comparison of 2 phasers

[human fly]

hi folks, newbie posting - also electronics newbie/novice, so you may
have to state the obvious  -

2 phaser pedals i'm looking at: Nobels PH-D and Arion SPH-1.
the Arion is the one i have. 1st difference is that it has stereo
output, against Nobel's mono.

Nobels PH-D:
http://www.experimentalistsanonymous.com/diy/Schematics/Phasers/Nobels%20PH-D.pdf

http://www.effectsdatabase.com/model/nobels/phd
Consumption    max. 15mA
Input impedance    1Mohm
Output impedance    2Kohm
Max. input    -6dBm

Arion SPH-1:
(schematic>)
http://postimg.org/image/c5r2a11lh/
http://www.effectsdatabase.com/model/arion/sph1

Consumption Current - DC 9V 17mA
Input Impedance - 100K ohms
Output Impedance - 10K ohms or more
Maximum Input Level - 0dB, 0dB = 1 V
Maximum Output Level - +6dB, 0dB = 1 V
Noise Level - -50dB, 0dB = 1 V input short
Phase Shift - 4 step (720 degrees)
LFO SPeed - 6sec - 100ms
Controls - Rate, Depth, Resonance
Other Functions - Pedal sw, check indicator, mode sw (OUT 2)
Jacks - Input jack, output jacks 1 and 2, AC adapter jack
(also says:
Input Impedance    300K ohm
Load Output Impedance    10K ohm
Maximum Input Level    0dB (0dB = 1V)
Noise Level    -69dB (0dB = 1V Input Short)
LFO Speed    16sec ~ 100ms
Phase    shift, 4 steps)

so, i'd like to make the Arion more interesting, with more range,
more options - ?? any ideas ?? i really don't know what i'm doing,
-but i pick up quickly - so some guidance  would be very useful. thanks!

[duck_arse]

before the helpful types come along, human, I just want to say great name, great song, and welcome to the forum. carry on.

[human fly]

nobels:


arion:

[human fly]

thanks...and may i compliment you on your moniker   

i think, if someone wants to give a run-through on what's going on
in these circuits, would be a great help. they seem pretty similar.
the Nobels has an extra couple of controls, and i'm thinking bandwidth
or similar must be achievable. remember: i don't know what i'm doing ! 

[Scruffie]

They're not the same, both 4 stage phasers yes but one's OTA based, the other FET.

If you want to mod the Arion have a look at mods for the phase 90, might give some ideas.

[Kipper4]

"also electronics newbie/novice, so you may
have to state the obvious "

First off welcome to the forum.



Not to try and put a damper on your ambition but
I would not advise you to start off with a complex build like this as a newbie/novice to electronics.
Start small and work your way up is my advice.
Choose something with less than a dozen componants

Build up your understanding of how it works, schematic's, layouts, soldering and desoldering skills, componant recognition, debugging, the list is long.
You will be less frustrated and enjoy the fruits of working pedals instead of a bag of junked unsalvagable boards.

You can feel free to go get what you want.

I've been doing this nigh on 4 years with no electrical schooling background and still have only a vague understanding of how some of the more complex builds work.

Thanks to the good people here I've come a long way.
But still have a ways to go.

Dive in build some stuff ,this is a very rewarding hobby.
And again welcome to the gang

Rich

[StephenGiles]

"also electronics newbie/novice, so you may
have to state the obvious "

First off welcome to the forum.



Not to try and put a damper on your ambition but
I would not advise you to start off with a complex build like this as a newbie/novice to electronics.
Start small and work your way up is my advice.
Choose something with less than a dozen componants

Build up your understanding of how it works, schematic's, layouts, soldering and desoldering skills, componant recognition, debugging, the list is long.
You will be less frustrated and enjoy the fruits of working pedals instead of a bag of junked unsalvagable boards.

You can feel free to go get what you want.

I've been doing this nigh on 4 years with no electrical schooling background and still have only a vague understanding of how some of the more complex builds work.

Thanks to the good people here I've come a long way.
But still have a ways to go.

Dive in build some stuff ,this is a very rewarding hobby.
And again welcome to the gang

Rich

Well, the first pedal build I did was the 4 stage Univox Microphaze in the 1970s -straight to veroboard. Now this was certainly no less difficult than the two phasers above - so build, make mistakes, find out why, put them right and get the bugger working!!!

[duck_arse]

h fly - yes, you may moniker me. once you've done that, it's reading time. get yourself over to geofex.com, read everything you can find. there is a page there on phasers and flangers, read that. then read all at AMZ. ALL! you will still want more, so also http://sound.westhost.com. there are other sites, but your head will be spinning by then, so come back and tell us where you're at.

or, jump in and vero it. them. both.

[Mark Hammer]

If I've understood the post correctly, the intent is to mod the Arion, not build the Arion or Nobels.  If I am wrong about that, note that the Nobels relies on CA3080s which will be expensive and difficult to get.

The simplest, and most straightforward mods for the Arion will be to provide a choice of making the phasing sound subtler by increasing the values of R36 and R32.  These mix the phase-shift signal with the clean signal.  They are currently set for 50/50 mix which yields the deepest notches.  Increasing their value by some amount (e.g., up to perhaps 44k, or 22k+22k) will allow the phase-shift effect to be moved a bit to the background when you want a taste but don't want it in your face.

VR3 is the on-board trimmer that sets the maximum resonance before oscillation sets in.  One of the things missing in that path is a capacitor to reduce the low end in the feedback path.  And THAT is the part that produces the howling that VR3 attempts to prevent.  You will be able to set VR3 for a more intense feedback level if you insert a suitable cap value to trim some of the bass off.  It's hard to read the value of the resistor after VR3, but I'll assume that, given the 100k value of VR3, that it is likely 22k.  Given that VR3 will probably be set to somewhere around half to 2/3 its maximum value, that gives us a combined resistance of around 80k, which would recommend a cap value of .01uf (10nf) as a starting value, since it will begin to roll off bass in the feedback path around 200hz.   But since rolling off bass will permit reducing the value of VR3 to get more feedback signal, then that might change our total resistance from 22k+about 60k to something less.  In which case you might want to move up to .012uf (12nf).  But .01 will be a serviceable value to start with.