SKU: 65965059828
bass booster box

bass booster box Sadowsky Onboard Bass Preamp w/ Mid Boost

Sale price$22.80 Regular price$25.33
Save 10%

Pay in installments of $6.33 with ShopPay, AfterPay and Klarna

Shipping Estimate
USA
  • USA
  • CAN

Ships within 48 hours · Estimated delivery Jul 28 - Aug 2

Promo Codes Available:

For Your Every Summer RSVP, with Code: SUMMER15

Description

bass booster box Sadowsky Onboard Bass Preamp w/ Mid BoostSadowsky Onboard Bass Preamp with Mid Range Boost 4 Knob System Active w VTC SAC ELE OBOARD MB4K The Sadowsky Onboard Bass Preamp (4 Knob System) is a completely prewired system offering the same controls and the same legendary active preamp as all Sadowsky basses. This preamp is designed for installation on most J style basses with a metal control plate. On newer active J style basses with a side jack and a battery compartment, usually no

Sadowsky Onboard Bass Preamp with Mid Range Boost - 4-Knob System Active w/ VTC

SAC ELE OBOARD MB4K

The Sadowsky Onboard Bass Preamp (4-Knob System) is a completely prewired system offering the same controls and the same legendary active preamp as all Sadowsky basses. This preamp is designed for installation on most J-style basses with a metal control plate. On newer active J-style basses with a side jack and a battery compartment, usually no modification is required. On passive basses, the only required modification is to move the output jack to the side of the instrument and to make room for a battery.

The controls are: Volume – Pan (Balance) – VTC (Vintage Tone Control) – Treble / Bass – Mid Boost switch. The treble and bass controls are boost only - flat response is with the controls at their complete counterclockwise position. The preamp also features a 500 Hz mid boost that can be switched on/off with a toggle switch. The VTC control is passive, the maximum setting is a flat EQ. The further you turn the control down, the more the high end in the signal will be attenuated.

The preamp can be installed either with the included control plate or mounted through a rear control cavity in either a 4-in-line or diamond pattern. This system is not compatible with active pickups requiring anything else than a 250K or 500K volume or balance pot.


Sadowsky MB4K Onboard 4-Knob Bass Preamp Specifications: 
  • Prewired Onboard Bass Preamp w/ Mid Boost for Jazz style basses with a metal control plate or rear mounted controls
  • Right-Hand Orientation 
  • Active preamp for passive pickups
  • 4-Knob layout w/ Toggle Switch
  • Volume / Balance / Vintage Tone Control (P/P) / Treble Bass Stack / Mid-Boost Toggle
  • Push Pull function at VTC for Preamp Bypass
  • Included 0.1µF  replacement capacitor for the VTC module for improved treble roll-off when used with Sadowsky Soapbar Pickups
  • Frequency Response 5Hz - 50kHz
  • Bass: +18dB Boost @ 40Hz
  • Mid Boost: +10.6dB @ 500Hz
  • Treble: +18dB Boost @ 4kHz
  • Total harmonic distortion (THD) 0.18% at 1kHz
  • Power Supply via one 9v Battery
  • Current Draw 9mA
  • up to 870 hours battery life
  • input impedance 1Mohm
  • output impedance 1kohm

PLEASE NOTE:

  • Defects or damage resulting from culpable or improper installation as well as the use of unsuitable accessories or tools are excluded from the guarantee. This includes soldering points that are too hot, wrong soldering tin and the resulting damage to the electronics and soldering points.
  • When installing a Sadowsky Onboard Preamp on a MetroExpress bass without a control plate (Modern, Verdine White and M/J models), the holes in the body for the potentiometers must be enlarged. This is because the factory installed potentiometers on the MetroExpress have a smaller diameter than the potentiometers on the Sadowsky Onboard Preamp.
This preamp has screw down connectors for a solderless installation.  
Shipping Notes
  • Free Standard Shipping on $100+ Orders to the USA.
  • Except Preorder products are shipped in 48 hours.
  • Delivery to the USA:
  1. Standard Shipping : 3-10 business days
  • If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
  • We offer a 30-day return/exchange service after receiving.
  • Final sale items are not eligible for returns or exchanges.
  • To process your return/exchange, please contact us at [email protected]
  • Please click here for more details>>> Return & Exchange Policy
SKU: 65965059828

Discover Niche Categories That Outsell bass booster box

Top-Converting Item to Boost Your Average Order

4.2 ★★★★★
Based on 30 reviews
Sort
Highest Rating
Newest First
Oldest First
Product Reviews
L
Verified Purchase
laceyse
Boise, US
★★★★★ 5
Surprising good - great quality for price.
These are great for the price. They run a little wide in the waist so I sized down from an 8 to a 6 and they fit perfect. They are a true wide leg - so don’t buy if you are looking for something more straight leg or flair. The quality of the denim is very nice. I’m actually surprised and the quality. These do not feel stretchy which is good for the style. Very happy. Hopefully they hold up after washing
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on January 24, 2026
P
Verified Purchase
P French
Carnegie, US
★★★★★ 4
Very thick fabric
Special Size: Wide Leg Crop, Size: 8, Color: Black
Great quality. Would have been 5 stars, but the material is very thick and stiff. They do run small, but long. I ordered the 8, I’m 5 foot. They needed to be hemmed about 4 inches.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on March 19, 2026
I
Verified Purchase
ITSJUSTME
New York, US
★★★★★ 5
GET THESE JEANS!!
Special Size: Wide Leg Crop, Size: 12, Color: Iced Blue Light Wash, Special Size: Wide Leg Crop, Size: 12, Color: Iced Blue Light Wash
I ordered these jeans because they were recommended by a youtube influencer and I have 0 regrets! They are a fairly heavy denim with just the right amount of stretch to them. I'd consider them to be mid to high waisted since the closure is right below my belly button. However, if I hike them up a bit they sit right above the belly button. I washed and dried them with little to no shrinkage. Length-wise they're slightly cropped on me, and fall right above the ankle. These jeans are honestly SO versatile because they look great with ballet flats, heels, tennis shoes, AND suede or leather ankle boots! Since I couldn't decide, I ordered them in two colors (iced blue light wash & medium blue vintage), and I love them both!! For reference, I'm 5'6 and 170 lbs. I ordered size 12 and they fit great. Highly recommend. You CANNOT beat the price for this level of quality in my opinion!!
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on October 4, 2025
S
Verified Purchase
Suzanne Jones
West Palm Beach, US
★★★★★ 5
Perfect buy!
Fit Type: Regular, Size: Large, Color: White
This white denim jacket came today, and finally I bought the perfect jacket! It's actual denim, heavy but not too bulky. It fits perfectly, I bought a large, it's white not off white, and it is EXACTLY what I was looking for! I had to wait a week or two but it is definitely worth the wait! Beautiful jacket, well made and at a decent price! Thanks Amazon Essentials!
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on April 20, 2026
J
Verified Purchase
Just My 2 Cents
Fort Morgan, US
★★★★★ 5
Love denim and tired of cropped jackets?
Fit Type: Oversized, Size: Large, Color: Medium Blue Vintage
I like this a lot, it was what I was looking for as far as I'm so over everything you buy these days is cropped. Cropped styles are great, but are kind of getting old for some things in my opinion. The jacket is big as far as how it fits. I am 5'8" about 180 and I wish I would have got a medium, I got a large. The large is big and roomy enough that I could even wear ear a thick hoodie under it if I wanted to. However, the length is good as what I was looking for. The upper arms are large. However, this is a great quality denim jacket. Nice and thick, sturdy material (which I wanted). It's also at a great, competitive low price even if it's not on sale. Don't believe me, go ahead and search jean jackets. You'll see a ton, but I looked too and the quality did not look as good as this and plus the other jackets were a lot more for a lot less. If you're looking for a longer jean jacket, I highly recommend this. I'd say just think seriously about sizing down 1... even maybe 2 sizes. I would have gotten an XL before I read the other reviews. They recommended to size down, and after getting my jacket I could have sized down to a medium. I'm still happy with it and this is a jacket that is stitched well and will last a very long time. As always though, that's just my 2 cents. :)
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on January 19, 2026

recommand products