Chorus clipping HELP!

[G.Bisson]

Recently I've been trying to troubleshoot a problem I've been having with two of my chorus pedals clipping, but I've no luck so I turn to you guys for some help.

There is clearly some clipping occuring when I turn on my chorus effects. Whenever unwanted noise is present in my signal I go through my usual checks to trace the source of the noise; try different patch cables, try different power supplies, play through different amps, play through DI direct into headphones, play through effect with a passive bass, play through the effect with a active bass. When that didn't work I removed the pedal from my chain and tried the effect in amp's effects loop, then tried it directly into amp's input. Then tried putting a buffer and gain booster before the chorus pedal to see if it would distort more or less. Absolutely no change in the clipping behavior. Dialing back the 'blend' control on the chorus pedal pushed the clipping further back in the mix, which clearly tells me that it is the chorus effect itself that is distorting. Notes below C (on either the E or A string) caused significantly more clipping and was the only thing that changed the clipping response.

The two chorus pedals this is happening with are both Maxons: CS9Pro & CS550. Just to check, I also played through a Visual Sound H2O chorus and didn't experience any clipping at all. Are these two Maxons not bass friendly chorus pedals? I've seen a few other folks with CS9's on their boards so I'm thinking it must be bass friendly.
I've never understood why some manufacturers make bass specific chorus pedals. Someone please enlighten me on this. Are some chorus pedals incompatible with the low frequency range of bass guitars?
Checking the specifications for the CS550 the manual says "maximum output level: +5dB". Compared to the PH350 phaser I also have and never experienced any clipping, it list "maximum output level: +8dB". This leads me to believe there isn't enough headroom to accommodate bass guitar. Can't find similar info from the other chorus pedals to compare with.

I bought the CS550 brand new a year ago and never noticed the problem until recently I bought a CS9Pro used. The CS9 clips prominently, which prompted my comparison with other choruses. Now that I notice my CS550 clipping it is killing me, as I love it's tone and would hate to replace it with anything else . PLEASE HELP!

[G.Bisson]

any thoughts?

[bongomania]

I don't have any solid suggestions/knowledge on this, but here are a couple thoughts:

Headroom isn't related to output level, so the +5/+8 discrepancy isn't the problem.

With "bass-specific" chorus pedals, the difference is sometimes just the amount of low end that passes through the circuit altogether; and sometimes it's the amount of low end that is introduced to the delayed side of the chorus (chorus being a mix of delayed and un-delayed signal). Some designers/users think more bass should be included in the delay line, for heavier low end; others think less should be included, for tighter, more articulate low end.

I may be mistaken, but I think the H20 is digital, while the Maxons are analog.

[AndyLES]

The H20 is analog actually, but the literature states that it can handle the low frequencies of bass and even keyboards.

I personally have never liked the Maxon stuff for guitar OR bass...for the money, I think the workmanship overall is shoddy. I had some of their pedals, and I always had problems - volume drops, faulty switches, weird noises, etc.

[Eric!]

The Liquid Chorus by itself is pretty awesome...

Are there bias trimpots in the Maxons?

[G.Bisson]

The H2O chorus is analog. The delay channel is an analog/digital hybrid and it will clip with a strong signal but the chorus channel has never clipped.

I've never opened up any of my Maxon's before. I'll take look into them to see if there are any goodies to tweak inside.

[G.Bisson]

Opened up the CS9 last night.
Found two internal pots inside. One labeled 'RT1' on the board and stamped '103' on top, the other labeled 'RT2' and stamped '203'.
RT1 was set a little past 1o'clock, RT2 was set at noon.
Turning RT1 I found it was shifting the mid tone sweet spot and intensity of the chorus. Turned near max in either direction the chorus was almost absent although some modulation sweeping could still be heard far back in the mix. This also mixed out most of the clipping I'm hearing. Turned a little past factory setting generated more feedback and lots more clipping. I couldn't find any setting that reduced clipping, although with RT1 dimed the clipping was being mixed out, but so was the chorus effect, so that isn't any solution to my problem. I set RT1 back to factory position where the chorus sounded best.
I couldn't determine what RT2 did. Turning past noon in either direction didn't change the chorus response. Thinking this pot may work in tandeem with another control on the faceplate, but I didn't experiement enough to find out. All I can hear from turning RT2 is what sounds like a change in impedence of some other load being mixed in. Set this back to factory position at 12o'clock and closed up the pedal. Those internal pots weren't going to solve my problem.

I then took my screwdrivers to my CS550 but didn't get far. The outer screws are star shaped with an inner nipple. I have a star driver that fits but couldn't use it with the nipple blocking the hole. Maxon really didn't want anyone taking a look at their high-end circuits, unless of course they are equipped with highly specialized electronics tools . A quick google search reveals my local Lowes sells a Torx security driver bit set for less than $10.
To Be Continued...