Harley Benton MJ4-MN Natural (modding + mini-review)
Nov 20, 2019 8:53:29 GMT
JAC and LeoThunder like this
Post by Michael on Nov 20, 2019 8:53:29 GMT
! This mod applies most probably to all Enhanced Series Basses, because the preamp is the same.
!! There will be of course bits of review upon the instrument, any questions can be asked, I can check and comeback with a response (I am a guitar tech so it's a plus)
I have bought myself an Enhanced Jazz Bass (4 string) in Natural finish, mostly for the pickup layout, MM style pickup in the bridge, and classic vibe-ish look (the stainless steel frets are a bonus).
The instant the bass arrived, I tuned it up and played it, very nice feel for the initial setup, lowered the action height, did a better intonation and that's it. The bow of the neck was perfect right out of the box.
After a half an hour of playing I proceeded to open up the control cavity, checked the rather simple complexity of the wiring (100% solderless connection to the preamp, the rest is solderless or soldered connections to the pots and split-coil switch, don't know about the jack input).
So this is the wiring layout (by the way, coil-tap is a wrong definition for splitting a pickup, it is correctly referred to as "coil-split(ting)".
My first thought was to search for this existing preamp, found on WSC Music site where you can buy them aftermarket. Checked the diagrams for other configurations as well, to my pleasant surprise the preamp board is 90% identical to most of the other configurations available (probably for cost-effectiveness).
My bet is that most of these preamps that came and will come with these Enhanced Bass versions from Harley Benton, will be the same on the preamp side.
So I saw another configuration but with the same preamp, the only addition was that it had a Mid control potentiometer. So the next idea came to my mind, if the preamp PCB's look the same, the MJ-4MN has only a 2-band EQ, the possibility to add a Mid control is very high. I proceeded to check the unconnected slots of the preamp. There are 3 unconnected connections (2pin x2 and 4pin x1, if I remember correctly).
Had laying around for a long time a 4pin JST type Molex connector, checked if it fits the empty 4pin male slot on the preamp, it fits perfectly so I went out and bought a 100K potentiometer (doesn't matter if it's linear or logarithmic, although the existing pots on the bass are all linear). Didn't find one with a center detent so I fitted it with a detentless B100K short split-shaft pot.
This is the connector that fits the preamp, in the picture above it's a 5pin JST Molex 1.25mm but the preamp needs a 4pin version.
Took out the neck pickup, soldered the MM style pickup directly to the Volume push-pull pot, wired up the B100K to the 4pin connector for Mid control.
Put everything back and for my utter amazement, I transformed the preamp into a 3-band EQ one.
So the pots are in the following order: Master Volume (push-pull passive/active) + stock Treble control + modded Mid control + stock Bass control (and the coil-split switch between the last two, for coil-splitting the humbucker).
The results are somewhat nice, having an onboard Mid control, it enables you to directly cut off the Mids, resulting in a resemblance of the MM Stingray tone with a Treble scoop setup. The only thing that is a bit out of place is the frequency at which the Mid control works when opened 100% (boosted), having a change in pitch and somewhat of a synth-like sound to it.
The complexity this mod requires:
Soldering skills to undo the neck pickup, and re-solder the bridge pickup directly to the Volume pot, or to the wires that go to the volume pot via the molex connector.
1 x JST Molex 1.25mm 4pin female connector (preferably with wires and with a minimum length of 10cm)
1 x B100K or A100K potentiometer (mono, not stereo)
and that's about it.
! for the wiring order of the connector to the Mid control pot, you can figure it out by looking at the existing Treble and Bass wirings.
With patience and some basic observation skills, this mod can be easily done for those who need a Mid control in their Enhanced basses.
Any questions are welcomed, will be replied to here, and if needed I can provide pictures from my preamp for future clarifications.
!! There will be of course bits of review upon the instrument, any questions can be asked, I can check and comeback with a response (I am a guitar tech so it's a plus)
I have bought myself an Enhanced Jazz Bass (4 string) in Natural finish, mostly for the pickup layout, MM style pickup in the bridge, and classic vibe-ish look (the stainless steel frets are a bonus).
The instant the bass arrived, I tuned it up and played it, very nice feel for the initial setup, lowered the action height, did a better intonation and that's it. The bow of the neck was perfect right out of the box.
After a half an hour of playing I proceeded to open up the control cavity, checked the rather simple complexity of the wiring (100% solderless connection to the preamp, the rest is solderless or soldered connections to the pots and split-coil switch, don't know about the jack input).
So this is the wiring layout (by the way, coil-tap is a wrong definition for splitting a pickup, it is correctly referred to as "coil-split(ting)".
My first thought was to search for this existing preamp, found on WSC Music site where you can buy them aftermarket. Checked the diagrams for other configurations as well, to my pleasant surprise the preamp board is 90% identical to most of the other configurations available (probably for cost-effectiveness).
My bet is that most of these preamps that came and will come with these Enhanced Bass versions from Harley Benton, will be the same on the preamp side.
So I saw another configuration but with the same preamp, the only addition was that it had a Mid control potentiometer. So the next idea came to my mind, if the preamp PCB's look the same, the MJ-4MN has only a 2-band EQ, the possibility to add a Mid control is very high. I proceeded to check the unconnected slots of the preamp. There are 3 unconnected connections (2pin x2 and 4pin x1, if I remember correctly).
Had laying around for a long time a 4pin JST type Molex connector, checked if it fits the empty 4pin male slot on the preamp, it fits perfectly so I went out and bought a 100K potentiometer (doesn't matter if it's linear or logarithmic, although the existing pots on the bass are all linear). Didn't find one with a center detent so I fitted it with a detentless B100K short split-shaft pot.
This is the connector that fits the preamp, in the picture above it's a 5pin JST Molex 1.25mm but the preamp needs a 4pin version.
Took out the neck pickup, soldered the MM style pickup directly to the Volume push-pull pot, wired up the B100K to the 4pin connector for Mid control.
Put everything back and for my utter amazement, I transformed the preamp into a 3-band EQ one.
So the pots are in the following order: Master Volume (push-pull passive/active) + stock Treble control + modded Mid control + stock Bass control (and the coil-split switch between the last two, for coil-splitting the humbucker).
The results are somewhat nice, having an onboard Mid control, it enables you to directly cut off the Mids, resulting in a resemblance of the MM Stingray tone with a Treble scoop setup. The only thing that is a bit out of place is the frequency at which the Mid control works when opened 100% (boosted), having a change in pitch and somewhat of a synth-like sound to it.
The complexity this mod requires:
Soldering skills to undo the neck pickup, and re-solder the bridge pickup directly to the Volume pot, or to the wires that go to the volume pot via the molex connector.
1 x JST Molex 1.25mm 4pin female connector (preferably with wires and with a minimum length of 10cm)
1 x B100K or A100K potentiometer (mono, not stereo)
and that's about it.
! for the wiring order of the connector to the Mid control pot, you can figure it out by looking at the existing Treble and Bass wirings.
With patience and some basic observation skills, this mod can be easily done for those who need a Mid control in their Enhanced basses.
Any questions are welcomed, will be replied to here, and if needed I can provide pictures from my preamp for future clarifications.