some more review about HSU Research Subwoofers
DFX Australia
Don Keele, Audio, August 1998
Measurements
To assess the Hsu Research TN1220HO's frequency response, I made
ground-plane measurements, placing my test microphone 2 meters from the port
and driver. The results are identical to those from standard, 1 meter,
anechoic measurements.
Figure 1A, made with no crossover filtering or equalization and no curve
smoothing, shows fairly flat response between 45 and 160 Hz, with a 6 dB/Oct
rolloff below 45 Hz that becomes steeper below 15 Hz. Above 160 Hz, the
response is quite rough and choppy. The high Q dip at 230 Hz reflects the
primary organ-pipe resonance of the port tube, whose length is approximately
one-half this wavelength. Averaged over the 1220's flat response region,
sensitivity is 82.5 dB SPL for the 2.83-volt input signal, significantly
below Hsu's 93 dB rating.
The Hsu electronic crossover's response (Fig. 1B) confirms that it uses the
classic Linkwitz-Riley alignment, whose outputs sum to unity gain when
combined. (The acoustical outputs of speakers will generally not combine so
neatly, of course, because of variations in their individual magnitude and
phase characteristics.) The rapid 24 dB/Oct slopes should minimize response
overlap between the subwoofer and satellite speakers. At the other end of
the subwoofer output's bandpass is an underdamped second-order 12-dB/Oct
high pass filter with a 6 dB peak at 17 Hz. This filter rolls off rapidly
below the woofer system's tuning frequency, to minimize cine excursion at
infrasonic frequencies. It also adds a touch of equalization, flattening the
subwoofer's low-frequency response.
This flattening can be seen by comparing the subwoofer's response with the
crossover (Fig. 1C) and the unequalized response seen in Fig. 1A; the - 3dB
points are now at 15 Hz, which is quite low, and 91 Hz. The upper rolloff
point coincides excatly with Hsu's rated crossover frequency (even though
the electrical crossover seen in Fig. 1B is 95 Hz), and the rolloff itself
eliminates the upper frequency roughness seen in Fig. 1A.
A plot of the TN1220HO's impedance magnitude (Fig. 2) displays the double
humps typical of vented boxes. The impedance minimum, 5.9 ohms, occurs at
17.5 Hz, the approximate vented box tuning frequency. The peaks of 12.1 and
13.9 ohms are reached at 10 and 40 Hz. The voice coil's inductance causes
the steady rise in impedance above 200 Hz. Below 200 Hz, the impedance
variation is only 2.4 to 1 (13.9 divided by 5.9). To keep cable drop effects
from causing peaks and dips greater than 0.1 dB, an extremely tight spec for
a subwoofer, cable series resistance should be limited to a maximum of 0.12
ohm. For a typical run of about 10 feet, that would correspond to 18-guage
(or larger) cable.
The effects of frequency and output level (including room gain) on the
TN1220HO's harmonic distortion are shown in Fig. 3. Note that the lowest
test frequency is 16 Hz, not the 20 Hz I've used in prior subwoofer reviews.
The distortion presented is the sum of the first 10 harmonics, expressed as
a percentage of the power in the fundamental. This method essentially yields
the same results as total harmonic distortion (THD), but uses only the first
10 harmonics and does not include noise.
Although the measured distortion reached 10% to 20% at full power, the
TN1220HO sounded quite clean because the second and third harmonics
predominated [get two and tie them together in push-pull mode and cut
distortion in half and cancel all reactive forces]. Distortion at 40 Hz was
significantly lower than in the other bands, reaching only 7.2% at a high
108 dB SPL, the highest sound level reached at any of the frequencies
exhibited here. At 16 Hz, the fundamental rose to an impressive 104 dB,
although distortion was a fairly high 22% at that level. Very few subwoofers
have much usable output at 16 Hz, but the Hsu had enough output here (and at
20 Hz) to vibrate every loose object in my listening room.
When I drove the TN1220HO with a high level swept sine wave, its cylindrical
cabinet exhibited no wall vibrations whatsoever, - surprising rigidity,
considering its large size and very light weight. Nor could I hear any wind
noise caused by vent turbulence, even at the highest input levels and near
box resonance, where air velocity through the port is highest. A strong dip
in the woofer's excursion at 18 Hz confirmed that the box resonance was at
about that frequency. In free air, the woofer's maximum excursion was about
1 inch peak-to-peak at 20 Hz. When the woofer was remounted in the box and
energized at high levels, I observe some inward dynamic offset between 60
and 80 Hz.
I plotted the TN1220HO's short-term peak power input and sound output (Fig.
4) from 12.5 Hz up instead of from the 20 Hz I've used for other subwoofers.
The Hsu's peak power input capability starts at a fairly high 150 watts at
12.5 Hz, then rises through 660 Watts at 16 Hz to a high of 1.35 kW at 20
Hz, then stays at about 1 to 1.2 kW from 25 to 75 Hz. At higher frequencies,
the input power rises rapidly, reaching 6,550 watts at 200 Hz.
With room gain, the maximum peak acoustic output starts with a very high 101
dB at a very low 12.5 Hz, passes through 110 dB at 16 Hz, then rises rapidly
to a local peak of 114 dB at 20 Hz. After a slight dip to 113 dB at 25 Hz,
the output rises to 117.5 dB at 50 Hz, heading up (after another slight dip)
to 120 dB at 95 Hz before falling slightly to 118 dB at 200 Hz.
The Hsu Research TN1220HO's output at 25 Hz [and below] is the loudest, if
perhaps not the cleanest, of any subwoofer I have tested. At 30 Hz and
above, however, several speakers and subwoofers can play louder. Overall,
the Hsu's low frequency output is still well into the top 10 % of all
subwoofers and speakers I have tested.
Use and Listening Tests
The tubular Hsu TN1220HO is distinctively different from the usual cube
subwoofers. When I unpacked the Hsu, I was pleasantly surprised at its light
weight. Its very easy to pick up and move around: just lift it, bear-hug
style, and move it where you want it. To move it further distances, you can
flip it on its side and carry it under one arm. The speaker's grille-cloth
may shift and wrinkle if you use the bear-hug technique, but it can easily
be smoothed out.
One of the first things I did when I unpacked the subwoofer was to check the
length of its port tube by physically reaching into the port with my hand
and arm and trying to find its end. The port handled the full length of my
arm without my hand touching its end; long indeed! (Actually, I was glad I
was easily able to get my arm out, I would look stupid with my arm stuck in
the bottom of the latest subwoofer I was reviewing for Audio!)
The top-mounted driver, however, makes the 1220 quite top-heavy and
susceptible to tipping, as the brief owner's manual warns. The manual covers
unpacking procedures and subwoofer placement, as well as troubleshooting and
it adequately explains how to connect the subwoofer to many types of home
theater and music systems. In addition to the warning about tipping, the
manual cautions you not to set the 1220 upright on hard floors, such as tile
or concrete, without putting a throw rug, felt pads, or rubber cups under
the pointed feet to keep them from vibrating. Apparently, the cabinet's
rigidity helps the driver's reaction forces travel to the floor, but its
weight is too low to keep those vibrations from making it jump around when
the 1220 is playing loud!
I evaluated the Hsu subwoofer in my home theater setup with both video
soundtracks and music, feeding the output of the Hsu Electronic Crossover
through a Crown Macro Reference amplifier that powered the TN1220HO through
a 5-foot length of 16-guage zip cord. For comparisons, I used the Paradigm
15, the best-performing subwoofer I have reviewed to date (Audio, April
1998), which I fed through its own crossover and amp. The other speakers in
my home theater setup were all KEFs: Reference Four main speakers, a Model
200C in the center, and Reference Twos for surround. I setup the Paradigm
and Hsu subwoofers side by side in one corner at the front of the room. The
Paradigm's woofer and the bottom center of the Hsu were each approximately 2
feet from the corner. (The Hsu's manual suggests that placing the 1220 near
your listening position may also work well).
Initially I listened to selections culled from Hsu's very useful list of CDs
and laserdiscs carrying deep bass signals. The TN1220HO demonstrated that it
could keep up with the best subwoofers I've had in my listening room; its
output at very low frequencies was second to none, while its bass reserve
capabilities, smoothness and extension were excellent. On a broad range of
program material, the TN1220HO was able to handle , most capably, just about
everything I threw at it. And although I listened mostly to CDs, the first
10 minutes of the Terminator 2: Judgement Day laserdisc demonstrated how
ably the TN1220HO could handle even the very demanding low-frequency effects
in the "Future War" chapter.
The Hsu subwoofer competed very well with the Paradigm, its maximum clean
output being a bit greater at the lowest frequencies and about equal at the
higher end of its range. The Paradigm was somewhat cleaner in the upper
bass, but I could hear this difference only on music that hadn't much
upper-frequency content to mask it; it was audible on solo bass guitar or
pipe organ pedal notes, but not when the organ had all its stops out.
On band limited pink noise in the 16- and 20 Hz bands, the Hsu's output was
impressively high, bordering on scary -- enough, actually, to shake the
walls and almost everything attached to them.
Hsu's larger amplifier has a soft limiter that matches the capabilities of
the Hsu subwoofers, to minimize overload problems. With my amp, which has no
such limiter and is about twice the power of Hsu's larger one, I could
audibly overload the TN1220HO with I played bass-heavy recordings very, very
loud.
The larger Hsu amplifier (the new 500W unit) is designed to drive two
subwoofers in parallel. Although I didn't have a Hsu amp, I did have a
second TN1220HO. I therefore did some listening with both subwoofer set up
side by side, which increased the bass reserve quite significantly [should
be 6 dB]. At normal bass levels, the 1220s just coasted along, but on such
demanding program materials as pipe-organ pedal notes, they delivered
louder, deeper bass than any other subwoofers I had available. Two TN1220HO
subwoofers and a single Hsu amp would give you a very cost-effective
subwoofer system with very high output for less than $1,500.
The Hsu Research TN1220HO is distinctively different from most other
subwoofers. Its combination of slim tubular styling, light weight, small
footprint, high output down to the lowest frequencies, and very modest price
make the TN1220HO a winner. It does what a real subwoofer should do,
providing large amounts of butt-kicking bass, all the way down to the 15 Hz
region. It will please both the classical pipe-organ enthusiast and the rock
'n' roller. Still not enough output? Buy two -- they're inexpensive enough!
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TN1220HO
Howard Ferstler, Sensible Sound, No. 67
Testing: A subwoofer is actually easier to test than a full-range speaker,
because you do not have to worry about radiation patterns, dispersion,
imaging, etc. All the woofer has to do is to produce clean, decently low (or
in the case of deluxe models, extremely low) bass, at satisfactory volume
levels, and with minimum distortion. Also, subwoofer distortion is easy to
spot and it is easier to determine if one is emitting spurious noises during
test-tone sequences than it is to try to detect such anomalies in speakers
that cover the full audible bandwidth.
By the time I had received the TN1220HO for testing, the Velodyne F1800R II
I had recently purchased had been installed in my main system for two weeks,
and I was curious about how the Hsu would compare. So, I pulled out and
installed the Hsu in the same room corner. However, before pulling out all
the stops, I did a series of level matching adjustments (using my Audio
Control SA-3051 real-time analyzer, the upgraded version of the
well-regarded SA-3050) to get the main channels and the subwoofer working
properly together. The analyzer made this easy to do (serious enthusiasts
should consider getting a good one such as the 3051 or their somewhat
cheaper R-130 model) and when I had completed my work, I proudly noted that
the response curve and splice I obtained was nearly identical to what I had
previously accomplished with the F1800 with its quite different crossover
design. Then, I began to do my measurements of the subwoofer as a subwoofer.
Employing a series of low-bass test tones, I could find no significant
differences between the TN1220HO and the F1800RII over their operating
ranges. On 20-Hz tones, both systems were just about perfect up to very high
levels, with the Hsu maybe emitting a tad more very low-level spurious
noise -- noise that completely disappeared when moving more than a few feet
from either system. Indeed, various artifacts on bookshelves and hanging on
the walls around my 3,400 cubic foot listening room were making enough
vibration-induced noise on their own to mask any distortion-related
artifacts from either woofer. The Hsu's 20-Hz tuning design did highlight
one characteristic: At that frequency the Velodyne's cone was moving a
considerable distance (cleanly), while the Hsu's cone was hardly moving at
all. Nearly all the bass was coming from its port and when you got close
enough to the bottom of the enclosure, you can actually feel your pants
shaking from the pressure waves. Getting close to the Velodyne's cone
resulted in the same thing. Impressive.
Interestingly, the TN1220HO's abilities, according to its gifted designer,
are at their most limited at about 31.5 Hz, where the woofer driver must
produce more bass than the tuned port. To check this out, I ran a series of
output level comparisons between it and the F1800 at that frequency. As I
advanced the gain, I discovered that both systems could work their way up to
a clean 110 dB -- at which point both I and my conspicuously vibrating
listening room gave up. (I lack the near-suicidal courage of some woofer
testers, but Hsu assures me that the 1220 can hit 115 dB with the Hsu amp,
and do so from 18 Hz on up to any selected crossover point, with typical 8
or 9 dB of room gain taken into consideration). At that level, as was the
case with the F1800, the Hsu was the only piece of hardware in the room that
was not buzzing and shaking.
This is striking performance, particularly in light of Poh Ser Hsu's claims
about the woofer's supposed limitations at that frequency. I never went so
far as to see which system could play louder (as a dedicated materialist, I
have a constitutional aversion to abusing hardware), but both certainly
exceeded any volume limits I would require and both surpassed the output
capabilities of the 4 robust, 10" woofers in my two Allison IC-20,
main-channel systems.
Serious Listening: I am tempted to say that no self-respecting audio critic
should be without a Hsu subwoofer, because the models the company produces
allow one to lock into a reference standard, of sorts. However, there are
other good subs out there (witness the Velodynes tested elsewhere in this
issue), although I rather doubt that any in the TN1220HO's price category
can match the unit in terms of bang-for-the-buck performance.
I listened to the unit with a variety of potent, demo-grade-bass recordings,
including my Mendelssohn Organ Works favorite (Argo 414 420), Saint Saens
Symphony No. 3 (Philips 412 619), Alan Morrison at St. Philips Cathedral
(Gothic 49083), and John Rutter's Requiem (Reference Recording RR-57CD). I
also gave it a whirl with some video material, including new DVD recordings
of Glimmer Man and Stargate, as well as the usual laservideo presentations
of Jurassic Park and Terminator II. In addition, I auditioned a compact disc
that Hsu supplied along with the subwoofer: Virgil Fox playing selections
from Bach, Dupre, Widor, and others. I should note here that Hsu habitually
supplies a bass-demo disc of some kind with each woofer system that he ships
to a customer, a very nice touch. In fact, when Poh Ser Hsu ships you a
subwoofer, he also ships you a list of super-demo-grade bass CDs and LDs to
go shopping for, and I think we can assume that as he continues his
research, he will also begin to include DVDs on his list.
[A lengthy description of the CD]
Not just with this CD, but in every listening case, the TN1220HO performed
sensationally, producing huge amounts of low, very low, or ver-very-low bass
with musical material and impressive thumps with video foley sounds, with no
audible distortion of any kind that I could detect. The reproduced bass was
room filling, smooth, stable rattle free (except when the room itself began
resonating from the bass power), and just about all even the most astute
high end audio-video listener could ask for. I do not believe I need to go
into any more detail here, other than to say that as a cost-conscious item,
the Hsu is hard to beat -- and hard to beat when cost is no object either.
It is hard to believe that any other woofer taking up as much or less floor
space would be able to match its capabilities.
What to Choose: Clearly, the big Velodyne F1800 is a sensational woofer
also, but it cost more than twice what the Hsu woofer/amplifier combination
does, and that will mean a lot to some $ensible people. For some, the
Velodyne will be more suitable, simply because its size and shape might fit
better into some home-décor situations. Put it in a corner, stick a lamp on
it, make the connections and adjustments, and you are ready to go. However,
if the corner is rather far away, and there is not a lot of space in it
(assuming you have the necessary vertical space), the Hsu might be the best
bet. The Velodyne is better finished and slicker, but the Hsu's effortless
woofer behavior at 20 Hz is a plus. Even more importantly, the Hsu is
subjectively equal to the F1800 from an electro-mechanical-performance
standpoint, and that is certainly going to be important to a lot of people
who are willing to put up with the 1220's top-heaviness, lack of an
accompanying screen protector for the driver [which you can easily get from
Radio Shack], and amplifier turn-on/turn-off eccentricities [turn on/off
thumps which have been eliminated for some time - Howard had an early
sample].
Speaking of the amplifier, after auditioning the Hsu, I decided I had to
have the thing ("No self-respecting audio critic should be without a Hsu
subwoofer," remember!) but decided to pass on the amplifier [Note: he ended
up getting it later when he decided that the Velodyne needed the 24 dB/Oct
Linkwitz-Riley crossover of the Phase Coupled Activator]. I have a good
outboard amp of my own just sitting around (an old AudioSource Amp One that
can be bridged to 170 watts, and which includes a soft clipping circuit),
and also have a Phase Coupled Activator subharmonic synthesizer that
contains a Linkwitz-Riley crossover of its own (with 90 Hz hinge points)
that worked fine with the subwoofer. Consequently, I shipped the amp back to
Hsu and permanently installed the woofer in my smaller A/V system in another
part of the house. [Note: he ended up using the Phase Coupled Activator unit
with the Velodyne, and purchasing our amp to go with the woofer]. I could
have just as happily put the Hsu in my bigger system and moved the Velodyne
to the smaller one, but one of the biggest virtues of the Hsu, its small
footprint, more or less made it the default choice in the rather pinched
corner area of the smaller system's listening-viewing room.
Regarding cost, I should also note that the Hsu is $300 cheaper than the
Velodyne FSR-12 that I reviewed along with the F1800. Which to choose in
this case? Well, the Hsu can play louder -- of that there is no doubt.
However, up to its maximum level (which is still quite high [Note: easily 10
dB lower in the low bass]) the FSR-12 is audibly the equal of the Hsu (and
the F1800 as well) and if one's décor considerations require something
styled differently from the Hsu and the listening room is not too large, the
smaller Velodyne might be a rational choice. All three systems performed
pretty much equally up to their respective maximum levels, so a purchasing
choice may pretty much boil down to those required maximum levels, plus
placement/décor considerations, necessary cable runs, and the kind of deal
you can get with the Velodynes from your retailer. I can safely say that I
would have no problem living with any one of them.
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Hsu Research TN1225HO
Michael Fremer, Stereophile Guide to Home Theater, June 1998
[Introduction and description of product. Tested product is the TN1225HO
with the 150W amplifier.]
Placement for deep bass
For home-theater enthusiasts with dedicated rooms, the best place for the
subwoofer is where it generates the best bass. (Duh.) But that is often not
realistic in a living room environment. In my room, the only place for a
subwoofer is a particular corner. [This compromised the performance of our
sub - see manufacturer's comments] Fortunately, that corner is at the front
of the room in line with the monitor and front speakers; when I am reviewing
bass-shy mini-speakers, I can raise the crossover frequency and still get
good blend. Even more fortunately, that corner generates some of the best
bass in the room, and there is enough maneuvering space for me to move the
woofer away from the walls.
As Hsu's literature suggests, one convenient way to find out where any
subwoofer works best is to place it in your viewing position and walk around
the room while playing low-frequency test tones. As you walk around the
room, certain locations reinforce low frequencies while others suck them up
like a gigantic black hole. Some locations give you lots of "one-note" bass,
others give you reinforced but nuanced low-frequency reproduction. When you
reverse positions, putting the subwoofer where you were standing and
reclaiming your listening position, you should achieve the same performance.
If you can place the woofer where the bass is best in terms of both amount
and timbral accuracy, you're home. If not, find the compromise location that
works best. If one of those bass-sucking black holes occurs at your
listening position, you're not going to get good bass no matter how much you
spend on your subwoofer. Be sure to experiment with the continuously
variable phase control; sometimes, putting the bass out of phase with the
main signal boosts deep bass rather than attenuating it.
Hsu Research provides free placement counseling for purchasers of its
products. You supply the room dimensions, layout, listening position, and
potential subwoofer locations, and they'll give you optimum location and
crossover frequency.
Purrformance
Scratching-post looks or not, the Hsu TN1225HO is a fine performer,
producing prodigious amounts of genuine, window-rattling 25 Hz bass with
ease. In fact the sense of dynamic ease is the system's strongest suit. At
20 Hz, there's noise and little else [We never claimed that it would reach
down to 20 Hz. For that, get the TN1220HO or the 12Va]. That's how Hsu tuned
the system because there's not much bass below 25 Hz on most home-theater
program material.
I played all my usual low-bass suspects, including the aforementioned Close
Encounters and T2 as well as Space Jam, Glory, and many other LDs and DVDs.
While the Hsu is impressive at providing deep, room shaking bass for a very
reasonable price, it doesn't perform miracles. Even with the crossover set
to 40 Hz - the lowest setting - I was able to identify the sub's location
with greater ease than with any of the other subs I've had in the room. [I
talked to Mr. Fremer after his article was done and found out that he had
the spiked feet grounded to his hard floor. Due to the extremely
light-weight of our subwoofer and the extremely powerful driver, the feet
will buzz against the floor under such conditions, especially in the upper
bass. We have subsequently included a note in the instruction manual for
users to place the subwoofer on a throw rug or use rubber cups to isolate
the feet from hard surfaces to eliminate the buzz that would make the
subwoofer easy to locate.]
In Space Jams, for instance, when the caroon spaceship flies over the
baseball field, there's a tremendous deep bass component that the Hsu
handles with ease, but I could "hear" the bass coming from the unit [I wish
reviewers would call when they experience problems. If Mr. Fremer had
called, we could have the problem solved in seconds. We never received Mr.
Fremer's room layout either. Mr. Fremer's not the only one who noticed this.
Many subsequent users who did not read the manual before trying out the sub
have similar experience when they place the subwoofer's feet directly on a
hard floor. When they isolate the feet from the hard surface, the problem
disappears]. Frequencies at or below 40 Hz should not be directional; I
assume a higher-frequency resonance is giving away the location [actually,
feet buzzing].
Although the TN1225HO produces very deep bass when the saucer hovers over
Richard Dryfuss' pickup in Close Encounters, it doesn't do so with the
authority exhibited by some other subs. I kept wishing the sound would get
further "down" - not in frequency, necessarily, but in terms of tightness
and timbral solidity [See manufacturer's comments below for an explanation
for the lack of tightness and timbral solidity compared to the NHT he was
comparing to]
The Hsu certainly goes down deep without hesitation or distortion, but it
does not emit the sock or punch, and definition of some other subs I've had
in my living room - all of which are more expensive, of course. [We feel
that this is due to the buzzing feet and frequency response differences. See
manufacturer's comment section below] While I won't characterize the
TN1225HOs sound as "one-note", I didn't feel it conveyed upper-bass textures
and timbres quite as convincingly as some other subs I've auditioned,
especially when I combined it with satellite-type speakers. [Again due to
frequency imbalance and buzzing feet. See manufacturer's comments below]
For this reason, I think the Hsu is better suited as a "last-two-octaves"
subwoofer coupled with L/R speakers extending down to 40 Hz or so. Using it
with the floor-standing Ruark Prologue Ones (which extends down to 45 Hz,
+/- 3 dB) proved to be ideal. This combo gave me the best sound I've had in
my living room for both home theater and music reproduction, with the Hsu
subtly providing the foundation to what was already a musically rich
picture. [This is consistent with our speculation that our sub in the only
corner he has tried is too deep bass heavy. By using the sub only for the
deepest bass, he effectively can achieve a flatter bass balance and thus
achieve the best sound he have had in his room for both music and home
theater.]
Conclusion
Unpowered, the Hsu TN1225HO sells for a ridiculously low $350. If you have
a THX or Dolby Digital processor or receiver, the unit already includes a
built-in 24 dB/Oct subwoofer crossover at 80 Hz, so you can easily drive the
TN1225HO from any spare amp channel you have lying around. If you buy a
six-channel amp instead of a five-channel model, you're ready to add 25 Hz
bass for $350! That's a bargain any way you listen to it.
Add $225 for Hsu's 150W amp and you are powered and ready to go for $575 -
still a great bargain, given the high SPLs, low frequency extension, and low
distortion the system provides. I know of no other subwoofer priced so low
that gives you this kind of performance. [He would have rated it a lot
better if we had the chance to eliminate the buzz and frequency imbalance
problems!] The 150W amp includes a passive "soft clipping" feature that
filters out the high harmonics of a clipped signal if you overdrive the amp.
I never even come close in my small-to-medium listening room.
However, the less expensive amp does not include a high pass filter; if you
have bass-limited main speakers, you'll have to drive them full-range, which
is not the ideal thing to do. Hsu's more expensive and more powerful 250W
amp ($450) includes a 24dB/Oct high pass filter that might provide a more
effective sub/satellite blend than I was able to achieve with the smaller
amp. This brings the total system cost up to $800.
This is still reasonable, but now there's competition from NHT's SW2 pi
(among others), which also provide 25 Hz performance and 250W of power in a
smaller, more conventional package. In my room, the NHT package performed
better than the $575 TN1225HO/150W amp combo, but is that surprising? [With
the buzzing feet problem solved, and the deep bass excess corrected, I would
be very surprised if the $575 combo would not trounce the NHT] Given the Hsu
driver's prodigious power-handling capacity and enormous excursion, I'll bet
that the TN1225HO/250W amp combo puts on an impressive show in a big room.
In any case, subwoofer performance is room-dependent, and Hsu offers a
30-day money-back guarantee. If you're looking for deep, powerful,
low-distortion bass and you don't have deep pockets, I don't see how you can
go wrong auditioning the Hsu TN1225HO in your home-theater system.
Keith Lahteine
Dear Sirs : Your, various, announcements for HSU sub woofers, more than,
smacks of commercial spam . In order to be fair, perhaps, the mention of
some of the other, equally as valid, sub woofer drivers might be
appropriate . These, as well as HSU, are all manufactured in the U.S.A.
and seem to enjoy, at least, as much popularity .
These are all 12" drivers and seem to have similar parameters . The
one out the longest and still amongst the most popular is the N.H.T.
1259 . Next and probably the lest widely known is the Audio Concepts
SV-12 . Because Madisound in Wisconsin carries the NHT, exclusively, one
of their largest competitors, Parts Express, introduced a driver called
the Dayton "Titanic" . This diver is quite similar to the NHT 1259 and
is priced within 5$ . Last but, certainly, not least is the "Shiva" from
Avatar Audio . These three drivers are so similar that a blind fold
could be used to pick a driver for the subwoofer and still not,
seriously, effect the outcome . If the HSU was added into the mix a
winner would still be a toss up . It may boil down to the "Bose Method
of Success" . May the best marketing win .
Sincerely : Keith A. Lahteine