412 MRBW M75-GNR


Released on November 29, 2019.

The “412 MRBW” is based on and seeking to recreate the sound of a 1971 Marshall® 1960B 4x12 closed back cabinet with “basketweave” salt-and-pepper grill cloth.

The “M75-GNR” is based on and seeking to recreate the sound of 12 inch, 16-ohm, 75-Hz Pulsonic cone Celestion® T1221 G12M-25 speakers made in March of 1971 with a “Greatly Neutral Response” for M25’s

The Cabinet (412 MRBW)
"The salt-n-pepper (which time has faded most of the ink to a resting brown) model 1960 "basketweave" cabinets retain several small design alterations from the later issued (and more heavily copied in the future) "checkerboard" clothed iterations which makes them distinctly unique. So far as the cabinet design goes, this lends itself to a slightly more resonant and mid frequency pushed tonality. The thick grill covering, however, is where most of the sonic signature is created that makes these cabinets have a sound of their own, and a coveted one at that. This thick cloth significantly dampens the high end, leaving what comes through to have a very low mid centric tone by comparison. This very much suited and offset the speakers of this time, which contrary to popular belief (because of this grill covering), were actually very bright by today's standards for British speakers, depending on how much past the point of operational limits abuse the speaker has taken over its lifespan. This specific 1960B specimen has a very special mojo it imparts to this augmented lower midrange, and while it is certainly warm in character, it is not profusely muted in its overall sound, and has a very organic cohesion to the various elements of the frequency spectrum." The Speaker (M75-GNR)
"The pre-Rola G12M is one of the foremost staples of and centerpieces to the sound of rock 'n' roll. Commonly referred to as "greenbacks" due to the plastic magnet covering, these speakers have a very elite position in music equipment history. Conditions and tonality of these old speakers can vary quite a bit, but they often follow the pattern of their original design. When removed from their thick grilled cabinets and placed on their own, these older Pulsonic cone speakers actually have a very prominent top end compared to modern speakers, and the high resonance is shifted up a few thousand hertz. This particular speaker, however, in one specific area of the cone, has qualities to it that I have never heard in this make and model. This section of this one speaker has an incredibly even and full sound, filling in a lot of the cracks typically found in these kinds of drivers, resulting in its product ID nickname: the M75 with a Greatly Neutral Response." The Combination
"This exact cabinet and speaker combination (as well as the other companion speakers used in this specific grouping) were used for the rhythm guitars on the most expensive album ever produced, "Chinese Democracy" by the band Guns N' Roses. This specific enclosure was selected from an entire trailer full of speaker cabinets auditioned from other studios and rental facilities, and due to the nature of how many years that record took to make, was purchased outright by the band and made into a permanent fixture for those sessions until completion. After the fact, the cabinet was sold by a band member to later make its way into the OwnHammer inventory, and has since been recognized as the most iconic, universally enjoyed and celebrated, and diversely utilized single configuration impulse response library set of all time, and justifiably so."
- Kevin Rowe (OwnHammer Owner/Developer)

  • 16 carefully and strategically placed single mic files
  • 7 industry standard microphones:
    57 - 87 - 121 - 160 - 414 - 421 - 84 (aux)
  • 61 meticulously crafted proprietary multi-mic mixes
  • 8 voicing variations per mic and mix file
  • major production/mastering grade signal chain

Please read this section carefully!

Wave Audio (.wav)

Wave audio format IR's (.wav) are compatible with convolution reverb type loaders in recording software and outboard hardware units and are provided in:
  • 24 bit resolution
  • 44.1, 48, 88.2, and 96 kHz sample rates
  • minimum phase transformed
  • 208 millisecond Mono
  • 500 millisecond TrueStereo™


If your platform cannot load .wav files, make sure you explore the free or commercial conversion applications available elsewhere for your device. As per Section 9. Terms of Sale of the Terms of Use Agreement, there are NO REFUNDS ON DIGITAL GOODS, which includes this library.

Included File 01:

Included File 02:


Impulse Response Libraries
  • Acustica Audio N3
  • Fractal Audio Format
  • Line 6 Format
  • Wave Audio Format
Info & Support

Frequently Asked Questions
Frequency Discount
Privacy Policy
Terms of Use
About Us

Want to be informed of all the latest news, product releases, product updates, and sales events by email?

Join Our Newsletter