Last but not least, we come to the bass. For a number of reasons, some of which are inter-related, bass presents the greatest problems for a speaker. In no particular order:
1. Bass requires “moving a lot of air,” which places considerable demands on a woofer, including the cone itself, the support mechanism (basket, surround, etc.), and the motor assembly (magnet and voice coil.)
2. Bass response is critically dependent on the cabinet (ignoring for now, open baffle designs). The two most common designs — acoustic suspension (i.e., sealed cabinets) and bass reflex (i.e., ported designs) each has its own strengths and weakness, which translates to compromises.
3. Three desirable traits in a woofer are (a) bass extension, (b) efficiency, and (c) small enclosure. Hoffman’s Iron Law teaches that a design can have two, but not all three. Put another way, a designer picks the two qualities he most favors, but pays for it with the third.
4. Woofers have hefty power requirements, which puts limits on the choice of amplifiers (an issue I will return to in a moment).
5. Room interactions (i.e., nodes and standing waves) play a critical role in bass response, and are far more difficult to control than are high- and mid-reflections.
As I have written before in these pages, I am of the belief that every speaker should have an active crossover for the woofer, which would thus have its own amplifier. (The amp can be in the speaker or external.) This arrangement offers a number of advantages. First, by using an active crossover, the amp is connected directly to the woofer. By not having a crossover between the amp and woofer, the woofer benefits from the full damping factor of the amp. (In a typical scenario in which a passive crossover is situated between the amp and the woofer, the amp’s damping factor is severely reduced.) Second, because the woofer places the greatest demands on an amp, having a dedicated amp for the woofer allows one to use a wider variety of amps for the other drivers. Third, bass response varies enormously between rooms. Having a dedicated amp (with adjustments) for the woofer allows one to, at minimum, adjust the bass volume for the room.
As noted above, the Bache 001 AB, but not the 001PB, has a dedicated amp for the woofer. Not surprisingly, the two speakers — which are otherwise identical — vary significantly in their bass response, especially with lower-powered amps. When used with the 30 W/channel Soul amps, the woofer of the passive 0001PB was poorly controlled. This manifested as flabby or tubby bass response, with a lot of overhang. In other words, poor transient response. Things improved dramatically when I switched to the Veritas amps, which have enormous power (400 W into 8 Ohms) and equally if not more important, a very high damping factor. With the Veritas the bass was much improved. It was considerably tighter than with the Soul amps, and went deeper. All-in-all, it was improved, but not – as we shall soon see – -as good as it could be.
Switching to the active 001 AB was transformative. I began by using the Soul amps powering the Tangband/Fostex array. The Souls are a hybrid design, in which solid state is used in the input section to provide proper voltage and current to the parallel single ended KT88 output tubes. Whereas I find most tube amps to be sluggish and deeply colored, the Souls (which have very wide bandwidth) are fast, and not at all tubey-sounding. They sounded terrific with the 001 AB’s, allowing the speed of the Tangband to manifest, with just a touch of midrange bloom. The bass, powered by the internal; BASH amp, was far more articulate than was the passive 0001 AB. It had a lot of detail (yes, bass should have detail), with relatively good transient response. It went quite deep and had good power, especially given it’s reasonably modest footprint. As a general rule I prefer speakers with front-firing woofers, as these seem to have better “attack.” That said, the Bache’s downward firing woofer, which operates only from 100 Hz and down, performed well in this regard. All in all, the bas was improved in every parameter, as compared to the passive version.
I next switched to the Veritas amps. My expectation was that — unlike the situation with the passive 001 PB — this would offer no improvement in the bass. I was wrong! To my amazement, the bass got even tighter, with better transient attack, and less overhang. I don’t know if this is the result of the Veritas’ greater power, greater damping factor, or lower distortion, or some combination thereof. Whatever the reason, the results were significant, though certainly not as great as with the passive version. Of course, the Veritas’s power, speed and low distortion also manifested superbly with the mid and upper frequencies. The Veritas was my amp of choice with the 001 PB, as it has become with a variety of other speakers.
As should be apparent, I strongly preferred the active 0001 AB to the passive 001 PB.
Conclusions
High bandwidth drivers have something of a cult following. Though they have many desirable properties, they also have a number of all-too-obvious deficiencies. Bache Audio has done an admirable job of building an “augmented widebander” speaker with a modest foot print, and a modest (by high-end audiophile standards) price, that wisely uses a widebander where it works best, without pushing it beyond its limits. It does so by supplementing it above with a tweeter, and below with a woofer. In designing the speaker, Bache made number of wise decisions. First, was the choice of the main driver, the Tangband W8-1772. Unlike many widebanders, this driver is devoid of the shout that plagues many other widebanders. Second, was the decision to remove the whizzer cone. This effectively eliminated the W8-1772’s most significant coloration. Third, was the choice of the Fostex FT-96 EX-2, which is a very fine tweeter. Fourth, was the use of minimal crossovers. Fifth and last, was the inclusion of a self-powered woofer. Of course, this last decision is applicable only to the active version. Throughout the review period, I repeatedly told Gregory to scrap the passive version, as I feel that it gives up one of the speaker’s most important benefits, and offers only a $950 savings. Gregory feels that some audiophiles – -in particular — SETophiles – -will be reluctant to use a speaker with a solid state amp driving the woofer. Alas, he is correct, as I learned from one visitor to my room. As I told Gregory, as I told that visitor, and as I tell you dear reader, such thinking is missing the forest for the trees. Does your precious SET amp sound “better” than the BASH amp? In some sense, absolutely. But the relevant question is this: Can your low powered SET amp, with its mediocre (actually, poor) damping factor, a damping factor made even worse by the passive crossover between it and the speaker, properly control a 10” woofer? The answer is unequivocally, no. In response to my listening impressions — or perhaps just to appease me — Gregory is promoting the passive version for those who prefer to use higher powered amps, and the active version for those who prefer low-or high powered amps. Of course, those who are already using a high powered amp (which is likely to be solid state) are less likely than SETophiles to object to the internal BASH amp. And as I discussed above, I preferred the active over the passive version, even when used with a high powered amp.
What all the above boils down to, is this: For anyone considering the passive 001 PB, spend the extra $950 and get the active 001 AB. The active version is considerably better than the passive version, without any downsides (other than the extra cost). I enthusiastically recommend the active version. Though not perfect, it excels in many of the qualities I find most important in a speaker. In particular, it is dynamic; superbly coherent; full-range (or very nearly so); easy to drive (especially important for listeners favoring lower powered amps); with a detailed yet sweet midrange that is never grating; and with a woofer that can be adjusted for the listener’s room. Add to that it has a modest foot print, is attractive, doesn’t cost as much as a car, and it manufactured right here in the U.S. of A. In Brooklyn in fact, for those who care about such things!
There are many speakers in the $10,000 range. However, only a handful (to the best of my knowledge) are based around a wideband driver, and offer the benefits of a powered woofer. Those who favor such a design, or are intrigued by it, should give the Bache 001 a listen. I enjoyed my time spent with this speaker, and will miss it.
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