Any mods I can do to a Boss PH-1r?

[Karmasound]

Like speed, improving tone ect...

Thanks

[jimbob]

If you ever want to make a few dollars back on it- you wont touch it. I have the ph-2 and really like it the way it is. To mod an older Boss pedal like that will surely make it less valuable.

[stm]

Is there an schematic or simple diagram for the Boss PH-1 and PH-2?

I wonder if they are 2 or 4 or other number of stages phasers !

[MartyMart]

I echo what jimbob said, I have one and was recently offered 200 bucks for it !!!
They are very rare and are going up in price, hang on or sell and buy/build something else !!

Marty.

[Karmasound]

Well the thing is is that I bought it a few years ago. I have recently become intersted in electronics so I opened it up and it looks like someone has already hacked into it.

Some of the circuit traces must have been ripped and was soldered back with copper wire.


I wish I would have known that when I bought it but the seller didn't know or didn't tell me.

Other than that it sounds good and works well.

[Karmasound]

Before I had looked inside of it I was trying to sell it for $60 for months and nobody was interested.

There are some on ebay for that price all the time.

I don't want to sell it know since it has been tampered with.

[Ry]

I'm in the same boat, I bought one for $15 about 10 years ago, but it has been tampered with.  It distorts in a really unpleasant way at high resonance settings.  I've been meaning to fix it, but I haven't been able to find a schematic.

Those of you that have one...is this normal?  Maybe it hasn't been messed with.  If so, I would love to get $200 for it!!

Ry

[oversight_failure]

I just bought one of these a few weeks ago for $20.  It works fine, except for the fact the depth pot is completely gone and the wires were wrapped up in tape.  Can one of you guys give me the value for that pot?  I'm guessing 100k, but I'd like to be sure.

[jimbob]

oversight-sounds like a great deal assuming thats the only problem. Goodluck.

[MartyMart]

I'm in the same boat, I bought one for $15 about 10 years ago, but it has been tampered with.  It distorts in a really unpleasant way at high resonance settings.  I've been meaning to fix it, but I haven't been able to find a schematic.

Those of you that have one...is this normal?  Maybe it hasn't been messed with.  If so, I would love to get $200 for it!!

Ry

WOW  now thats CHEAP !!!!
You guys should sell on Ebay and offer the goods to Europe, they are as rare as Hens Teeth over here !!
You will get near the 200 bucks mark for a good PH1r, I have to add that mine is "boxed" and totally "mint"  looks like new  

Marty

[RickL]

Depth pot is marked 10kB on mine.

[R.Kent S.]

Is there an schematic or simple diagram for the Boss PH-1 and PH-2?

I wonder if they are 2 or 4 or other number of stages phasers !

The Ph-1 and PH-1r are four stage phasers, I have an original PH-1 (no resonance control),the depth control is 100kB, the rate is 1MC, both Alps pots of course. I'm looking for a schematic also, but haven't run across one as I'd love to convert my PH-1 to a PH-1r ...That being said, I wouldn't muck with a Ph-1r, as they are really nice little units as is.
Any mod that can be done to any four stage phaser can be done to these.

[Ry]

Can anyone tell me if they have distortion in their PH-1r's?  I really would like to fix mine.

Thanks,

Ry

[R.Kent S.]

Can anyone tell me if they have distortion in their PH-1r's?  I really would like to fix mine.

Thanks,

Ry

When I did play thru a PH-1r (didn't own it though) I didn't notice any with increased resonance ... not much help, but I don't think with nominal signal levels that that should be a problem ... maybe one of the others can verify the actual feedback loop limiting resistor and trimpot setting values. Man, a schematic would be nice though ... :::crosses fingers::::
Oh, yeah the rate thing, the rate of sweep is controlled from the 1MC pot, wired as a variable resistor ...lower resistance=faster sweep;higher resistance equals slower sweep ... the Ph-1and 1r were 100mS ~ 16S ...although my 1MC pot actually measures 771k ...so just glancing at the circuit tells me that it may not be getting it's full slow 16S of sweep (too slow for me, so no big deal). I'd love to be able to make the thing do that step rise and fall that the PH-3 does, similar to a sample and hold type of thing. Best bet on fixing the overload problem is to have one of the pH-1r owners check the values of their FB loop components, and they check them against yours.

[Vsat]

Hmmm.... do the PH-1 or PH-2 have a an "IR3109" chip (or chips) inside?

The IR3109 is a filter chip that contains four OTA's wth built-in PMOS buffers. It is a custom chip that Roland used in a number of instruments/fx.

The half-rack Boss RPH-10 phaser used two of these for eight variable allpass stages.
Regards, Mike

[Ry]

mmm.... do the PH-1 or PH-2 have a an "IR3109" chip (or chips) inside?

The Ph-1r has 3 4558 ics and one tl022.  I opened mine up and found that it actually hasn't been tampered with.  Strange.

Ry

[R.Kent S.]

Hmmm.... do the PH-1 or PH-2 have a an "IR3109" chip (or chips) inside?

The IR3109 is a filter chip that contains four OTA's wth built-in PMOS buffers. It is a custom chip that Roland used in a number of instruments/fx.

The half-rack Boss RPH-10 phaser used two of these for eight variable allpass stages.
Regards, Mike

The PH-1 has two 14pin DIPs ... RCA3403 (IIRC), that are quad opamps, plain and simple ... I *assume* that the PH-1r has the same ... although the PH-1r may have a different circuit for improved SNR, better headroom, etc. Everything else *appears* to be standard BOSS as to the SRflip-flop,I/O buffers and switching fets.
So no, the PH-1 has two quad opamps for the phase shift stages

[Vsat]

Interesting... so the PH-1 & PH-1R is probably a fairly typical unit usig FET's as variable resistors (unless LDR's are being used). The 3403 is indeed a quad op amp that works well on single supply - sort of an LM324 with better output stage for audio (but still a very old chip). BTW I've been told that the PH-2 has a very "plastic-like, almost digital tone"...perhaps it uses the IR3109.
Regards, Mike

[Ry]

The ph-1r does indeed have FETs rather than optos.

I'm going to have to trace out the resonance circuit and see what could be contributing to the distortion in mine.

I have played a PH-2 quite a bit and I have to agree that it is very strange sounding, not really that pleasant.

[stm]

It would be interesting to know the FET type involved!