The JAM Dyna-ssoR is an analog compressor and sustainer pedal from JAM Pedals, the Greek effects maker. It is built around a rare NOS CA3080 chip, a vintage part JAM Pedals credits with "the vintage attack, compression and sustain associated with classic compressor designs"1. The company describes it as combining the spirit of the classic Ross and MXR Dyna Comp circuits in a simple two-knob design2.
JAM Pedals' own description of what the pedal does: "The Dyna-ssoR is a musical NOS CA3080 compressor that delivers vintage punch, satisfying squash and long sustain without flattening the life out of your tone"1. The circuit is tuned to control dynamics while keeping the instrument's original character and musical expression intact3.
The controls: Sustain and Level
The Dyna-ssoR keeps things to two front-panel knobs4:
| Control | What it does |
|---|---|
| Sustain | Sets compression and sustain. Turn it up for thumpy, compressed attack and singing hold, or back it down to gently control peaks while keeping playing dynamics intact1 |
| Level | Sets output, so you can match your volume or push the next stage6 |
Delicious Audio's reviewer explained the Sustain knob in practical terms: the more you turn it clockwise, the more the signal gets compressed, which makes loud sounds quieter and quiet sounds louder, squashing the sound and lengthening sustained notes4. That is the classic two-knob compressor layout inherited from the Ross and Dyna Comp designs the pedal draws on.
Circuit lineage: Ross and Dyna Comp
JAM Pedals says the Dyna-ssoR "combines the spirit of classic Ross and Dyna Comp circuits in a simple two-knob design"2. The Delicious Audio review puts it the same way, describing the pedal as designed to combine the best of the MXR DynaComp and Ross Compressor, both considered legendary in the stomp box world4.
The key component is the CA3080, an operational transconductance amplifier that has been out of production for years, which is why JAM Pedals builds from NOS (new old stock) chips. The company says the rare chip delivers the vintage attack, compression and sustain associated with classic compressor designs1.
How it compares to an MXR Dyna Comp
The MXR Dyna Comp is the obvious reference point, and That Pedal Show compared the two directly in a short Effector Du Jour video in February 2024, pitting the Dyna-ssoR against Dan's 1970s script-logo MXR Dyna Comp7.
Dan's findings from that comparison:
The comparison runs 3:598. The broader record on the MXR side: TONEHOME notes the Dyna Comp is not considered tone-neutral, adding a specific coloring to the sound that many users appreciate, and that it also boosts the signal9. Ovnilab's review of the MXR Dynacomp adds that "the main difference is that the MXR has lower quality of components and construction" compared with the Ross and its clones10.
What reviewers said
Delicious Audio's Gus Green reviewed the Dyna-ssoR in November 2019 and was positive across the board4:
- He found the pedal designed so that tone remains intact no matter how much compression is applied4.
- In his experience, high Sustain settings did not ruin the tone the way other pedals he had used suffered when pushed that far4.
- His overall take was that a little goes a long way: subtle Sustain settings improved the tone immensely, adding life and detail4.
- He also tried it on bass and found it equally impressive there4.
"The Dyna-ssoR is designed in such a way that your tone seems to always remain intact no matter how much you compress it."
Artwork versions
JAM Pedals sells the Dyna-ssoR in several custom artwork editions, including the "Achenbach", "Relic" and "Lunar Trails" versions. The company's line on all of them: "Same sound, different artwork"11. Every limited artwork pedal is a one-of-a-kind hand-painted piece, so the pedal you receive will differ in detail from the photos shown11.
The Achenbach artwork version is listed as sold out on JAM Pedals' site as of October 202611. The other artwork versions share the same circuit and sound.
Players
JAM Pedals lists the Dyna-ssoR among its compressor offerings, tagging it as a compressor on its product page2124. The pedal is currently listed as sold out12.
Videos
JAM pedals
JAM pedals
JetCityMusic
Questions
What circuits is the JAM Dyna-ssoR based on?
JAM Pedals says the Dyna-ssoR combines the spirit of the classic Ross and MXR Dyna Comp circuits in a simple two-knob design. The Delicious Audio review likewise describes it as designed to combine the best of the MXR DynaComp and Ross Compressor, both long-standing references in the compressor world.
Is there a bass version of the JAM Dyna-ssoR?
Yes. Delicious Audio's reviewer reported in 2019 that JAM Pedals makes a Bass version of the Dyna-ssoR that can be purchased. The same reviewer also tried the standard pedal on bass and found it equally impressive there.
Is the JAM Dyna-ssoR analog?
Yes. JAM Pedals describes its pedals, the Dyna-ssoR included, as analog designs, and the Dyna-ssoR is built around a rare NOS CA3080 chip, a vintage operational transconductance amplifier no longer in production.
Do the artwork versions of the Dyna-ssoR sound different?
No. JAM Pedals states plainly that the custom artwork versions, such as the Achenbach, Relic and Lunar Trails editions, offer the same sound with different artwork. Each limited artwork pedal is a one-of-a-kind hand-painted piece, so the paintwork differs in detail from the photos.
How does the JAM Dyna-ssoR compare to an MXR Dyna Comp?
On That Pedal Show, Dan found the JAM a bit more even than his 1970s MXR Dyna Comp, and noted the old Dyna Comp has less mids. The MXR is also not considered tone-neutral, adding its own coloring, while JAM tunes the Dyna-ssoR to preserve the instrument's original character.
What does the Sustain knob do on the Dyna-ssoR?
Sustain sets the amount of compression and sustain. Turning it clockwise compresses the signal more, making loud sounds quieter and quiet sounds louder, squashing the sound and lengthening sustained notes. Backed off, it gently controls peaks while keeping playing dynamics intact.
Sources (12)
- “Achenbach” Dyna-ssoR, JAM Pedals (jampedals.com)
- Dyna-ssoR, JAM Pedals (www.jampedals.com)
- Dyna-ssoR B-Stock, JAM Pedals (www.jampedals.com)
- Guitar Pedal Reviews: JAM Dyna-ssoR Compressor/Sustainer, Delicious Audio, 2019-11-12
- “Relic” Pink Flow, JAM Pedals (jampedals.com)
- “Relic” Dyna-ssoR, JAM Pedals (jampedals.com)
- JAM Pedals Dynassor & ’70s MXR Dyna Comp Effector Du Jour, That Pedal Show (YouTube), 2024-02-27
- JAM Pedals Dynassor & ’70s MXR Dyna Comp Effector Du Jour, That Pedal Show, 2024-02-27
- TONEHOME, TONEHOME
- MXR Dynacomp, ovnilab.com, 2006
- “Lunar Trails” Dyna-ssoR, JAM Pedals (jampedals.com)
- Dweezil Zappa, JAM Pedals (www.jampedals.com)
Dweezil Zappa
