After a long time of not beeing active in this thread i wanted to post my latest grado mod i did some month ago:
based on a very similar mod i posted before with sr80i drivers i wanted to do a kind of final mod optimized for
- soundstage
- bass quality and depth
- linearity
- better drivers for improved highs, resolution, imaging and detail
as i did not want to disassemble another headphone with sr325is drivers, i bought two turbulent lab X drivers for this headphone (all holes vented):
as usual the complete aluminium housing is made out of photo filter rings and adaptors, here you see both sides of the headphone:
This time i used two small tea filters as mesh:
i used a sr225i 8 wire grado cable, removed the outer cable sheath on both sides of the y-split and used some shrink-on tube to apply the new one:
This time i made a complete inner balsa wood sleeve from driver to mesh:
the ring and wooden sleeve around the mesh improves soundstage width, in the same time the precision and quality of both bass and highs, but the overall sound slighty moves to the brighter side and the higher the ring around the mesh, the more 2 dimensional the soundstage will be, you loose soundstage depth, so some testing and listening required to find a good compromise:
i spent a lot of time optimizing the wooden parts. for example the inner sleeve's thickness and shape is important for a good balance between bass and high frequencies, the best solution was a sleeve with round inner shape you can see here:
at first i had the problem that i missed soundstage depth when the rings around the mesh were just ideal for the overall precision and soundstage width until i learned that the soundstage depth can be improved and adjusted by a wooden disc above the driver so not only damping the driver with one felt disc. after a lot of testing and listening i found this combination as optimum. if you add too much length here you loose precision, the highs are absorbed and also soundstage width is decreased.
Also you can see the filter rings filled with a foam rubber ring to have a resonant free and fixed contact between alumininium housing and wooden sleeve:
the complete headphone can be disassembled, the only fixed connections are the four soldering points for the drivers:
soundwise, the resulting headphone is very linear from top to bottom end, has a very deep and precise, highly textured bass and also a really good resolution, imaging and fine detail, i think limited by the Turbulent Lab X drivers. the imaging is slightly less pinpoint-like than my t5p or the hd800.
the soundstage is clearly wider than the soundstage of my hd800, the overall presentation nevertheless is more grado-like, you are sitting first row, all the objects are slightly larger as when listening with the hd800, where i have the feeling to sit in the 10th row.
For me this is my perfect headphone (at the moment?) as it has the soundstage, bass quality and depth i always wanted but nevertheless sounds like a grado. the only point of improvement i could think of at the moment is to implement some sr325is drivers or to wait until i get my hands on some rs1i drivers.
Interestingly i have stopped modding grados as i am really happy now.
but
- last week bought and extracted the drivers of an iGrado to build a low cost low weight portable open grado
- and i made and had a prototype of a CLOSED grado running with no sound degradation compared to an open one so now i know how to do it but have to improve my manufacturing skills to build something i can post here.