Quote:
The G-Cush pads increase HF dispersion in two ways. First, closer ear-driver distance actually mutes HF and accentuates the midrange. With flats and comfies, this is a good way to hold onto the bass, which is why the SR60 traditionally had the best bass response of any Prestige Grado south of the SR325 while the SR80 (which originally differed from the 60 in having bowls instead of comfies) had the least bass of any Grado, period. Second, the wider mouth of the G-Cush pads improved HF dispersion, which is curious since HF waves tend to be more directional while LF waves tend to radiate more (which is one reason having a hole in the back of your headphone tends to affect the bass). I've come to the conclusion that the spongy material absorbs HF, creating a moderate damping effect.
Whatever the reason, jumbo pads tend to shift the tonal balance brighter. You get more HF, an airy treble that predominates. Bass, on the other hand, gets washed out. While there may be something to the idea that longer LF waves benefit from distance, the spongey material of Grado pads leaks sound rather than reflecting it. Other materials - including leather, nagahyde and velour - have a different effect on the sound. Thicker material affects the sound differently from thinner, more transparent, material. Grado cushions are designed with transparency in mind. They leak sound in order to avoid reflecting it and producing a muddy resonance, which is what you'll get from a number of more reflective materials. But the more you lengthen the cushion, the more bass you lose and the more sibilant the presentation feels.
Mind blown. Feels good brah. Guess I won't be getting those xD
Here's what you do.
1. Open the cups and vent the drivers (punch all ten holes to really unleash the tiger by increasing the airflow).
2. Damp the magnet back with something like Dynamat or BluTack.
3. Remove the plastic button from the back as it bounces HF waves right back into the presentation.
4. Remove the plastic ring stuck near the rear grill as it has no use and adds unwanted resonance.
If you will make these mods, your 325 will become the Voice of God. You will not be able to take it off. You will lose sleep because you won't want to stop listening to your music. I did this and was completely and utterly blown away.
People already say the 325 is too brash (which it is unamped) but with these mods, you'll get the bass you need to shift the tonal balance back to center while removing certain jarring spikes from the presentation. It's in this context that you can add the jumbos. Without these mods, the jumbos will just feel too bright and bass anemic.