Behringer - Vintage Phaser VP1 - True Bypass Mod

A forum devoted to mod, tips and suggestions for upgrading and rehousing your VERY CHEAP commercial stompbox to near boutique excellence.
User avatar
rasta_maleek
Resistor Ronker
Information
Posts: 258
Joined: 11 Jul 2009, 12:56
Has thanked: 52 times
Been thanked: 52 times

Post by rasta_maleek »

JiM wrote:I'm also interested in mods for this phaser. It's indeed a Small Stone clone, but there are some small differences with the schematic widely available. I've traced it, i still need to draw a clean schematic before posting it here.

I've done the Univibe-cap-ratio mod, with a 4PDT switch, and the result is not as dramatic as it is with a Phase 45.
http://www.lynx.bc.ca/~jc/pedalsSmallStone.html
But maybe it's because i messed with SMD-desoldering, delaminating some solder pads :( Still working but ugly :mrgreen:
I intend to make it true-bypass with the original DPDT switch, and an LFO-controlled Millenium Bypass.

As for intensity, you'd want to replace the "color" switch with a pot, i.e. vary the amount of feedback.

Some ideas :
http://www.moosapotamus.net/THINGS/frankenstone.htm
http://www.generalguitargadgets.com/ind ... &Itemid=26
http://sounddiy.free.fr/smallstone.html (in french, but the layout and sound samples are international ! Shows a "DEPTH" pot)

Here are a couple gutshots (before mods) ...
thanks for the job Jim, and for the schem.

:applause: :applause:

User avatar
sneakinhysteria
Information
Posts: 3
Joined: 04 May 2011, 20:32

Post by sneakinhysteria »

Hi all,

just successfully finished the VP1 rehousing and true bypass project, here is the story:

https://formleadsfunction.wordpress.com ... ou-fix-it/

Many thanks for the info and the schemes, they absolutely enabled me to start out in the first place!

Glad It still works, it was my first job of this kind. So happy with my custom phaser :)

User avatar
quackhandle
Information
Posts: 1
Joined: 05 Sep 2011, 08:33

Post by quackhandle »

soulsonic wrote:Okay, VP-1 True Bypass Mod pics are reposted here:
members/soulsonic/Gallery/BehringerVP1/
Hi Soulsonic, am very interested in doing this but getting 'page not found' error with the images. Are they anywhere else?

Cheers,

Quackhandle

User avatar
theblackman
Resistor Ronker
Information
Posts: 250
Joined: 27 Jun 2007, 00:43
Location: Western Australia
Has thanked: 10 times
Been thanked: 3 times

Post by theblackman »


User avatar
Bside2234
Resistor Ronker
Information
Posts: 260
Joined: 30 Jul 2007, 19:35
Location: Kennewick, WA
Has thanked: 10 times
Been thanked: 89 times

Post by Bside2234 »

Just picked up one of these today for $23 shipped. Great deal.
Anyway. Opened it up and they are using the Cool Audio V13700M now. 3 of them.
Here's a bad pic because it's just too dark right now.
IMG_20120106_202718.jpg

User avatar
JiM
Diode Debunker
Information
Posts: 967
Joined: 11 Mar 2008, 22:56
Completed builds: Completed builds :
Proco Rat
MXR MicroAmp in a volume pedal
TubeDriver (w/ NoS russian tube and big muff tone contol) + Phase 45 (w/ univibe cap ratio)
Dallas Rangemaster (w/ noisy OC75, negative ground)
SubCaster tube booster (w/ NoS russian tube, PtP)
Hot Harmonics
Music From Outer Space SubCommander in progress
Crackle Not OK
Simple bass blender in a 1590A
Bazz Fuss with a photo-darlington
Location: France
Has thanked: 70 times
Been thanked: 66 times
Contact:

Post by JiM »

Bside2234 wrote:Opened it up and they are using the Cool Audio V13700M now. 3 of them.
This means a spare OTA ! :thumbsup
I only give negative feedback.

User avatar
Bside2234
Resistor Ronker
Information
Posts: 260
Joined: 30 Jul 2007, 19:35
Location: Kennewick, WA
Has thanked: 10 times
Been thanked: 89 times

Post by Bside2234 »

I started tracing through it last night using the schematic JIM provided. 99% of the component reference is different but a lot of the values are the same so far. I pretty much stopped at the phase shifting stages and the IC for the LFO. I think some of the LFO circuit has changed and my eyes just got too tired to look at the phase shifting stages. Hat's off to JIM for tackling this.
"There's lots of track "stitching", it's quite hard to reverse-engineer"
No kidding. This thing goes back and forth with vias all over the place. The blue solder mask and all the silk screening doesn't help either.

User avatar
pinkjimiphoton
Transistor Tuner
Information
Posts: 1242
Joined: 12 Sep 2010, 19:03
my favorite amplifier: my own, a redesigned princeton
Completed builds: so fucking many goddamn pedals it would make your ass hurt just looking at 'em all!!!!!
there's videos that totally suck of about 90 of 'em here:
http://youtube.com/666pinkster
gimme a like: http://facebook.com/pinkjimiphotonrocks
Location: new world order land (formerly la-la land)
Has thanked: 358 times
Been thanked: 479 times
Contact:

Post by pinkjimiphoton »

brother soulsonic,
any chance you could re-up the pics?
thanks my friend...
namaste
"When the power of love overcomes the love of power the world will know peace."
Slava Ukraini!

User avatar
Scruffie
Opamp Operator
Information
Posts: 1739
Joined: 13 Mar 2009, 17:59
Location: UK
Has thanked: 28 times
Been thanked: 170 times

Post by Scruffie »

pinkjimiphoton wrote:brother soulsonic,
any chance you could re-up the pics?
thanks my friend...
namaste
:thumbsup

User avatar
pinkjimiphoton
Transistor Tuner
Information
Posts: 1242
Joined: 12 Sep 2010, 19:03
my favorite amplifier: my own, a redesigned princeton
Completed builds: so fucking many goddamn pedals it would make your ass hurt just looking at 'em all!!!!!
there's videos that totally suck of about 90 of 'em here:
http://youtube.com/666pinkster
gimme a like: http://facebook.com/pinkjimiphotonrocks
Location: new world order land (formerly la-la land)
Has thanked: 358 times
Been thanked: 479 times
Contact:

Post by pinkjimiphoton »

thanks scruffie!! :applause: :applause: :applause: :thumbsup
"When the power of love overcomes the love of power the world will know peace."
Slava Ukraini!

User avatar
revgunn
Information
Posts: 2
Joined: 28 Apr 2012, 07:20

Post by revgunn »

Any ideas on what to do about the volume drop?

User avatar
Binuts
Information
Posts: 6
Joined: 05 Jul 2012, 09:51

Post by Binuts »

revgunn wrote:Any ideas on what to do about the volume drop?
Yes please ! The French page talks about the R10 resistor http://sounddiy.free.fr/smallstone.html
I found an R10 in my VP-1 of course, but it's 30k and the most annoying is that it's a strange resistor, I'm a novice and I counted 8 legs around the little resistor…

I would be so glad to fix the volume drop ! Thanks

User avatar
JiM
Diode Debunker
Information
Posts: 967
Joined: 11 Mar 2008, 22:56
Completed builds: Completed builds :
Proco Rat
MXR MicroAmp in a volume pedal
TubeDriver (w/ NoS russian tube and big muff tone contol) + Phase 45 (w/ univibe cap ratio)
Dallas Rangemaster (w/ noisy OC75, negative ground)
SubCaster tube booster (w/ NoS russian tube, PtP)
Hot Harmonics
Music From Outer Space SubCommander in progress
Crackle Not OK
Simple bass blender in a 1590A
Bazz Fuss with a photo-darlington
Location: France
Has thanked: 70 times
Been thanked: 66 times
Contact:

Post by JiM »

Binuts wrote:I found an R10 in my VP-1 of course, but it's 30k and the most annoying is that it's a strange resistor, I'm a novice and I counted 8 legs around the little resistor…
The part numbers are likely to be different on a different board layout.
It happens that both R10 in Tonepad schematic and mine are for the same resistor, but this is merely a coincidence. The newer layout of the VP-1 is probably different, the only sure way to identify a component is to follow the signal path on both the schematic and the board.

The SMD resistor chips with eight pins are actually four resistors side-by-side in the same package. It saves board space, but it's less DIY-friendly.

Image
(this one has five)
I only give negative feedback.

User avatar
Binuts
Information
Posts: 6
Joined: 05 Jul 2012, 09:51

Post by Binuts »

All right thanks. Yeah I concede it's a fortunate coincidence, I was sure they copied the schematic of the small stone.
If there is no way to fix the thing directly, maybe you have an option ? (other than trash the pedal, i'll fix the bypass thing when i buy a 3pdt soon). It's too bad I can't mod something like that :(

Thanks anyway !

User avatar
JiM
Diode Debunker
Information
Posts: 967
Joined: 11 Mar 2008, 22:56
Completed builds: Completed builds :
Proco Rat
MXR MicroAmp in a volume pedal
TubeDriver (w/ NoS russian tube and big muff tone contol) + Phase 45 (w/ univibe cap ratio)
Dallas Rangemaster (w/ noisy OC75, negative ground)
SubCaster tube booster (w/ NoS russian tube, PtP)
Hot Harmonics
Music From Outer Space SubCommander in progress
Crackle Not OK
Simple bass blender in a 1590A
Bazz Fuss with a photo-darlington
Location: France
Has thanked: 70 times
Been thanked: 66 times
Contact:

Post by JiM »

They did somewhat copy the schematic, but they did not copy the layout (which would be copyright-protected).
You can definitely perform this mod, you just have to find your way in the layout by using the schematic as a map. That's much easier not to get lost when you have a map !
I only give negative feedback.

User avatar
Scruffie
Opamp Operator
Information
Posts: 1739
Joined: 13 Mar 2009, 17:59
Location: UK
Has thanked: 28 times
Been thanked: 170 times

Post by Scruffie »

Binuts wrote:All right thanks. Yeah I concede it's a fortunate coincidence, I was sure they copied the schematic of the small stone.
If there is no way to fix the thing directly, maybe you have an option ? (other than trash the pedal, i'll fix the bypass thing when i buy a 3pdt soon). It's too bad I can't mod something like that :(

Thanks anyway !
When you mod it for true bypass with the 3PDT, add a LPB-1 circuit or simmilar at the output to boost it, that's what im gunna do.

User avatar
Binuts
Information
Posts: 6
Joined: 05 Jul 2012, 09:51

Post by Binuts »

JiM wrote:You can definitely perform this mod
Well I don't see how I can solder or remove something like that with regular tools… :hmmm: can you tell me more about that type of work please ?
Scruffie wrote:When you mod it for true bypass with the 3PDT, add a LPB-1 circuit or simmilar at the output to boost it, that's what im gunna do.
Seems an easy way to fix the problem, this one should work http://www.musikding.de/Kits/Musikding- ... ::616.html but once again it needs some work to find how to plug it properly :lol:

User avatar
Scruffie
Opamp Operator
Information
Posts: 1739
Joined: 13 Mar 2009, 17:59
Location: UK
Has thanked: 28 times
Been thanked: 170 times

Post by Scruffie »

Binuts wrote:
JiM wrote:You can definitely perform this mod
Well I don't see how I can solder or remove something like that with regular tools… :hmmm: can you tell me more about that type of work please ?
Scruffie wrote:When you mod it for true bypass with the 3PDT, add a LPB-1 circuit or simmilar at the output to boost it, that's what im gunna do.
Seems an easy way to fix the problem, this one should work http://www.musikding.de/Kits/Musikding- ... ::616.html but once again it needs some work to find how to plug it properly :lol:
I think that the top middle lug of the switch is the output wire you'd want to splice it between, someone else tracing the switching for confirmation would be useful.

User avatar
Binuts
Information
Posts: 6
Joined: 05 Jul 2012, 09:51

Post by Binuts »

Scruffie wrote:I think that the top middle lug of the switch is the output wire you'd want to splice it between, someone else tracing the switching for confirmation would be useful.
But you'd need to link the LPB-1 to the 3PDT of the phaser right ? so is only activated when you switch the phaser on.

User avatar
Scruffie
Opamp Operator
Information
Posts: 1739
Joined: 13 Mar 2009, 17:59
Location: UK
Has thanked: 28 times
Been thanked: 170 times

Post by Scruffie »

Binuts wrote:
Scruffie wrote:I think that the top middle lug of the switch is the output wire you'd want to splice it between, someone else tracing the switching for confirmation would be useful.
But you'd need to link the LPB-1 to the 3PDT of the phaser right ? so is only activated when you switch the phaser on.
You want it between the phaser output and the 3PDT, so it's basically part of the circuit.

I can't remember if I had that in mind when I was trying to work out the switching... probably did.

Post Reply