Behringer PH9 - a cheap Phase 90 made for modding

Started by Mark Hammer, July 02, 2010, 02:52:13 PM

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CynicalMan

Even the word "true" seems to be used for anything a manufacturer wants to make seem good. True bypass, true analog (although 100% is often used here), true stereo, true hardwire, true tube, true vibrato, and so on. It's a buzzword that implies that their competitors are all FAKE!

Mark Hammer

Quote from: zombiwoof on July 05, 2010, 02:11:33 PM
Maxon is now using a mini pc-mount 4PDT switch in some of their pedals for true bypass, not exactly what you're asking for but close (it's the pic on the right down at the bottom of the page under "updates"):

http://www.stinkfoot.se/andreas/diy/articles/maxon.htm

It might be a proprietary part, though.

Al
It's kind of hard to tell from the picture, but it looks like they have simply used two DPDT switches and the actuator pushes them both down at once.  I suppose if you're Maxon, you can arrange to have some kind of custom plastic bracket made to fit over the top of two of the switches shown here, and present the same physical interface to the actuator that a single switch normally would.  I don't know if that's what they do, of course, but if they already have thousands of the switches bought, and it would cost big bucks to have a custom switch made, then simply fabricating a bracket is the cheaper option.  I have a bunch of those little switches.  I should see if I can rig up a 4PDT for myself.  That would sure be convenient for those folks who want to have simple non-electronic order switching via a simple push button.

zombiwoof

Quote from: Mark Hammer on July 05, 2010, 03:53:13 PM
Quote from: zombiwoof on July 05, 2010, 02:11:33 PM
Maxon is now using a mini pc-mount 4PDT switch in some of their pedals for true bypass, not exactly what you're asking for but close (it's the pic on the right down at the bottom of the page under "updates"):

http://www.stinkfoot.se/andreas/diy/articles/maxon.htm

It might be a proprietary part, though.

Al
It's kind of hard to tell from the picture, but it looks like they have simply used two DPDT switches and the actuator pushes them both down at once.  I suppose if you're Maxon, you can arrange to have some kind of custom plastic bracket made to fit over the top of two of the switches shown here, and present the same physical interface to the actuator that a single switch normally would.  I don't know if that's what they do, of course, but if they already have thousands of the switches bought, and it would cost big bucks to have a custom switch made, then simply fabricating a bracket is the cheaper option.  I have a bunch of those little switches.  I should see if I can rig up a 4PDT for myself.  That would sure be convenient for those folks who want to have simple non-electronic order switching via a simple push button.


I don't think it makes a difference, but the pic you posted there is actually the DPDT they used on the earlier pedals, the 4PDT switch is pictured down near the bottom of the page I linked to (they only show the bottom of it, it's the pic to the right).  You could be right, but it looks to me like the 4PDT switch is actually a different switch, not a modified version of the DPDT switch.  The board part of it is different (obviously, as it has more contacts).

Al

DougH

Sorry if I missed this already in the thread, but if the input impedance is high enough it doesn't really matter whether it's "half-assed bypass" or not. I did this to my wah where I added an input buffer and left the bypass arrangement alone. It sounds fine, and much better than before when switched to bypass.
"I can explain it to you, but I can't understand it for you."

Mark Hammer

Which is precisely why the output-only switching on this thing doesn't bother me in the least.

zombiwoof

Quote from: DougH on July 05, 2010, 05:01:22 PM
Sorry if I missed this already in the thread, but if the input impedance is high enough it doesn't really matter whether it's "half-assed bypass" or not. I did this to my wah where I added an input buffer and left the bypass arrangement alone. It sounds fine, and much better than before when switched to bypass.

Read this about the "half assed bypass" of MXR pedals, and why that isn't the only consideration:

http://www.stinkfoot.se/andreas/diy/articles/bypass3.htm    (the MXR part) 

The other Stinkfoot bypass articles are also good info.

Personally, in a wah, I prefer true bypass to using an input buffer (which is what Dunlop does on many of their current wahs), but that's up to you.  And true bypass is much easier IMO to implement.  The bypass in MXR pedals is notorious for being bad, though.  I don't know what the Behringer pedal is using, since it's using the actuator and we haven't heard what is being done in the rest of the circuit.

The main point of all this is that Behringer is claiming "true hardwire bypass" in these pedals, which generally is taken to be true bypass, but it seems they are not being truthful.

Al

Mark Hammer

During this morning's bus ride in to work, I was looking through a back issue of Guitar Player, and came across an ad for a Mod Tone Clean Boost pedal.  Now, I'm sure they make a fine product, but the ad copy on this one was not at all helpful: "Proprietary circuit design allows up to 25db of boost w/o adding gain".  Yep, and I've got a heaping bowlful of ice cream here for you with 40g of fat, and 50g of sugar, but it's "calorie-free".

I agree with Stinkfoot that the lack of standardization in terminology is exasperating.  There are some music store staff and customers knowledgeable enough to be able to rise above that, but the vast majority are not, making them susceptible to all sorts of misconceptions and resulting frustration.  I'm not the conspiratorial type, so I don't view it as intentional.  But jeez Louise, it would be helpful if everybody used the same words to talk abut the same things! :icon_rolleyes:

DougH

Quote from: zombiwoof on July 05, 2010, 10:57:08 PM
Quote from: DougH on July 05, 2010, 05:01:22 PM
Sorry if I missed this already in the thread, but if the input impedance is high enough it doesn't really matter whether it's "half-assed bypass" or not. I did this to my wah where I added an input buffer and left the bypass arrangement alone. It sounds fine, and much better than before when switched to bypass.

Read this about the "half assed bypass" of MXR pedals, and why that isn't the only consideration:

http://www.stinkfoot.se/andreas/diy/articles/bypass3.htm    (the MXR part)  



There's no reason an input buffer has to have a 470k Zin. With my JFET buffer I'm using a 1M gate resistor which sets Zin essentially to 1M. For higher Z use a 10M. 10M (even 1M with my stuff) is a negligible reduction in Zin for whatever is behind the pedal in question.
"I can explain it to you, but I can't understand it for you."

Mark Hammer

Okay, here are some points of interest, courtesy of the linked-to picture that Cynicalman posted.

The yellow circle in the upper left is the 1M resistor that sets the sweep width.  The hole just to its right is for adjustment of the trimpot, although the trimpot is glued in place.
At the bottom, you'll see a 2k2 resistor where the fuschia rectangle is.  That sets the brightness of the LED, and is what I replaced with 10k.
You'll also see a 6-pin configuration  inside the green rectangle, which are the pins of the little board-mount DPDT switch, used for bypass.

dan5150

Mark - Thanks for starting this thread and leading the investigation. :-)

I too assumed that these things really were "True Bypass" in the sense we all are used to. When I first engaged the switch and it didn't have the familiar "click", I became sceptical. I then opened it up, and the mechanical-plunger-hitting-microswitch thing really had me scratching my head.

I own both the PH9 and the DC9. I find the price/performance ratio to be just fine. Plus, I don't think they are as "noisy" as other Berhinger pedals (in the plastic cases) that I have. My biggest complaint about any Berhinger pedal is their ridiculously bright "Lazik inspired" LED's.

Now that Mark has pointed out the location of the resistor to change to help with that, my question is "how"? I have never attempted to work on a board with SMD components. I am also guessing your replacement resistor isn't SMD, correct?




defaced

Removing an SMD resistor is pretty easy if you don't want to keep it.  Just lay your soldering iron on it and it'll heat up enough and de-solder itself.  You can replaced it with a regular leaded resistor. You'll just have to lay the resistor flat and bend the leads to lay over the pads.  Youtube has some great SMD soldering videos, as does SparkFun electronics. 
http://www.sparkfun.com/commerce/advanced_search_result.php?keywords=smd&x=0&y=0&search_section=tutorials
-Mike

Mark Hammer

And since there is room for adding things, note that 1/8w resistors are the thing to use.  You can probably buy a variety pack of them at Radio Shack or similar.  Bend the leads at right angles to the resistor and solder it lying on its side.  The pads on the board are big enough, and the resistor leads are small enough, that you can retrofit a 1/8w component where an SMT component used to be in many cases.

zombiwoof

Quote from: Mark Hammer on July 06, 2010, 10:11:24 PM
Okay, here are some points of interest, courtesy of the linked-to picture that Cynicalman posted.

The yellow circle in the upper left is the 1M resistor that sets the sweep width.  The hole just to its right is for adjustment of the trimpot, although the trimpot is glued in place.
At the bottom, you'll see a 2k2 resistor where the fuschia rectangle is.  That sets the brightness of the LED, and is what I replaced with 10k.
You'll also see a 6-pin configuration  inside the green rectangle, which are the pins of the little board-mount DPDT switch, used for bypass.

Did you find it necessary to change the "sweep width" resistor you pointed out?.  I don't think you said.

Thanks,
Al

Mark Hammer

It's not "necessary, but it makes for a pleasing difference.  Generally, you don't want as much width for faster speeds, and more width for slower ones.  MXR selected a compromise value that worked acceptably for all speeds.  Giving yourself a little more, and a little less width than what the stock unit provides can yield sounds better suited to your sonic goals.

RG shows a 1M pot in the drawing on his site.  I did that, and measured the pot resistance at the point where the control seemed to do nothing useful.  I didn't find anything below the 700k mark to be particularly useful, so I used a 680k fixed resistor in series with 500k to give a bit less, and a bit more width.  Restricting the current going to the FET gates allows the LFO to push them more, so greater values then 1M = more width, and values less than 1M = less width.

ledvedder

Does anyone have any updates on this?  I just got one, and it doesn't seem to have much "phase" effect unless the knob is totally clockwise, making that fast, warbly effect.  I like to use a slow, sweeping phase like Van Halen's Eruption.  If I turn the rate knob counter-clockwise for a slower sweep, the phase effect seems to almost disappear.  I've tried adjusting the internal trimpot, but I've had no luck.

Mark Hammer

#35
Well that doesn't sound right.  If it's new, I'd suggest returning it for another.

newfish

Quote from: Mark Hammer on November 08, 2010, 09:18:55 AM
Well that doesn't sound right.  If it'new, I'd suggest returning it for another.

+1

I bought one of these the other week (for the amount of 'Phasing' I use, the Behringer is more than adequate).

My pedal still has a well-defined 'sweep' to it even at slower speeds.

Happiness is a warm etchant bath.

modelmonster

 :)
Hello I am so glad to have found this thread!
I want to add a SWTC stupidly wonderful tone control and volume control to this pedal

I got this pedal years ago in a trade and it did not seem to work at all.
so i used the case for something else.
fast forward 3 or 4 years i found this pedal in my junk drawer and noticed the internal trim pot .
I plugged it in and started messing with  the trim pot and it doesnt really do a phase sound..
but what it does is act as a very cool boost with  my big muff. very cool..
however it is a bit bright and has  to big of a volume boost.

so any way to add Mark Hammer stupidly wonderful tone control or other and volume control to this?

any help would be greatly appreciated
i am a beginner btw
thanks


anotherjim

I've screened the B enclosures with rattle can conductive graphite paint. If you want to dull the LED you can do what I did and forget to mask off the clear plastic lens over the LED.

Mark Hammer

Quote from: modelmonster on November 26, 2021, 11:05:52 PM
:)
Hello I am so glad to have found this thread!
I want to add a SWTC stupidly wonderful tone control and volume control to this pedal

I got this pedal years ago in a trade and it did not seem to work at all.
so i used the case for something else.
fast forward 3 or 4 years i found this pedal in my junk drawer and noticed the internal trim pot .
I plugged it in and started messing with  the trim pot and it doesnt really do a phase sound..
but what it does is act as a very cool boost with  my big muff. very cool..
however it is a bit bright and has  to big of a volume boost.

so any way to add Mark Hammer stupidly wonderful tone control or other and volume control to this?

any help would be greatly appreciated
i am a beginner btw
thanks
Wait, are we talking about the same pedal?  The trimpot should not be altering the level.  And even if it does, for whatever reason, there is not enough increment to volume to require a volume control.

As for a SWTC, it is a subtle control, that really only has an apparent effect when one has a significant boost to treble, such as on overdrive or distortion effects.  A phaser will not likely benefit from a SWTC.

Sorry to put a damper on your enthusiasm.  Stay enthusiastic.