The MXR CSP-026 '74 Vintage Phase 90 is a hand-wired reissue of the original 1974 script-logo Phase 90, the very first version of the pedal, produced from 1974 to 1977. It is a phaser pedal built as a copy of the 1974 circuit, using six single op-amps, and it is finished in a similar dull orange shade to a vintage pedal, printed with the MXR script logo12.
Where it came from
MXR's approach to the reissue was to reverse engineer an original pedal that had been purchased in 1974 by Bob Cedro, a Dunlop engineer. The result is a hand-wired circuit board with original specification 1974 components, including select resistors paired with hand-matched FETs that aim to exactly recreate the original sound2. MusicRadar's history of the Phase 90 notes that the pedal replicates the original script-logo spec of 2N5952 JFET transistors and six 741 op-amps3.
"The pedal is finished in a similar dull orange shade as a vintage pedal, printed with the MXR script logo"
Controls and power
There is one control: a single Speed knob that comes with a removable rubber cap for easier adjustment by foot. The bypass switch is a Carling, and the input and output jacks are high quality Switchcraft parts2.
Power is where the vintage approach shows most. The pedal runs on a 9V battery, with no AC connector and no LED1. The battery is accessed by removing four screws and taking the pedal's base off2.
The CSP-026 cannot be run from a standard power supply: it has no AC connector and takes a 9V battery only1. MusicRadar's reviewer also noted it is not true bypass1.
How it sounds
MusicRadar's reviewer described the pedal's phasing as organic, "from the slowly shifting tonality at one extreme to the fast bubbling at the other", adding that "it's the silky quality of the phasing that is the real deal here"2.
In an A/B test against his own original vintage 1974 model, the reviewer found the sound was not identical, with a slightly different tonality, but neither pedal sounded better than the other, and MXR achieved its aim. His verdict: "If you want that mid-seventies Phase 90 sound this reissue is as close as you'll get to it without trawling Ebay"2.
His summary of the trade-offs:
How it compares
The CSP-026 sits among several Phase 90 variants MXR makes. It is a reissue of the earliest script-logo version, while the current MXR Phase 90 is the standard modern production model, and the MXR '74 Phase 90 and MXR Script Phase 90 offer other takes on the vintage voicing. For a wider look at the effect type, see the Phaser Pedals page2.
Videos
ProGuitarShopDemos
Sweetwater
jimdunlopusa
Questions
Does the MXR CSP-026 '74 Vintage Phase 90 have an LED?
No. The CSP-026 has no status LED, and no modern tweaks were added to the circuit. MusicRadar's review notes that the pedal was deliberately kept in as close to the original 1974 form as possible, which means no LED to show when the effect is on. Players used to a modern pedal's indicator light will need to go by ear.
Can the CSP-026 run on a power supply?
No. The CSP-026 has no AC connector and runs on a 9V battery only. Battery access is under the base, which is held by four screws. If your pedalboard is powered from a supply, this pedal is not designed for it, which is worth knowing before you plan a board around it.
How do you change the battery in the CSP-026?
You remove four screws and take the pedal's base off to reach the PP3 battery. There is no external battery door or AC jack, so battery changes are a hands-on job. MusicRadar's reviewer listed battery access among the pedal's drawbacks.
What transistors and op-amps does the CSP-026 use?
The CSP-026 replicates the original script-logo specification of 2N5952 JFET transistors and six 741 op-amps, according to MusicRadar's history of the Phase 90. The review adds that select resistors are paired with hand-matched FETs to recreate the original sound, on a hand-wired circuit board.
What is the difference between the CSP-026 and a standard Phase 90?
The CSP-026 is a hand-wired reissue of the very first Phase 90, the script-logo version made from 1974 to 1977, built with original-specification 1974 components including 2N5952 JFETs and six 741 op-amps. It has no LED and runs on battery only. A standard Phase 90 is a current-production pedal with modern conveniences and a block-logo look.
Does the CSP-026 sound like an original 1974 Phase 90?
Very close, though not identical. MusicRadar's reviewer A/B tested the CSP-026 against his own original 1974 model and found the sound was not identical, with a slightly different tonality, but neither pedal sounded better than the other. His verdict was that if you want the mid-seventies Phase 90 sound, this reissue is as close as you will get without buying an original.
Sources (3)
- MXR Phase 90 Analysis, GuitarPCB
- MXR CSP-026 '74 Vintage Phase 90 review, MusicRadar, 2008-05-23
- Meet your maker: MXR at 40, MusicRadar, 2014-12-04
