HSU VTF-3 MK5 HP, VTF-15H MK2, Research ULS-15 MK2 User Manual

VTF-3 MK5 HP

Features

Subwoofer Manual

Variable Tuning Hybrid Technology.

w you decide how deep to play.”The large flared ports can be re-tuned with the flip of a switch and the

“No

addition or removal of a port plug(s). With support for five different operating modes, including ported and sealed
hybrid modes, this subwoofer offers state-of-the-art performance in virtually all rooms.

Custom built woofers.

“The end of featureless boom.” We design our woofers from the ground up to have exceptionally flat response
and low distortion, so you will hear clean and detailed bass not found in lesser subwoofers.

Powerful BASH amplifiers.

Our custom built amplifiers have ultra-high headroom, soft clipping, subsonic filtering, adjustable Q, and
class A/B output stage to provide extremely high fidelity, low distortion, and high output.

Flexible room placement.

The luxurious and smooth non-vinyl finishes, rounded corners and edges, and front-firing woofer and ports
allow for close placement next to listeners, in corners, and even inside built-in entertainment centers.

Connects to almost any system.

“Integration is easier than ever.” Thanks to modern receivers that use Dolby Digital, DTS, THX, or Bass
Management, you can connect the subwoofer to your system with one cable. If you have invested in a stereo­only system, integration is also simple thanks to true 24 dB/Oct. low pass filters.

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10. Protect the power cord from being

NO USER SERVICEABLE

PARTS ARE INSIDE.

walked on or pinched particularly at
plugs, convenience receptacles, and the
point where they exit from the apparatus.

11. Unplug this apparatus during
lightning storms or when unused for
long periods of time.

12. Refer all servicing to qualified service
personnel. Servicing is required when
the apparatus has been damaged in any
way, such as power-supply cord or plug
is damaged, liquid has been spilled or
objects have fallen into the apparatus, the
apparatus has been exposed to rain or
moisture, does not operate normally, or
has been dropped.

The lightning flash with arrowhead symbol within an equilateral triangle is intend­ed to alert the user to the presence of uninsulated “dangerous voltage” within the
product’s enclosure that may be of sufficient magnitude to constitute a risk of
electric shock to persons.

Le symbole éclair avec point de flèche à l’intérieur d’un triangle équilatéral
est utilisé pour alerter l’utilisateur de la presence à l’intérieur du coffret de “volt­age dangereux” non isolé d’ampleur suffisante pour constituer un risque d’éléc­trocution.

The exclamation point within an equilateral triangle is intended to alert the
user to the presence of important operating and maintenance (servicing) instruc­tions in the literature accompanying the product.

Le point d’exclamation à l’intérieur d’un triangle équilatéral est employé pour
alerter les utilisateurs de la présence d’instructions importantes pour le
fonctionnement et l’entretien (service) dans le livret d’instruction
accompagnant l’appareil.

Important Safety Instructions

1. Read these instructions.

2. Keep these instructions.

3. Heed all warnings.

w all instructions.

ollo

4. F

5. Do not use this apparatus
near water.

loth.

6. Clean only with dr

7. Do not block any ventilation
openings. Install in accor
the manufacturer's instructions.

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dance with

8. Do not install near an
such as radiators, heat registers, stoves,
or other apparatus (including amplifiers)
that produce heat.

9. Do not defeat the safety purpose of
the polarized or grounding-type plug.
A polarized plug has two blades with
one wider than the other. A grounding
type plug has two blades and a third
grounding prong. The wide blade or

ong ar

the thir
safety. If the provided plug does not fit
into y
for replacement of the obsolete outlet.

d pr

our outlet,

consult an electr

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e provided for your

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ician

ces

13. WARNING: To reduce the risk of fire
or electric shock, this apparatus should
not be exposed to rain or moisture and
objects filled with liquids, such as vases,
should not be placed on this apparatus.

14. To completely disconnect this
equipment from the mains, disconnect
the power supply cord plug from the
receptacle.

15. The mains plug of the power supply
cord shall remain readily operable.

TABLE OF

CONTENTS

UNPACKING . . . . . . . . . . . . . 3

PLACEMENT . . . . . . . . . . . . . 3

HOOKUP . . . . . . . . . . . . . . . . 4

VOLUME LEVEL . . . . . . . . . .5

CROSSOVER . . . . . . . . . . . . 5

FINE TUNING . . . . . . . . . . . . 5

TROUBLESHOOTING . . . . . . 7

REPAIR . . . . . . . . . . . . . . . . . .8

SPECIFICATIONS . . . . . . . . . 9

WARRANTY . . . . . . . . . . . . . .9

Set-Up

Step 1: Unpacking

f your room does not have carpeting, unpack the subwoofer on a throw rug or piece of carpeting to

I
avoid unwanted scuffing or scratching. If the subwoofer is too heavy, please ask for assistance. Find
the top of the box and open it. Holding the flaps open, roll the box over until it is upside-down. Lift
the box off.

Stop for a moment to inspect the protective bag for any rips or tears that may have occurred during
shipping. If there is damage to the subwoofer underneath, or if there are missing items, notify HSU
Research as soon as possible. We will help you find a solution.

Moving the subwoofer

If necessary, place the subwoofer feet on gliders or on a throw rug to move it into position.

Step 2: Placement

Placement is extremely important because it dramatically affects the bass quality. An optimally placed
subwoofer will be more powerful and will sound better than a poorly placed one. There are many
myths about subwoofer placement. For example, there is no need to center a subwoofer between the
left and right front speakers. Good subwoofers radiate bass in all directions and cannot be located in
the room by sound alone.

Important guidelines

• Always maintain at least 3 inches of clearance between the driver and ports on the front of the
subwoofer and nearby surfaces.

• Your subwoofer does not have magnetic shielding. Keep the subwoofer at least 5 feet away from
CRT type monitors. LED, LCD, Plasma, and DLP TVs are not affected, and the subwoofer can be
placed next to these items with no magnetic interference. Keep the subwoofer at least 4 feet away
from computer hard drives in order to prevent the hard drives from being erased.

3

Avoid placing the subwoofer

halfway between the front

and back walls. Avoid sitting

there as well.

Corner and nearfield

placement usually sound best.

Rules of thumb for placement

• Avoid the center of the room: In general, avoid placing the subwoofer half way between the front
and back walls. This is where you get a strong null from your room’s standing waves. You should
also avoid sitting in that area. No matter how powerful the subwoofer is, there will not be much
bass around the center of the room.

• Use corner placement: Subwoofers usually sound best tucked in a corner. A good corner is far from
wall divisions and has at least 6 feet of wall to either side. If you have more than one good corner, use
the one farthest away from large room openings or the one closest to the listener. Keep the subwoofer
within 1 foot of the wall.

• Use nearfield placement: A good subwoofer usually sounds best close to the listening position. As an
added bonus, the subwoofer’s volume level will be lower so neighbors are less disturbed. We strongly
recommend this method if your couch is up against the back wall and your room is over 18 feet deep.

• Use “subwoofer crawling”: This excellent technique is not as hard as it sounds. The room’s
acoustical reflections are used to your advantage. Place the subwoofer in the listening position, in
a seat, towards ear level. Connect the subwoofer to the system and play some music with steady and
constant bass. Walk around the room, listening for the nicest and most even bass. When the bass
sounds good, crouch down and listen where the subwoofer would normally be. You may use a SPL
meter to measure the evenness of the bass. Mark the best sounding place. The subwoofer should
be placed there.

• If you are using two subwoofers, place them side-by-side to maximize headroom, or separate them
to potentially smooth out in-room response.

• If you are not able to place the subwoofer in an ideal location, the subwoofer should be placed
within a foot of a wall for better bass.

• You may place a subwoofer inside a cavity in your entertainment center if one inch of space is main­tained around the back, top, and sides of the subwoofer. You may need to secure items in the cabinet
so they don’t vibrate. If you cover the front of the cavity, make sure it is acoustically transparent
– slatted, cloth, etc.

4

Moving the subwoofer

lways use two people to lift and move the subwoofer into place. Do not drag the subwoofer, as this can leave

A
streak marks on the flooring surface and scratch marks on the subwoofer. Screw on the rubber feet securely
before moving the subwoofer into place.

Step 3: Hookup

We will refer to receivers, integrated amplifiers, and preamps as controllers.

ake a look at the back of your controller. The output connectors available

T
determine the best method of hooking up your subwoofer.

Method A. Connecting to controllers

with a SUBWOOFER or LFE output

If you have this, you should use it. All Dolby Digital, DTS, THX, and Bass Management
equipped controllers have a low level SUBWOOFER or LFE output. It offers the easiest and
best connection. Run a cable from it to the subwoofer’s low level SUB-IN input. A standard
mono interconnect cable with RCA jacks on both ends can be purchased from electronics
and audio stor
When wiring, allow for an extra yard or two. The cables should lie flat with a little bit of
slack to give you some placement flexibility.

es. A special subwoofer cable is not needed, and neither is a Y-connector.

Set your controller to enable subwoofer output. To do this, go to the SPEAKER SET-UP or BASS
MANAGEMENT menu and set the SUBWOOFER to ON or YES. All the speakers should be set to
SMALL if possible. This directs the deep bass from the satellites to the subwoofer, freeing them and
their amplifiers from the rigorous demands of reproducing bass.

For older Dolby Pro-Logic controllers, your center channel must be switched to NORMAL instead of WIDE, or else the bass from the
center channel will not be fed into the subwoofer. For Dolby Digital controllers, go to the SPEAKER SET-UP or BASS MANAGEMENT
menu on your controller and turn the subwoofer to NO or OFF and set the left and right channels to LARGE.

Method B. Connecting to controllers

with HIGH LEVEL speaker outputs.

If your system does not have a SUBWOOFER or LFE output (for example, stereo-only
integrated amps or older Dolby Pro Logic receivers) you can use the HIGH LEVEL speaker
outputs. The subwoofer taps the signal from the controller’s amplifier, letting the subwoofer
reproduce the bass of the left and right channels. This method is also called bass augmentation.
Since the subwoofer uses its own amplifier there is no noticeable drain on your main amplifier.

You will need to run two lengths of two conductor speaker cable or zip cord. This wire is not
included with your subwoofer but can be purchased at electronic or home improvement stores.
Strip 1⁄2˝ of insulation from each end of the wire to expose the bare metal. If your speaker wire
is fraying, tightly twist the metal. Unscrew the plastic hex nut on the binding post to insert the
exposed wire into the hole. Tighten the binding posts by hand.

Run the wires from your system’s amplifier to the subwoofer’s HIGH LEVEL INPUTS. For each channel, run wire from the red (+) out­puts on the amplifier to the subwoofer’s red (+) inputs, and from the black (-) outputs on the amplifier to the subwoofer’s black (-) inputs.
Make sure the black amplifier outputs are “true ground.” Bridged outputs cannot be used.

Be sure to double check all connections for the correct polarity so that the positive (+) terminals go to positive (+) terminals and negative
(-) terminals go to negative (-) terminals. Most wire has some marker to help you keep track of the polarity, such as ribbing, color coding,

iting on one of the two strands. Tighten the binding posts by hand. If you prefer to terminate your cables, we recommend springy

or wr
banana plugs for a reliable connection. They are available from electronic and audio stores.

Method C. Connecting to controllers with PRE-OUTs.

If you do not have a SUBWOOFER or LFE output but have an extra PRE-OUT, you can use this instead of the speaker outputs. Run a
stereo RCA interconnect from your PRE-OUT to the left and right inputs on the subwoofer. For Dolby Pro-Logic controllers, your center
channel must be switched to NORMAL. For Dolby Digital controllers, the subwoofer must be switched to NO or OFF and the left and
right channels set to LARGE.

If your system (a) has a MAIN-IN connected with a metal jumper to a PRE-OUT
HSU High Pass Box for the added benefit of keeping the bass out of your speakers. Please contact HSU Research for details.

, or (b) you have an external amplifier, you can purchase our