Ibanez CF7 Chorus/ Flanger

A forum devoted to mod, tips and suggestions for upgrading and rehousing your VERY CHEAP commercial stompbox to near boutique excellence.
Post Reply
User avatar
Skarrgus
Breadboard Brother
Information
Posts: 54
Joined: 05 Nov 2008, 22:18
Been thanked: 15 times
Contact:

Post by Skarrgus »

Schem:
http://www.ibanez.com/parts/2002_PARTS/ ... CF7-01.pdf

I'm wanting to rehouse this and make it true bypass, so I figured I'd see about some mods. Particularly, adding more depth or thickness to the chorus setting. Any other mods welcome, as well.
Also what kind of switches should I use for the modes?

I'll be putting this in a 1590DD-sized enclosure along with the Phase Modulator from the same series (no mods, I love the PM7 as-is) so space for extra knobs and switches won't be a problem.

Thanks

User avatar
Skarrgus
Breadboard Brother
Information
Posts: 54
Joined: 05 Nov 2008, 22:18
Been thanked: 15 times
Contact:

Post by Skarrgus »

Nevermind... Found what I was looking for.

User avatar
iwantmypie
Information
Posts: 41
Joined: 04 Nov 2007, 14:22
Location: Wilbraham, MA

Post by iwantmypie »

Skarrgus wrote:Nevermind... Found what I was looking for.
care to share your findings? i'd also be interested in any sort of info regarding rehousing and true bypassing ibanez 7 series pedals. thanks.
Use boost pedals

User avatar
Skarrgus
Breadboard Brother
Information
Posts: 54
Joined: 05 Nov 2008, 22:18
Been thanked: 15 times
Contact:

Post by Skarrgus »

iwantmypie wrote:
Skarrgus wrote:Nevermind... Found what I was looking for.
care to share your findings? i'd also be interested in any sort of info regarding rehousing and true bypassing ibanez 7 series pedals. thanks.
It was about which transistor to short to get it to always be "on"... Figured it out about a minute right after posting. I'm still working on the rehouse, though.
I'd still like some help getting a deeper chorus sound, though.

User avatar
slash555
Information
Posts: 26
Joined: 16 Jul 2009, 16:56
Been thanked: 1 time

Post by slash555 »

hi! i'm rookie in this stuff so...
i want to reduce pedal output level. it it slightly boosting signal when it's on, expecially with distortion in front.
here's shematic
CF7-01.pdf
(43.7 KiB) Downloaded 413 times
what should i change?

User avatar
ansil
Cap Cooler
Information
Posts: 491
Joined: 03 Mar 2009, 21:49
my favorite amplifier: my hughes and kettner blue 30r
Completed builds: 3 jcm 800 builds
4 vintage plexi builds
2 bogner ecstasy preamps [both for personal use]
10 marshall guvnor mods and builds
100 jungle kat boosts
too many penguin love's to count.
5 blues pearl purplexed
dozen tube screamer fulldrive whatever you call them variants

hell i can't type this long it will piss off people what can i say i have been doing mods on toyz appliances gear sex toyz computers and such for 27 years. i started when i was 6 taking stuff apart.
Location: cleveland tn
Has thanked: 15 times
Been thanked: 13 times
Contact:

Post by ansil »

r36 r43 are limiting resistors on the outputs. you can put a 5k trimpot there on each one and dial in your level of reduction. or you could put it as a pot to ground. this may affect the sound somewhat desolder the resistors add jumpers and try it out dial it in till you get it. they are like 2 bucks at rat shack

ed

User avatar
Dirk_Hendrik
Old Solderhand
Information
Posts: 4193
Joined: 03 Jul 2007, 08:44
Location: Old Amsterdam
Has thanked: 232 times
Been thanked: 887 times
Contact:

Post by Dirk_Hendrik »

A skight increase of R23 and R31 will help you better and will only alter the level when the pedal is engaged.
Sorry. Plain out of planes.

http://www.dirk-hendrik.com

User avatar
loylo
Breadboard Brother
Information
Posts: 63
Joined: 23 Jun 2011, 08:05
Has thanked: 12 times
Been thanked: 20 times

Post by loylo »

Hello mirosol,

It may be completely off topic, but not that much beacause I want to speack about another Ibanez flanger.
I just happened to buy a used CF7, and I came across your web page about this unit. And I can assure you that the mess with the 2 additional cas and the wiring on the solder side of the PCB is all original, as my unit looks completely identical to yours.

Cheers!

User avatar
loylo
Breadboard Brother
Information
Posts: 63
Joined: 23 Jun 2011, 08:05
Has thanked: 12 times
Been thanked: 20 times

Post by loylo »

Yeah, I mean CF7, although I know I'm off topic (sorry for that).

I was refering to this page:
http://mirosol.kapsi.fi/2013/11/ibanez- ... usflanger/

The only reason I mention this here is because I realized Mirosol is a FSB member with this topic while I just bought a used CF7 four days ago.

User avatar
tertiumsquid
Information
Posts: 1
Joined: 06 Apr 2013, 06:47
Been thanked: 1 time

Post by tertiumsquid »

Hate to bump a dead topic, but I recently acquired a CF7 pedal and also noticed that it boosted volume when enabled (by around 4db). Found this page and tried the suggestions here, but no go - raising R23 and R31 made no difference, and R36/R43 affect the bypassed volume as well. I did find a way though:

Looking at the schematic slash555 posted (and probing around with my scope) I found out a couple things. First, the pedal combines the bypassed signal with the modulated signal, both at the same amplitude as the input, meaning the output is slightly less than double the voltage of the input. Second, the bypassed signal is switched in and out with a mosfet, Q1, but the normal/wackd switch shorts it so that it's always coming through anyway, meaning that any gain reduction for the dry signal will also reduce the bypassed signal, and there's theoretically no way to reduce the output below unity. Third, the volume output in Wack'd mode is the same as the bypassed volume.

So how do you fix this if it's unfixable? Well, I ended up having to cut a trace to do it. The trace going from Q1 to the normal/wackd switch needs to be cut, and a 22k resistor added across the gap. That reduces the gain of the dry signal when the effect is on, but Q1 will short the resistor in bypass mode making it unchanged. To reduce the wet signal, I changed R18 from 2.2k to 12k (actually 12.4k since that's all I had, but the .4 should make no difference). Now the output volume is exactly the same as the bypassed volume

One caveat - the volume in Wack'd mode will be reduced now, though perceptively it doesn't sound like it's quieter to me.

So again, the fix is: cut the trace from Q1 to pin 5 of connector P53, put in a 22k resistor across that, and change R18 to 12k. See the attached photo for where to cut.
IMG_5142.jpg

User avatar
Manfred
Tube Twister
Information
Posts: 1937
Joined: 04 Apr 2009, 23:42
Has thanked: 1671 times
Been thanked: 1344 times

Post by Manfred »

I have drawn your modification into the schematic.
CF-7 mod.jpg
ibanez_cf7-1.pdf
(48.74 KiB) Downloaded 224 times

User avatar
fuzzbunny
Information
Posts: 46
Joined: 09 Jan 2012, 18:12
Has thanked: 59 times
Been thanked: 14 times

Post by fuzzbunny »

tertiumsquid wrote: First, the pedal combines the bypassed signal with the modulated signal, both at the same amplitude as the input,....
Second, the bypassed signal is switched in and out with a mosfet, Q1, ....
Thanks for sharing your findings..!

Aside from the volume reduction mod, if the "bypassed signal" (when mixed with the modulated) was switched off, would you now have a vibrato effect?

User avatar
oniriuss
Information
Posts: 1
Joined: 09 Sep 2023, 19:53

Post by oniriuss »

Skarrgus wrote: 23 Jan 2009, 20:14 Schem:
http://www.ibanez.com/parts/2002_PARTS/ ... CF7-01.pdf

I'm wanting to rehouse this and make it true bypass, so I figured I'd see about some mods. Particularly, adding more depth or thickness to the chorus setting. Any other mods welcome, as well.
Also what kind of switches should I use for the modes?

I'll be putting this in a 1590DD-sized enclosure along with the Phase Modulator from the same series (no mods, I love the PM7 as-is) so space for extra knobs and switches won't be a problem.

Thanks
HELLO.

Hello, I am new to the site, very good afternoon. Along with saying hello, I wanted you to help me with some images or schematics of how you did to be able to leave the truebypass pedal, I have a CF7 and I have problems with the on/off switch , I have changed it 3 times without good results.

Any info is very helpful

greetings

Jota M.
__________________

JotaEse Lutheria @jotaese.lutheria :shred:

Post Reply