Boss SD-1 (Super Overdrive) Modification

Postingan hari ini saya coba men-share pengalaman saya nge-modif beberapa pedal saya, seperti Jim Dunlop GCB95, Boss CS3 dan Boss SD-1. Untuk sekarang saya share yang Boss SD-1 (Super Overdrive) dulu, pedal lainnya menyusul... ada beberapa versi modifikasi yang populer, seperti ke Ibanez TS9/TS808 atau MXR ZW44, tapi saya coba nge-mod versi saya sendiri dengan menggunakan part-part terbaik yang bisa saya dapatkan. Pedal ini saya modifikasi dengan bantuan teman saya Faisal.

My own version:

How to make SD1 Boss super overdrive sounds the way it should be! i like it a lot!!! There are only 7 things to do as i did some experiments, took me hours!!! this sounds better than any tube screamer to my ears...

• remove clipping diode at D6, and make a jumper (menjadi symmetrical clipping)
• connect any of one of these three caps, a 47pf or 51pf or 56pf cap in parallel with the clipping diode at D5 (sound drivenya gak terdengar "becek", it sounds really smooth and rich)
• remove the cap at C6, just leave it no need any jumper (more headroom)
• remove the electrolytic cap at C10 (1uF), and replace it with a 10uF electrolytic cap. (makes the tone clear and full)
• remove the resistor at R16 (1k), and replace it with a 470 ohm resistor. (TS9 attitude, but a lot more balls alias jantan sounding)
• R2 ganti pake 620k
• C2 ganti pake 1uF non polar

Ibanez TS9/TS808 Spec:

• remove clipping diode at D6, and make a jumper
• connect a cap 51pf in parallel at the clipping diode at D5
• R1 ganti pake 1k
• R7 ganti pake 1k
• R2 ganti pake 510k
• R4 ganti pake 10k
• R5 ganti pake 51k
• R8 ganti pake 220 ohm
• R9 ganti pake 1k
• R10 ganti pake 1k
• R12 ganti pake 510k
• R18 ganti pake 10k
• R19 ganti pake 10k
• C1 ganti pake 0.020uF
• C2 ganti pake 1uF non polar
• C4 ganti pake resistor 10k (antara C7 dan R4 dipasang capacitor ukuran 0.22uF dan jatuhnya ke ground, coba lihat skema TS9 baik2)
• C5 ganti pake 0.22uF
• C8 ganti pake 0.1uF
• C10 ganti pake 10uF
• IC ganti pake JRC4558D
• for TS9 specs R16 ganti pake 470 ohm resistor, R17 gak usah diapa2in
• for TS808 specs R16 ganti pake 100 ohm, R17 ganti pake 10k potensio drive ganti pake 500k logarithmic (kaki 2 dan 3 dipisah, berarti kaki 3 tidak tersambung)
• potensio level ganti pake 100k linear
• potensio tone gak usah diganti
• Transistors buat Q5 dan Q6 ganti pake 2N3904 atau 2N5088 atau 2SC1815. Kalo Tube Screamer memang dari dulu pake yg 2SC1815, cuma kalo gak dapet yahh pake aja yg sudah tercantum diatas, it will still sound the same. Check dulu Hfe nya supaya gainnya betul2 sama dengan spek Tube Screamer yang semestinya!
• Q5 between 460-470
• Q6 between 420-430
• Diode 2 biji ganti pake 1S1588 (kalo ada yg bisa dapet yg ini berarti that's the exact diode yg dipake di pedal TS9/808 era thn 1980an, 1S1588 susah banget nyarinya!!!) atau MA165 (reissue). Gak usah diganti juga gak apa2. Pake 1N4148, IN916, atau 1N914 it will still sound the same

MXR ZW44 Spec:

• Remove one leg of the resistor 33K (R5) that goes with 4K7 (R6) and connect to the diode's leg (D4) that goes to pin 7 at the opamp chip. Remove yellow wire #4 at the PCB and also remove red wire # 2. Connect yellow wire at # 2, # 4 stays EMPTY. Connect red wire to where the 33K resistor's leg used to stay that connects with the resistor 4K7 at R6, now this automatically goes to the opamp at pin 6
• Replace C4 with a 0.047uF capacitor
• Replace C5 with a 0.047uF capacitor
• Replace R3 with a 22K resistor
• Replace C7 with a 3.3uF capacitor
• Remove Q6, R15, R16, R17, R12, C8, and C10. These no need jumpers. The white wire # 12 at the PCB must be removed and has to be connected into the hole of C8 where the hole connects with R14
• Change Q5 with MPSA14 transistor. This is optional

*Note: setelah remove Q6, R15, R16, R17, and C10....try removing also R12 and C8. These

no need jumpers. The white wire that you already connect into the hole where the

base pin of Q6 used to stay, try pull that wire from that hole and connect it into the

hole of C8 where the hole connects with R14. Also the brown wire that was in hole

#1 is now connected to the ground (ini masalahnya kenapa gak mau bypass), pull it

out from the ground and connect it back into hole #1.

Sumber: http://ghanihilman.blogspot.com