought that it would be a good idea to send him the stock Adagios for modification. So I began to pack up the Adagios for a ceremonious and labor intensive sendoff when Mr. Baker informed me that he had a pair that he had already ‘modded’ and that I could just sit tight and wait for the Adagio EXtremes to be delivered to Chicago. This way I could do a direct comparison between former and later. 

If the name Bill Baker has a familiar ring to it, it is probably because you have heard about his extensive modifications to Usher loudspeakers and Antique Sound Lab amplifiers. In 1996, coincidently the same year that he also started his modification business he also opened up the Response Audio high end retail audio store and has on display many two channel and home theatre brands including Acoustic Zen loudspeakers and Acoustic Zen cable products. Being so close to the Adagios is probably why he decided to dust off the ole’ soldering irons and modification overalls.

The Adagio loudspeakers by Acoustic Zen are very well known within audio circles and have received glowing reviews from a number of publications including this one; if you’re interested in finding out about extensive details regarding height, weight, and driver specifications, please don’t hesitate to refer to my previous review for detailed information about the stock Adagio’s because this modification is all about the internals, not the externals. 

When Robert Lee initially designed the Adagios he created a loudspeaker with a certain price point in mind. I felt he did a great job of producing a full range loudspeaker with special dual under hung mid/woofer drivers, ribbon tweeters, and a gorgeous finish that sounds very good for $4300.00. But at that price point Mr. Lee is limited in the types of crossover components he can use because some are cost prohibitive. 

The Adagio EXtreme modification employs a host of some of the finest passive components available to the audio industry. High quality air-core inductors, metallized poly film capacitors, and gold lead resistors make up the heart of the low pass filter. 

The high pass filter utilizes a number of Oil Impregnated Metallized Polypropylene capacitors and high quality Teflon film capacitors. Both are manufactured by Dan Wright of ModWright Instruments who is well known for his SWL 9.0 SE preamp. Bill Baker also uses top quality air core inductors and Mills non-inductive resistors in the critical part of the crossover.

All of the components of the crossovers are then hardwired and custom built on 1/2″ MDF boards to eliminate any signs of a pre-fabricated circuit board. There are two boards per speaker; one for the high pass and one for the low pass, and the crossovers are connected to upgraded metal WBT speaker binding posts and the tweeter and midrange drivers via high quality 14 gauge Continuous Cast Copper wire. He also uses a different type of internal stuffing material.

As I mentioned in my previous review of the stock Adagios, the ribbon tweeters already have a very flat impedance curve and overall the Adagios have a linear frequency response. The flat impedance curves means it is an exceptional speaker to mate with tube amplifiers and the modification according to Bill Baker didn’t change any of these characteristics.

Bill Baker’s goal with the Adagio EXtreme modifications is to bring more of the Adagio’s sonic potential to the surface and provide a new sense of voicing. He wanted greater resolution, more inner detail retrieval, enhanced dynamic extension, and more air up top and greater slam in the lower frequencies. In regard to voicing, he was after more liveliness and realism in the midrange without sacrificing the other aspects as mentioned previously. 

Since this a fairly new enhancement, the first prototype of the Adagio EXtreme modification has the crossover inside the loudspeaker. Future versions will have a separate outboard potted crossover box connected to the Adagio’s via a small 30 inch umbilical cord that has a Neutrik Speak-On connector on both ends. So after many hours of component substitution, testing, and listening Mr. Baker finally felt comfortable that he had an exceptional upgrade at a cost of $1695.00. 

Mot-to-the Max
Similar to most of the products in high end audio there is a period where the components usually benefit from having a constant signal run through them. Teflon happens to be one of those products and after about 400 hours I was ready to get started; well almost. 

I am also a firm believer in trying to enhance the sound of various high-end electronics and loudspeakers with aftermarket components so I substituted the supplied low cost spikes with specialty solid steel spikes from Soundcare Superpikes. I found that the Superspikes worked on both the stock and modified pair by tightening up the bass, providing a little more midrange transparency, and a little more extension up top. This is a tremendous tweak that I suggest you give some consideration to and it only cost a little over $150.00 U.S. I also tried a set of Star Sound Audiopoints on the Adagios but they dampened the sound too much and were a much better match for the Von Schweikert Vr4-jr’s. Just goes to show that some tweaks have merits but component matching is still important. 

My normal mode of operation when I get in a new piece of gear and I want to hear if it has the “right stuff” is to pull out some discs that contain female vocals; the reason is pretty simple: I like female vocalists and the majority of secular music that I listen too happens to be with a female behind the mike. On Gospel music it tends to be about fifty-fifty, male to female.

So I pulled out a few of my Gospel favorites and listened via the modified Adagios and immediately I knew that the music coming out was a noteworthy improvement over the stock speakers. The Adagio EXtreme modification maintained a neutral tonal balance, but with improved transparency and clarity. The high frequency presentation, which is one of the Adagios signature qualities, is also improved. There is an increase in the overall level of treble information and minute details are given a greater significance. At the low end of the spectrum there is just as much slam but the definition of the bass players is enhanced. Also noteworthy is an improvement in the Adagio Extremes’ ability to transform into a stealth performer.

In my review of the stock Adagios I mentioned how the loudspeakers are very adept at imaging but the EXtreme’s are even better at performing the disappearing act. The soundstage extended further beyond the outer boundaries of the speakers and is also much taller. With the stock Adagios the music is confined to a space in between the speakers whereas with the EXtremes I am presented with an expansive rectangular wall of musical artistry. 

The Adagio EXtremes soundstage is also deeper and creates more of an ambient musical presentation. With the EXtremes in place the music extended farther behind the speakers and created a multiple wave effect. On recordings that featured choirs that have a lot of members lined up in consecutive rows, I realized that there is more air between each one of the sections and I could hear the chorus of voices better, which brought me closer to how the choir sings live in the sanctuary.

I noticed that the same thing happened with orchestral music as well but this time it was with the sequential rows of violinist. It was easier to distinguish between the separate layers of string performers and that made it easier to create a more realistic picture of some of the concerts that I’ve heard at Symphony Center.

Normally when I attend an event at the Symphony Center I try and sit more towards the back and off right center because this way it gives the music an opportunity to breathe and fill the room, as opposed to being up close and getting bombarded with a massive rush of music. I noticed that the Extremes portrayed the music in a very similar fashion to when I sit in the later rows, with a warmer, more relaxed and highly textured presentation.

But getting back to music that really reaches down deep and touches my soul, one fine example is a recording by Pastor Kirbyjon Caldwell and the Windsor Village UMC Mass Choir titled, “Welcome to the Village” [7243 8 20367 2 2 EGD 20367] on EMI Gospel. Both lead singers Daryl Coley on “Holy is his Name” and Brian Wilson on “Awesome God” are outstanding. With the upgrade of some different components the Adagios still maintained the ability to convey music in an emotionally and stimulating way. I was still able to feel the healing power and awesome reverence that these songs are all about. 

Although secular, Mark Isham’s trumpet playing onBlue Sun [CK 67227 Columbia records] also traverses down deep just in a different way. Over the years he’s been compared to the late great Miles Davis because of his ability to play long, fluid, beautiful extended lines. Listening to a number of selections on Blue Sun including the intro track Barcelona, is motivating and pleasurable via the EXtremes. One of the signature traits of the Adagios is the ribbon tweeter and its wonderful ability to reproduce treble information without irritation compared to some of the low cost and even more expensive conventional tweeters on the market. With the EXtremes, percussion has more details and is more revealing and it does a better job of showcasing Mark Isham’s horn with a slightly less aggressive character and a warmer tone. Yet it does so without rounding off any of the notes or truncating any of the passages prematurely. Dynamics are also improved with the noise floor lowered and the transitions from quiet to loud passages beautifully orchestrated. 

Extremely Good
At $1695.00 plus initial shipping costs (return shipping is free) I must admit that it is a lot of money for an upgrade, especially when you consider that it is a forty percent premium to the stock Adagios. I also know that it will cause the bean counters to salivate at the chops when they play let’s count the component game to justify the cost and come up a little short in their calculations, even if Teflon capacitors are really expensive. But on more than one occasion I have had an opportunity to hear mega-priced loudspeakers with specialty drivers from well established vendors that didn’t sound very enticing let alone worth the outlandish prices that were advertised; any guesses on what the culprit might be? 

With the Adagio EXtreme modification that Bill Baker has developed for the stock Adagios, he has created a crossover that has improved on the performance without altering some of the fundamental characteristics that make the original Adagio so popular. The upgrade maintains a presentation that is highly detailed, coherent, with tight bass and crisp highs, but with a mélange of sounds that is musically aspiring. Listening to the Adagio EXtreme’s reminded me of that special feeling that I get when I’m treated to a complimentary upgrade from coach to business class, or when I’m moved from a standard room to a luxurious suite; that wonderful unexpected rush of emotional exuberance.

Therefore I can truly say that I’m glad I made that phone call to Endicott, New York and chatted with Bill Baker because I feel the modification was worth the effort and our discussions about his upgrades were quite informative. Mr. Baker through his “mod” is able to enhance the Adagios with a midrange that has a more liquid presentation, an incredibly open soundstage that has more substance and palpability, and a sweeter top end with greater attack and resolution. So when I take into account the total cost as a whole ($5995.00), I feel it competes with loudspeakers that are much more costly and I think you might have to look far and wide to find another bargain. 

However with all of those accomplishments I must report that at this time I do have one minor problem. Not only do I have to expend a lot of energy packing and preparing to send back the review pair of the Adagio EXtreme’s but I also have to prepare to send back my personal pair to Endicott, New York for a dose of some of that ‘EXtreme’ treatment. But at least this time I’m comforted in knowing in advance that this enhancement will be worthwhile and that I can chalk it up as another positive upgrade experience. 

Now if I could get my hands on a set of Bill Baker’s amplifiers. 


Response Audio
112 Carl Street
Endicott, New York 13760
Tel: (607) 785-9773
Price: $1695.00 USD


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