lusithand DEVICES 800BMF Dual Stacked Preamp Plus Active Blend and Master Volume
Dual stacked preamp plus Active Blend and Master Volume
DESCRIPTION
The 800BMF preamp borrows the EQ section of the famous GK800RB amplifier and squeezes it into an onboard preamp while making it lower impedance through-out for quieter operation.
The 800BMF is a full version of the 800BM which includes an Active Blend control and Master Volume making this a fully active preamp.
(no passive operation possible)
Being a Boost-Cu 4 bandt preamp, the Hi-mid and Treble controls are highly interactive; same goes for the Lo-Mid and Bass controls and together with the Contour switch allows for a pallete of sounds at the tip of your fingers.
Another great feature is the ‘Contour’ switch which is accessible, on the 800BMF, via a push-pull switch on the Volume control.
The preamp is set for approximate unity gain and there is a Gain trimpot that allows for a little bit of boost on the overall audio signal.
An important feature of this preamp is the ability to choose how you want your stacked potentiometers to function since these have connector cables. It is up to you if treble goes on top or bottom of the potentiometer or if you want to pair the Hi-mid and Treble on one pot and Lo-Mid and Bass on the other, it is, ultimately, your choice.
The potentiometers are labelled “top” and “bottom” while, on the motherboard, “Hi-mid”; “Lo-mid”; “Treble” and “Bass” are also labelled for an easy and intuitive installation.
- Potentiometers: x2 dual concentric (10mm bushing height, 8mm ⌀) top = 6mm ⌀; bottom = 8mm ⌀ x1 Blend_6.35m ⌀ (use with 6.35mm knob) x1 Volume (with contour switch)_6.35mm ⌀ (use with 6.35mm knobs)
- Blend Board: 25 x 32.5 x 14mm
- Main Board: 27.5 x 57.6 x 12.5mm
Installation and Warranty: This is a solderless preamp. Any tampering with the preamp (ex: soldering or unsoldering directly on the preamp or any of its components) can result in Warranty void.
Installation Tips
When installing the smaller potentiometers, please make sure you create a solid base for these to sit on to prevent the pot from sinking into the wood (i.e use another washer between the potentiometer’s base and the wood of the instrument).
ºWhen puting the nut into the potentiometers, DO NOT FORCE these in. If necessary turn them around and give it another go and turn them gently.
ºFor proper function of the preamp, do not twist the provided cables as this can put stress on the connectors and create a bad contact.
- Treble: Boost and cut 4khz
- Bass: Boost and cut 60hz
- Volume + Contour: Pre-shape EQ (mid scoop) via push-pull switch
- Hi-Mid: Boost and cut 1khz
- Lo-Mid: Boost and cut 250hz
- Gain trim: Boost the overall audio signal
- Blend control: active blend
- Voltage: 9 to 27VDC Current
- Draw: +- 6mAh (9v)
GND: All ground connectors are equal. Feel free to use them as it best suits you. There are 7 in total so, make sure you connect all your parts that need grounding for proper circuit operaton.
Warranty and Conditions
Any of our products, that are defective, will be replaced/ fixed and all expenses will be covered once it has been verified that the problem isn’t a result of bad handling or negligence on the owners part. If the damage is due to negligence or wrong handling, warranty is lost and a cost can ocurr fior the devices repair (the shipping costs will not be covered on such cases).
Warranty is valid for 2 years after the date of purchase.
Documents / Resources
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lusithand DEVICES 800BMF Dual Stacked Preamp Plus Active Blend and Master Volume [pdf] Owner's Manual 800BMF Dual Stacked Preamp Plus Active Blend and Master Volume, 800BMF, Dual Stacked Preamp Plus Active Blend and Master Volume, Stacked Preamp Plus Active Blend and Master Volume, Preamp Plus Active Blend and Master Volume, Active Blend and Master Volume, Blend and Master Volume, Master Volume, Volume |