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QTA Systems |
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| HI-Fi, Loudspeakers, Cabinets & Kits |

A high grade circuit for
producing a single low frequency output from Stereo Line Level inputs.
With modification to the filter block component values,
it can also substitute for a Low Pass Passive filter /
crossover in an existing system. Orders 1 through 4 are
available as is output gain. Strictly DIY on this, you do
your own thing.
# Provides high quality line
level LF output for sub woofer.
# Sums L + R Signals from Line or
Speaker Outputs.
# Buffered inputs with option of
180 degree phase reverse on one input.
# Single frequency operation,
(adjustable by component selection), with gain control.
# Option by component selection
of 1st to 4th Order filter.
# Timing delay circuit, seconds
to minutes for system settling. No pops
and
bangs at switch-on using a high quality signal relay.
# Buffered output.
# Options on signal chip set,
Standard (TL072 ) upgrade1 (TL052).
# Supplied pre-built, or with all
parts, documentation and hardware. Excludes power supply.
NOTES
(a) Supplied complete with pre drilled
black ABS case, PCB mounting hardware, phono
sockets, internal wire and power supply connector, but NOT power supply.
(b) Available with upper 3dB roll
off points @ 80, 100 or 120 Hz depending upon components.
Please specify when you order. If you don't specify
you get 100Hz, 4th Order, 24dB/ Octave.
(c) May be used to assist HF clutter
removal from Band-pass sub bass units or used
with full frequency range enclosures to restrict
upper frequency activity.
(d) This board does NOT drive a
Sub on it's own. You still need a Power Amplifier.
(e) Requires dual rail power supply,
unregulated (20 - 24)Volts per leg, DC input @ 50mA.
NOT Supplied. If you have a dual +/- 15 volt
supply available you can bypass the
front-end voltage regulators. Higher input voltages
can be accommodated with zener diode clamping.
| Order Code | Description | Options | Price GBP |
|---|---|---|---|
| SWLP1 | Low Pass Sub Woofer Filter. Pre-Built. Excludes Pwr Supply | Frequency, Order | 77.01 |
| SWLP2 | PCB Board, Circuit, Components. Excludes Power Supply | Frequency, Order | 63.10 |
| SWLP3 | PCB and Documentation only | ******** | 23.53 |
| UPGRADE OPTIONS | |||
| RSET1 | Extra set of 80 Hz filter parts | ******** | 2.67 |
| RSET2 | Extra set of 100 Hz filter parts. | ******** | 2.67 |
| RSET3 | Extra set of 120 Hz filter parts | ******** | 2.67 |
| CSET1 | Chip-Set Upgrade for SWLP1 or SWLP2 | ******** | 5.35 |
All Prices include VAT @ 20%. See buy it for further information.