The Sapphire XL is a complete re-design of a true audio classic. Based on the ScanSpeak Revelator woofer, the XL is the most advanced monitor we've ever built. Compared to previous Sapphires, the XL has more air, greater transparency, broader and deeper image, and more of a "see through" quality.

Tube amp FAQ:

We often get questions regarding the use of various ACI models with tube amplifiers.

It must be understood that everyone has different tastes and sonic priorities. What one person may consider, "loud enough", and or dynamic enough, may be insufficient to someone else.

The size of the room is very important. Large rooms typically require far more amplifier power to fill. A related issue is distance of the listener to the speakers. Some audiophiles like to set up their speakers so they are listening quite close; this reduces the need for high power. Conversely, sitting far away from the speakers in a large room requires more amplifier power.

Using a powered subwoofer(s) in the system can go a long way toward improving system dynamics, even with low-powered amps. For example, using a Titan sub with a pair of our passive 85Hz filters at the input of the main amp will make a huge improvement in dynamics. Often, the net effect is greater than if you were to more than double amplifier power! Freeing the main amp of signal below 85Hz really frees up the amp to do a better and more dynamic job in the upper-bass-mids-highs.

We can easily recommend tube amps of 25-30 watts/per channel and on up. This is sufficient power to comfortably drive models like our Sapphire XL, Panorama or Emerald to good levels. In many rooms/systems, a good 25-30 watts of tube power will yield reasonable dynamics as well as overall satisfying sound.

Low powered direct SET amps of approximately 2-10 watts per channel are a different story. Some audiophiles love the sound of these amplifiers. However, most of these amplifiers work best with very sensitive speakers, often large, horn-loaded speakers. Will one of these amplifiers be powerful enough for a pair of Sapphire XLs? We recently spent time listening to a 6 watt SET amp on playing through the Sapphire XLs. The marketing director for the company that builds the amp commented on how good the combination sounded. He said, "you can tell your customers that this speaker is certainly very tube friendly". Again, this is matter of personal preference, the room and whether you are using a powered subwoofer(s) or not.

Our best advice? Be reasonable about evaluating your needs. Consider using a powered sub(s) and passive high-pass filters to improve your dynamics, (this will also improve ambience and depth of soundstage). As always, we recommend trying any amplifier – speaker combination in your home listening environment. You want to be able to trade or get a refund if the combination isn’t what you want.

Why are the correct stands important for a speaker like the Sapphire XL?

The Sapphire XL is designed such that the best sound is when your ears are at about tweeter height. Sitting or standing significantly lower or higher than this "sweet spot" results in a less than optimum frequency response and a defocused stereo image. This is not a problem for most music lovers. With the Sapphire XL mounted on a 24- 26" stand it will be at the correct listening height for a seated listener. A standing listener may notice some loss of depth and slight midrange coloration. The music will still be enjoyable for the standing person, just not as "perfect". Keep in mind that for serious listening the best response will be with the listener seated.

How do I setup and adjust a subwoofer in my system?

Integrating a sub is a process that requires following ordered steps. I find it easy in some rooms/systems, and very time consuming in other rooms/systems. The key is to eliminate each variable one at a time. The ACI Subwoofer Test CD. (free with ACI subs), really helps.

Determine placement of the sub. This is often a matter of "where it will fit" in the room. If you have greater flexibility, begin with a corner placement behind the main speakers. A corner placement behind the main speakers usually yields the deepest, cleanest bass. As long as the subwoofer is correctly adjusted it will not be boomy or overbearing. Second best placement is usually close to the wall behind the main speakers.
Set crossover frequency at 100Hz and adjust level to be easily audible.
Use your test CD with a tone at about 100Hz or a repetitious bass line to adjust the phase for maximum output at the listening position. This is most easily accomplished with an extra person to work the switch / control.
Turn frequency and output controls all the way down. As you play music with a repetitious line, adjust the bass level upward until it is just consistently audible.
Turn frequency control up gradually until the bass seems full, and then back it off just a bit.
Sit back and listen with a variety of music, play with only the level until it seems just right, you're just try to fill in the bottom so most likely the level control will be just barely on.
If the music seems to lack warmth, try adjusting the frequency control up just a bit at a time. Too much, and the sub becomes easily audible by itself.

Additional considerations:

You'll never get it perfect for all music because the music isn't recorded consistently! If you try to use the sub to adjust for recordings that lack bass you'll go nuts, adjust the sub to well recorded music and leave it alone.
If your main speakers have ports (vents) try stuffing them; this often improves the transition drastically. The ports can easily be stuffed with cloth. Stuffing the port changes the response from fourth order to second order and yields a more gradual rolloff in the main speakers. It can make all the difference in the world!
If you have a separate amplifier, use our passive plug-in high-pass filters, they make major improvements to every system they are used with.
VERY IMPORTANT! Take the time to read and understand the details in the manual provided with your ACI sub. That last 10% of performance may take a lot of work, but will be worth it if you want a superb sounding system.

Can your provide SPL measurements for the Titan XL, Force XL or Maestro XL?

Some people think you can tell what you need to about a subwoofer's performance from simple SPL measurements. Say, maximum SPL at 20Hz with 10% distortion. There is some truth to this if all you're after is clean and loud movie special effects. If loud is all you want, then frankly, the Titan or Force may not necessarily your best choices. If however, things like music, build quality and appearance are important to you, then read on.

A little story might help show why measurements tell so little about how satisfied you'll be with a product. I recently purchased a new car. I began by reading reviews and studying specs on the web and in the car magazines. I did a lot of comparing of the specs to my current vehicles. I narrowed it down to a couple of cars that I test drove. Guess what. After a 15-minute test drive I completely dismissed what had seemed to be an easy winner. It was more cramped inside than the specs indicated. It did not feel as quick as the numbers said it was. The interior quality level was not what I was looking for. The ride was too coarse. I ended up being very happy with a vehicle that had been near the bottom of the rankings based on the "specs". Lesson learned, the specs and reviews are great for narrowing down the choices. However, there is no substitute for trying out the real products yourself. More on ACI Subwoofer Quality.

Forward vs. Down-Firing Subs

I've been building, testing, and listening to subwoofers since the late 70s. I can state categorically that forward facing subs only have an advantage IF the crossover frequency from the sub to the main speakers is rather high, usually above about 100Hz or so. At these frequencies you are pretty much going to need a pair of subs.

At lower frequencies, there is very little difference in the performance of a down-firing vs. a forward firing sub. If anything, the down firing sub will have a slight advantage in lower perceived distortion at extreme output levels. Why? Because the harmonics, (distortion components), are directional and will be more apparent if the woofer cone is aimed directly at the listener rather than diffused by the floor.

All three of our subwoofer models are available as forward firing units for custom install. Direct A-B comparisons of these models with their down firing "twins" yields no significant difference in sound quality.

Subwoofer sound quality is determined by many factors including: driver design and construction, cabinet design and construction, internal damping, and amplifier design and construction. These factors yield real, measurable and audible differences between subwoofers. Down-firing vs. forward firing is just not a factor.

Troubleshooting subwoofer hum or noise problems

If you have a problem with hum there are generally three possible causes:

Ground loops are the most common cause of subwoofer hum. Turn everything off and remove all connections from the sub to the rest of the system. Turn the Force back on. If the hum is still there, it might be a problem with the Force or a bad cable. If the hum is gone, the problem is probably caused by a ground loop elsewhere in the system, or improperly connected household wiring.
Poor connections or RCA interconnects can cause hum. If you move the shielded cable that connects the sub to your system and you hear a change in the hum it is likely you have poor shielding or a defective RCA plug. Replace the cable.
Amplifier damage is the least likely cause of hum. However, if you have ruled out ground loops or a defective connecting cable, it is possible that there is a problem with the amplifier in your sub.

Occasional a Force XL or Titan XL will develop a slight mechanical hum. The windings on the transformer have heated up and cooled down and have shifted ever so slightly and now are causing the hum.

It is simple to eliminate the hum. First, unplug the amp and let it set 5 minutes to allow all the energy stored in the capacitors to dissipate. Remove the six screws that hold the amp to the cabinet. You will notice that the round, torroidal transformer is held in place by a bolt that runs through the middle of the transformer and is terminated with a Phillips head in the middle of the heatsink area on the outside of the amp. You will need to loosen the nut with a wrench while holding the screw with a Phillips head screw driver. With the nut loose, rotate the transformer about 1/4" to the right or left and tighten the nut down onto the transformer. Secure the amp back into the cabinet, plug it in and you are ready to go.

Stereo subs

We are often asked, “What about stereo subs vs. a single mono sub? As we move down in frequency, it becomes more and more difficult to locate the sound source. This is in part because of the human hearing mechanism and because the wavelengths are getting longer and longer. The wavelength at 80Hz is approx. 14’, at 40Hz it is 28’ and so on. You will hear statements such as “bass is non-directional”. However, there is not a specific frequency at which this instantly happens, and it varies with individual listeners. When this occurs is also a function of the design of the sub(s) as well as room placement, proper integration of the sub(s), and associated equipment. In practice, some people, in some situations won’t be able to localize a single subwoofer crossed over above 100Hz. Other people, in other setups may be able to localize a single sub crossed over well below 80Hz.

For those people looking for the absolute ultimate two-channel musical performance we recommend considering a stereo pair of subwoofers. This of course requires room and budget. It also requires a dedication of commitment by the enthusiast to spend the time needed to optimize placement and adjustment. While a stereo pair of subwoofers doesn’t have to be more difficult to optimize, it can be more time consuming. For those willing to invest the time and money, what can they expect to gain? A stereo pair of subs will offer improvements in the quality of bass and increase the sense of space and soundstage. A stereo pair of subs is the gold standard for bass reproduction in a high-end two channel systems.

How do I get better imaging from my speakers?

The majority of us have to make do with a multi-purpose room. Most speakers sound their best when they are well away from room walls, (subs are an exception to this, and they usually do their best up against the walls or even in a corner). In fact, it is almost impossible to get a good sense of depth from two speakers unless they are well away from the rear wall. Audiophiles with dedicated listening rooms often find the best overall sound is by following the "rule of thirds".

So what do you do when you have to share this room with a significant other, kids, bookshelves and a parakeet? You use a pair of movable speakers! Most of the time you have them nicely out-of-the-way, back near the wall. When it’s time for a home-concert, you simply pull them out as pictured! A couple of lengths of string can be cut for each speaker to make it easy to get them placed exactly where you want, quickly and easily. When the family wants to re-claim the room, simply move the speaker's back as far as necessary.

How close can I put a non-shielded speaker to a TV screen?

Placement depends on the speaker and the Television screen. Speakers with more/bigger magnets have stronger magnetic fields. Typically, a non-shielded speaker needs to be about 15"-20" away from a TV screen to prevent picture distortion. The easiest way to determine the minimum distance is by trial and error. Simply move the speaker gradually closer to the screen until you just start to see picture distortion in the nearest edge/corner. At that point move the speaker a couple of inches away and you're good to go!

Is it possible to add shielding to a non-shielded speaker?

Sorry, it just isn't practical. Shielding requires the addition of extra-magnets and containment cups. This is something that can only be done correctly by an experienced designer/engineer.

Why is our vertical mid-tweeter array better than most center channel speakers?

Most center channel speakers are mounted horizontally under or above a screen. Most center speakers feature an MTM arrangement with a tweeter between two bass-midrange drivers. Any experienced speaker designer/engineer will explain to you that "laying this down" is not desirable. Why? An MTM design is meant for vertical orientation. When an MTM is "laying down" it has poor response left and right of center and directs too much energy towards the floor and ceiling!

So why are so many center speakers marketed and placed on their sides? Because they fit better on their sides. And the marketers know they'll sell more if they just keep their mouths shut and act like they're designed that way! Sure, a speaker designed for vertical placement will still sound okay if lying on its side, but it will sound better if standing up. Often the center speaker will not fit the entertainment center if it is standing up so it must be laid on its side.

The ACI XLC has a vertical midrange - tweeter array. This dispersion pattern yields a major improvement in dialog clarity as well as improved response for listeners seated to the sides, The Emerald XL has an advantage because it is not as wide as many center speakers and can fit where many other speakers can't. If it must by placed on it's side it will still work as well or better than the MTM designs placed on their sides.

Surround Sound System speaker placement recommendations

Dolby Labs has diagrams and explanations for optimum placement of speakers in 5.1 and 7.1 systems. http://www.dolby.com/consumer/home_entertainment/roomlayout.html

Why are ACI speakers sometimes backordered?

In spite of our best effort, backorders of one two to two months have been common. Luckily for us, most customers are willing to wait, although some aren’t exactly happy about it! It’s not that we don’t try to keep up, but each of our speakers requires a considerable amount of craftsmanship. In essence, these speakers are limited edition pieces of music-playing-furniture that is built to last a lifetime. We work with the finest finest cabinet makers to deliver true Ethan Allen furniture quality.

These speakers are well worth the wait, but we’ve made it a priority to try to better anticipate demand and reduce the amount of time you wait.

Can you refer me to a customer's home to hear ACI speakers?

Customer privacy is something we take very seriously. We feel that it would be quite an imposition to ask our customers to act as dealers for us. In this case, dealers working for free! I know some other audio companies do ask this of their customers, we just don't feel right about it. ACI customers tend to be different than some other audio buyers. Over the past 26 years we have found that ACI customers are music lovers who seek long-term satisfaction, they are not looking for the latest "speaker of the month" so they can sell and start over again in a few months. They purchase ACI speakers to enjoy for many years. Notice how few ACI speakers are available on the used market?

We also believe strongly that brief demos, no matter how well done, tell very little about how a speaker system will satisfy in the long run. Our customers agree, only by listening to an ACI system over a period of at least a couple of weeks will you begin to experience the long-term musical satisfaction you deserve.

Our money-back guarantee is your strongest tool in finding long-term satisfaction. Order the ACI system you want, install it in your system, break it in thoroughly and really listen for a whole month! Will the system be everything you want? You'll have no doubts when you've really listened. If for any reason you find that it isn't perfect for you, the return process is totally hassle free. You'll only have invested the return shipping charges, typically only 3% to 4% of the system cost!

So you still wish you could here some ACI speakers before purchase? We have a wonderful showroom, only eight miles from our office, available by appointment only, email sales@audioc.com Also, check out the office ACI Forum and you may be able to post and find an ACI owner near you who will be willing to let you hear their system. www.audiocircle.com

Does ACI take trade-ins?

We have not found an effective way to do trade-ins. By the time you factor in the shipping to us, repackaging etc., we can't offer you a very high price. A better solution is to sell directly through on-line classifieds. By eliminating the middle man, (in this case us:)) you can sell at the best price for yourself AND the buyer. There are many places on the web to sell used audio gear and we've found Audiogon is a particularly effective place to sell used ACI products. Customers report getting very high resale value when selling on Audiogon. Used ACI speakers are relatively rare on the market and usually sell quite quickly. ACI speaker system have by far, some of the highest resale values in the audio industry.

About the passive components we use in ACI systems

Early on in our 30-year history, ACI made pretty good money selling various passive crossover components. You may remember the famous Wonder Cap. As our R&D became stronger, we began to take a hard look, (listen), to various passive components. About this time, we began to hear certainly little industry "dirty secrets". Now, about twenty five years later will sum it up by saying "Do not believe 1/5 of what you hear about the "sound" of passive components." Passive components represent one of the most profitable segments of hi-fi. ACI has always been about value. If a more expensive part improves the sound proportionately, you can be darn sure we'll use it. All the parts we use are very carefully selected for what we feel to be the optimum performance and long-term reliability. It is very important to realize that crossover will not perform their best unless each part is very close to the actual target value. The industry standard is a 10% tolerance. ACI standard is to match to within a fraction of 1% per stereo pair. Typically, .1% (1/10 of 1%). 100 times tighter than the industry standard. Another concrete reason ACI speakers sound fantastic.

What receiver/ amplifier/ processor etc. should I purchase for my ACI Home-Theater system?

Audio-video electronics seem to change daily. We've found it impossible to keep up with all the latest developments. We try to be a sounding board for your ideas of what equipment you'll use with our speakers. This is best accomplished with an E-mail message or a phone call. We can't guarantee we'll be able to make specific recommendations because there are so many variables involved, and the equipment available changes so rapidly.

We suggest you take as much time as possible to study the equipment available to you. Determine what features you require, consider where you'll be purchasing from. If possible, arrange an "In-Home-Trial" to see for yourself if the gear meets your needs. You are the best judge of a component's worth to you.

What's the difference between a "home-theater sub" and a sub built for music?

Essentially, the requirements for a good sub for music and HT should be the same, but in many people's minds there are differences. For most HT enthusiasts the requirements are; to play loudly enough with low distortion, and to reach to about 30-35Hz. Some HT enthusiasts also want full-power extension to below 20Hz. These conditions are reasonably easy to meet. A sub that simply meets these criteria will sound passable if not great with most movie soundtracks.

Realistic music reproduction and state-of-the-art HT is more difficult. Of course the above conditions must be met, but at least four more factors become important:

The transient response of the system (damping). Simply put, good transient response means the woofer will start and stop as quickly as the impulse delivered to it. Poor transient response results in a heavy, muddy, ill-defined bass quality. ( Critical HT listeners will also be bothered by this, but a bass that is slightly muddy on sound effects can be absolutely disgusting when listening to musical instruments ). The transient response of the sub is primarily measured by the system Q, ( a measure of damping). The system Q is a function of the woofer, cabinet size and electronics used. A lower Q means better damping. Why not just design all subs with a low Q? The lower the Q, the larger the box must be. Further, in a quick listening check the higher Q system will sound like it has more bass, because it does! It is the classic quantity vs. quality situation. Higher Q systems sound more impressive in store demos, etc. However, it often doesn't take long for the high Q bass to become overbearing and irritating. Sort of like turning the bass control up too high. Initially it sounds fuller, but soon sounds heavy and leaden. The Titan, Force and Maestro have system Qs of approximately .6. compared to many subs with Qs from 1-1.5.
The upper range performance and crossover transition of the subwoofer is critically important for musical reproduction. For years, audio perfectionists complained that although they liked the added bass they could get with subs, the "discontinuity" and poor blending was irritating and unacceptable. For over nine years, the Titan series has earned a strong recommendation as one of the few subs at any price that will seamlessly blend into any music/HT system. We have spent a great deal of time on developing and implementing filters that will help achieve a seamless transition. You musical satisfaction depends on it.
The "strength" of the cabinet. A solid, non-resonant cabinet will not add its own coloration to the sound. This coloration is caused by the out-of-phase energy radiated by the vibrating walls of a cabinet. In a poorly constructed cabinet, this out-of-phase energy can be substantial. This resonance not only distorts the sound, but often makes it much easier to localize the subwoofer. Instead of the bass seeming to come from the main speakers, it comes directly from the sub. The Titan, Force, and Maestro utilize extremely heavy and non-resonant enclosures. In fact, the Titan's 70 pound weight is comparable to many subs that cost twice as much and are nearly twice as large physically!
Extension to 20Hz ensures that all the fundamentals will be played accurately. Moreover, the sound of "space" in many large areas is enhanced by the "hall" sound which has a considerable amount of low-bass content. Ever notice the "sound" when you walk into a quiet cathedral or arena? That spaciousness is enhanced by a subwoofer that extends cleanly to 20Hz. We designed the Titan and Force to extend cleanly to 20Hz. We also have sophisticated limiting circuits that protect the woofer from over-excursion, damage or distortion at these extreme low frequencies.

Our philosophy with our subs has always been, not necessarily the most, but the best quality of bass. A single ACI sub will usually play more than loud enough for most listeners. Multiple units can be used for higher output levels and true stereo bass. Video soundtracks not only sound "spectacular", but accurate through these subs. Most importantly, the sound an ACI sub is so accurate it will never be obnoxious or irritating. It is meant to please for the long haul!

How do the Titan XL, Force XL, and Maestro XL match up with planars such as Magnapans?

ACI subs are recognized as two of the finest possible subwoofer choices for use with planar speakers. Few subs will allow a completely seamless transition to the Maggies. The Force, Titan, and Maestro will not only integrate seamlessly, but the Maggies often sound better when high-passed so they don't have to do the lowest bass. The upper-bass and lower midrange lose congestion and take on greater clarity. The Titan, Force, and Maestro with their dual filters, and crossover as low as 35Hz will provide the best possible transition and rock-solid bass response. Do some searches on the Planar Forum at Audioasylum.com and you will see the high-regard that planar users have for ACI subwoofers.

Could the Maestro XL be purchased without the amplifier?

There is no reason you could not purchase the Maestro XL without the amp, except it wouldn't be a Maestro XL, in fact it wouldn't be close. Instead of a raging beast capable of potent sub 20Hz output it would simply be a very good sealed box woofer that rolls off in the mid 30s. In fact, it wouldn't be as quick, as tight or as articulate. The fact is, the amplifier is far more than that. It equalizes the response to linear under 20Hz, it keeps the system Q under .6, and it provides four separate bands of variable limiting (this is a real key to the subjective performance, part of why it is so powerful yet transparent). The amplifier also provides 0-180 degree phase control as well as adjustable 24db/oct low pass filters. This custom, ICE based amp is actually capable of peaks far exceeding the conservative 500 watt, RMS at .5% distortion rating.

How do I take care of a Piano Gloss Finish?

The Piano Gloss finish is essentially an automotive finish and can be cleaned and "repaired" in a similar manner.

Usually, the finish can be easily cleaned by gently rubbing with the supplied MicroFiber cloth. Sometimes it helps to "fog" the area with your breath like you were cleaning a pair of glasses.

If there are rub marks, finger prints, etc. that aren’t coming out with just the cloth, try Meguiar's Quick Detailer Mist & Wipe. This product can be purchased at just about any place that sells automotive waxes and such.

If the finish has been dulled by something rubbing against it, or finely scratched it can be repaired using other Meguiars products. Meguiar's Mirror Glaze, Show Car Glaze #7 is a good place to start. It is very gentle. If #7 isn’t aggressive enough, start with the #4 version, then follow-up with #7 (the lower the number the more abrasive it is). After rubbing out by hand you can remove any residue using a clean cloth.

Note: Please go to individual speaker pages for further faqs.

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