BTB-MMSR 4 Knob 3 Band

Pre-Installation Test Setup

Verification Steps

After completing the test setup, verify the following:

• Audio signal passes through the preamp with no distortion or excessive noise
• All controls respond smoothly without crackling or cutouts
• Bass control provides both boost and cut functions
• Treble control provides both boost and cut functions
• Mid controls (level and frequency) operate correctly
• Battery connection is secure and provides adequate power
• No ground loop hum or excessive noise

General Installation Instructions

1. If necessary, remove the old electronics leaving the pickup wires, and any others, such as ground and battery wires, with plenty of length.
2. The single pots are marked: V = Volume, B = Bass, T = Treble
3. The pot threads are 7.0mm size. Fit them into their holes leaving the rubber spacer rings in place if the holes are the original larger size. Tighten them once they are in place.
4. The bass/treble circuit board can be left floating. Or, depending on the installation, it may be fixed to an appropriate surface, using the the sticky foam pads. It may be possible to fix it to the reverse side of the mid sweep circuit board, once installed.
5. Mount the mid sweep stack in the hole used previously for the mid pot.
6. Mount the pre-wired jack on its plate or swap the wires to the original jack, making sure they are in the correct sequence.
7. Connect the pickups wires to the bass/treble circuit board, according the the BTB-MM diagram.
8. A battery clip is provided with the preamp allowing it to be powered directly. But most basses will have a separate battery compartment. In which case, cut off the battery clip and join the red and black wires from the preamp to those in the bass. Before joining the wires, slip the heatshrink sleeves over the wires. After the joints have been made, the sleeving should be slid over the joints and heated with a hot soldering iron, or other localised heat source, held in close proximity. (The heatshrink sleeves can be found threaded on the black ground wire)
9. Connect the black ground wire from the jack to any ground wires in the bass, such as the one to the bridge.
10. Once all is proven to be working correctly, fit the knobs to their appropriate shafts, and refit plate.

Knob Installation

Circuit Board Connections

Refer to the circuit diagram for proper connections:

• HOT: Pickup hot wire
• COLD: Pickup ground/cold wire
• GREEN: Ground (GND)
• YELLOW: Output (O/P)
• RED: 9-18V positive (+VE)

Technical Specifications

Control	Specification	Notes
TREBLE	+20dB / -16dB @ 10 kHz	More boost than cut, giving rise the characteristic ‘sizzle’ associated with the Stingray® style of EQ
BASS	+14dB / -7dB @ 40Hz	The bass control has a little more boost than the original. The boost curve continues to rise towards the lower frequencies, without flattening out at any frequency within the normal bass guitar range. Conversely the cut characteristic is shelving, having an essentially flat response from 30 – 100Hz, when fully cut.
MID LEVEL	+/-12dB Boost/Cut	The upper knob sets the amount of Mid boost or cut at frequencies according to the setting of the Frequency knob. The midway indent is the ‘flat’ setting.
MID FREQUENCY	100Hz – 1kHz or 200Hz – 2kHz	The lower outer ring sets the continuously variable Mid frequencies for boost or cut. DIL switches on the circuit board allow low or high ranges to be set. Both switch sections should be set to ON for the Low Range and both set to OFF for the High Range.
POWER	9-18 Volts DC	This unit can be powered from 9-18 Volts DC.

MID SWEEP 01 Module

The MID SWEEP 01 is a stand-alone mid control which can be used on its own or cascaded in conjunction with other modules, including additional MID SWEEP 01s. The sweep frequency band is switchable, via DIL switches on the circuit board, between two overlapping ranges.

MID LEVEL & FREQUENCY

BOOST/CUT (+/-12dB): The upper knob sets the amount of Mid boost or cut at frequencies according to the setting of the Frequency knob. The midway indent is the ‘flat’ setting.

FREQUENCY (100Hz – 1kHz or 200Hz – 2kHz): The lower outer ring sets the continuously variable Mid frequencies for boost or cut. DIL switches on the circuit board allow low or high ranges to be set. Both switch sections should be set to ON for the Low Range and both set to OFF for the High Range.

Volume Control Configuration

Sets the level from the bass and treble section of the preamp feeding the mid section. This means that the pickup feeds the preamp directly, allowing the best possible transfer of signal, and full interaction of the pickup with the preamp. Since the mid section is after the volume control, it feeds the jack directly with a low impedance output.

Control Functions

VOLUME

Sets the output level from the preamp. Controls the signal level before it reaches the mid section.

BASS

Controls low frequency content with +14dB boost and -7dB cut at 40Hz. The boost curve continues to rise towards lower frequencies without flattening within the normal bass guitar range. When fully cut, provides essentially flat response from 30-100Hz.

MID LEVEL & FREQUENCY (Stacked Knob)

Upper Knob (MID LEVEL): Provides +/-12dB of boost/cut at the frequency set by the lower knob. The midway indent is the ‘flat’ setting.

Lower Outer Ring (FREQUENCY): Continuously variable control that sets the frequency for the mid boost/cut. Two ranges available (selectable via DIL switches on circuit board): 100Hz-1kHz or 200Hz-2kHz.

TREBLE

Controls high frequency content with +20dB boost and -16dB cut at 10kHz. Features more boost than cut, creating the characteristic ‘sizzle’ associated with Stingray® style EQ.

Frequency Range Selection

The mid frequency range is selectable via DIL switches on the circuit board, allowing customization for different playing styles and tonal preferences.

Care & Safety

• This unit does not contain any user-serviceable parts. Any repairs or maintenance should be carried out by qualified personnel only.
• Do not allow this unit to get wet or expose it to damp conditions.
• Do not leave a battery connected to the unit for extended periods if not in use.

Guarantee

• Your East product is guaranteed to be free from defects in materials and workmanship for a period of one year from the date of original purchase.
• If during the guarantee period your product becomes faulty due to defective materials or workmanship then the unit will be repaired or replaced without charge for parts or labour at the discretion of East UK according to the conditions below.

Conditions

1. The original sales invoice or receipt indicating the date of purchase and sales outlet is presented together with the faulty unit.
2. The unit was installed competently consistent with the instructions supplied.

What Is Not Covered

1. Damage due to accident or improper handling, installation or operation.
2. Defects caused by the instrument or system to which to which the unit has been installed.
3. Damage resulting from repair of the unit carried out by non-authorised service personnel.
4. The costs of transport or shipping costs relating directly or indirectly to the guarantee of this product.

Disposal Information

• Check Local Rules: Find out if there are any specific laws in your area about disposing of electrical waste.
• Recycle: Take your old preamp to a local recycling centre.
• Donate: If your preamp still works, consider donating it to a bassist who has yet to discover the wonders of our active bass technology!