CE-5

Boss CE-5 Chorus Ensemble Pedal. The CE-5 began as a continuation of the same chorus circuit as the Boss CE-2 and CE-3. The General Information section elaborates on how the CE-5 unfolded.

Thermionic Studios owns a CE-5 that is the older, discontinued, analog version. The Boss CE-5 Chorus Ensemble continues to be made, but is only available now as the "new" (post 2001) digital version. Opinions of the digital (post-2001) version of CE-5 tend not to be positive.

Thermionic Studios has one(1) modified CE-5 available for rental.

Controls

Image from Amazon

The rightmost knob for "filter" on the CE-5 is a nested two-control tone knob.

• Knob 1 - "E. Level": (Effect Level) This knob increases the amount of effect (wet) signal. Dry signal always comes through at 100%.
• Knob 2 - "Rate": This knob sets the speed of the modulation of the chorus; clockwise increases the speed.
• Knob 3 - "Depth": This knob sets the depth of the sweep of the chorus; clockwise increases the depth of the sweep.
• Knob 4 - "Filter": This is a dual-knob with an inner- and outer- knob, controlling two separate tone controls.
  • Inner Knob - "High": sets the volume of the treble tones, clockwise is more treble.
  • Outer Knob - "Low": sets the volume of the bass tones, clockwise is more bass.
• Footswitch - "On/Off": Switch toggles the pedal on and off
• Output 1 - "Output A: This is the "mono" or wet+dry signal when Output B isn't being used. When Output B is used, Output A is pure wet signal.
• Output 2 - "Output B: This is the "stereo" or "dry only" output jack.

Free Vibrato!

In a pinch it is possible to change the CE-5 from a Chorus pedal to a straight Vibrato pedal by connecting the cord that you're sending to the amplifier into Output A and take a small patch cord and plug it into Output B an then into nothing else. This forces all the wet signal through Output A and the dry signal into Output B. The wet signal is vibrato. When combined (summed) with a non-modulated dry signal, the result is heard by the human ear as a chorus sound. If using this trick be aware that without the effect level at Max, the wet signal will not have unity with the dry signal, causing a volume loss when engaged.

Bypass:Buffered

Like all Boss pedals, the CE-5 has a buffered bypass.

General Information

"CE" Product Line

One of the effects that Boss started their line of pedals with was the CE-1 Chorus Ensemble. This is the old 1970s grey "bean" shaped pedal with two button switches on it. This effect still gets rave reviews on both the lushness and subtlety of the chorus effect. Boss then continued the "CE" designation when they converted to the "classic" 1U stompbox format that we're familiar with today. Their first was the "CE-2 Chorus" which implemented the same circuit, but in a simpler 2-control mono-based effect. Boss then released the "CE-3 Chorus" with the distinctive black knobs with red line indicators (like the Boss VB-2), and stereo outputs. Boss then changed direction and chorus designation and released the "CH-1 Super Chorus".

"CE" then reappeared with the "CE-5 Chorus Ensemble". The earlier CE-5 models share the same pedigree (and MN3007 bucket-brigade delay chip) as the CE-2 and CE-3 and are valued for such. Later models of the CE-5 discard the older analog design and use a new digital architecture. Panasonic stopped producing the MN3007 chip, causing Boss to change to the new digital architecture.

Identification

Since the analog and digital versions of this pedal are not immediately distinguishable, it can be difficult to find the analog version for sale online. If you're trying to determine the version of CE-5 you have (or are trying to buy online), there are some "easy" methods.

Most digital pedals can be quickly distinguished:

• First look at the color of the pedal. If the pedal is white, it's newer and will be digital.
• If the color is light blue:
  1. Check the label on the bottom of the pedal. If it's dark grey, it's the digital version.
  2. Check the PCB. The newer, digital version will also have "CE-5A" printed on it.

However, the analog CE-5s require a bit more checking:

• A light-blue pedal
• A non-grey back-side sticker
• A serial number with a second letter/first number combination that is earlier than "P1"[1]
• A PCB that has "CE-5" printed on it

If you're interested in buying a CE-5 online, you might need to convince the seller to take a picture of the bottom to get the serial number. If they'll open the pedal up and take a shot of the PCB, even better.

There is a silver lining to all this trouble. This is because when you find a seller of an analog CE-5, he or she will likely be unaware of any difference. It's usually possible to get a seller of an analog CE-5 to sell at a price that's the same as used digital CE-5s. Analog CE-5s can still be had rather inexpensively. Sometimes, they just take a little time and some effort to find.

Modifications

It is also possible to modify the older, analog version of the CE-5 for greater function:

From DIYStompboxes.com:

"Change C22 from 5pF to 22pF (or just solder a 22 pF across C22 on the back of the board). Increasing C22 increases the amount of delay through the bucket-brigade IC (analog delay). Increasing C22 to 22pF has a dramatic and wonderful effect on the depth of the chorus effect."

Pedal Manual

• Boss CE-5 Chorus Ensemble Owner's Manual

Phase Inversion: No

Our review of the schematic suggests to us that the Boss CE-5 does NOT invert the signal phase. Our explanation is going to be a bit more complicated than that for other pedals...

Output B

We're listing Output B first as it's the easiest to trace (and therefore learn something from).

Schematic ID	Electronic Part	Action	Phase State
Q1	2SK184	Does not Invert	Original
Q2	2SC3378	Does not Invert	Original

For the transistors driving a signal to Output B, we don't read any appearance of inverting electronics, so Output B remains In-Phase.

Output A

Output A is going to be a good bit harder to trace:

Schematic ID	Electronic Part	Action	Phase State
Q1	2SK184	Does not Invert	Original
IC1b	M5218	Inverts	Inverted
Q6	2SC3378	Does not Invert	Inverted
Q5	2SC3378	Does not Invert	Inverted
IC2b	M5218	Does not Invert	Inverted
IC3a	M5218	Inverts	Reverted
IC2a	M5218	Inverts	Inverted
IC2b	M5218	Inverts	Reverted
IC3b	M5218	Does not Invert	Reverted
Q3	2SK118	Inverts	Inverted
IC1a	M5218	Inverts	Reverted (phase back to Original)

Well, this at least appears to be good. If phase between Output B and Output A were different, that would be a problem! We think this has something to do with the fact that the signal goes through IC2b twice. At least the way we read it, the signal goes through IC2b first, without inverting, for the low frequency filter, and then goes back through IC2b and gets inverted and then goes on its way to the high frequency filter. Of course, we're not as experienced with solid-state electronics, so this is some informed guesswork on our part; but it also helps us get to where Output A exits the pedal In-Phase...

This is interesting

Notice that there is also signal that gets dumped to the ground of Output B:

Schematic ID	Electronic Part	Action	Phase State
Q3	2SK118	Inverts	Inverted
Q4	2SC2458	Does not Invert	Inverted

Schematic

© Copyright 1991, Roland Corporation.

The schematic was sourced from the Service Manual linked below. The service manual is being made available since the schematic may not be legible enough for everyone interested in viewing it.

• Boss CE-5 Service Manual

Artists

• Melissa Auf der Maur
• Jerry Cantrell
• Marty Friedman
• Gus G.
• Jeff Healey
• George Lynch
• Yngwie Malmsteen
• Steve Vai
• Eddie Van Halen
• Zakk Wylde

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Additional Sources

1. http://www.bossarea.com/boss-ce-5-chorus-ensemble/
2. http://equipboard.com/items/boss-ce-5-chorus-ensemble?src=pim_name