thanks for your response and interest! at the moment my mobile flat has reached its limit so everything is very slow, will start more detailed posts after 4th of may. nevertheless i want to give you some idea of what i have done in this area.
after a while and trying to enhance bass quality and depth not only with custom bowls and venting the driver (usually all holes, it gives you the best speed, detail and soundstage i found the plastic housings to be the problem.
so i looked fore something round with different diameters, expandable in length, cheap and fitting the size requirements to load a grado driver. i also did some measurement about sizes of driver, bowls etc. and found a silly easy way to build a custom aluminium housing with variable size and diameter:
- simply fotofilter rings and adapters !
here is a picture of my latest mod, its a grado style headphone where i used the grado headband, parts of the cable and sr80i drivers (just today i replaced them with turbulent labs x drivers).
it is funny that a step up adapter 49mm to 52 mm has just the size to apply bowls or g-cushions on the 52mm side while the driver just fits stable on the 49mm side.
if you then add a 49mm filter ring, you have a replaceable driver unit, with the next additional 49mm filter ring also with a hole for the cable. to replace the driver with another one you just have to opeb the step up ring, solder a new driver with the cable and close it again.
afterr a step down adapter 52mm to 49mm you can add as much 52 mm filter ring up to the length were you find your best balance between bass, soundstage and imaging. at this point you can close the housing by just using a step up 49 to 52mm adapter
modded sr325is
or as i have done (see first picture) use step up and step down rings 52mm to 67mm to have the (whats the name for the ¨Gitter¨ ?metal part at the end closing the headphone, starting with sr225i made out of metal ??) Gitter covered with wood. (comment - i have leared now that gitter is metal mesh)
i wanted to get samething similar to the wooden sound of the big grados so i tried different kinds of wood finally choosing Balsa-Wood (In Germany called Balsa, its the i think lightest wood on earth and easy to manufacture, sounds great, easy to get it to resonate).
after trying to made rings with different technics i bought all the tools and learned to produce rings out a one single massive piece of wood.
So after you have built the aluminium housing out of rings, connect the cable, insert the wood rings, close the housing and you are ready to enjoy a great sounding grado style headphone with complete wooden inlay.
Thats all.
By the way the result is great sounding, you can´t hear even the smallest resonance or accoustical sign that there is a housing, just music around your head. as a short note, everything i did was crosschecked and listened to by to good friends who with no respect to any friendship gave me all the critics and points of improvement you need not to run into a single corner.
p.s. the typing errors are mainly caused by typing this whole post with my tablet, beg your pardon for that.
just wanted to post my latest 'photo filter adapters and rings' grado mod:
i used the following parts:
- beyerdynamic t50p headband
- 2 metal rings normally used to keep keys together
- a sr225i cable
- 2 bowls
- 2 sieves normally used for tea
- 2 sr80i drivers all holes vented
2x from driver to sieve:
- step up adapter 49mm to 55mm to put the bowls over
- step down adapter 52mm to 49mm
- step up adapter 49mm to 52mm
- step up adapter 52mm to 82mm
- step down adapter 82mm to 67mm
the result is an excellent sounding headphone with a rich and full bodied, more on the warm side sound, enough detail is there, but not even the smallest idea of harsh highs, nice bass extension, tight and controlled, and a very good soundstage width and depth. nevertheless it has this intimate grado sound, you are sitting first row.
the only point i think of is to add a ring of foam rubber to have sligthly more highs.
this is the continuation of my last post http://www.head-fi.org/t/119314/post-your-grado-mods/3300#post_9564376 with a more detailed description of the construction and some finetuning:
this is the driver side. the driver exactly fits between a step up adapter ring 49mm to 55mm, followed by a step down 52mm to 49mm and a step up 49mm to 52mm adapter ring.
the following step up 52mm to 82mm and a step down 82mm to 67mm adapter ring are then used to hold the sieve used as mesh. you can see that the metal (key)ring to hold the headband just fits into the slit between the two adapter rings.
this is a top view of the driver unit.
.
if you remove the step down 82mm to 67mm adapter ring, the sieve placed above the driver can be seen. i made a small slit in the outer ring of the sieve for the cable.
if you remove the sieve you can see the driver and how the cable is placed. in addition you can see two felt discs glued onto the driver, the inner one has holes on each side not to cover the driver magnet holes.
finetuning:
after some listening i found there were some bass resonances and also i wanted slighty more treble and detail.
i added a small foam rubber ring around the driver and
a large foam rubber ring to absorb resonances caused by reflections on the metal.
after placing the sieve in the middle and closing the driver unit with the step down 82mm to 67mm adapter ring the driver unit is ready.
i did this with both drivers. the result is an even more deep but dry bass, also treble and detail is increased to a level that while the overall sound is on the warm side the sound is coherent from the low to the top end ( beg your pardon for my limited ability to descibe sound in english words).
in one of my next posts i will write something more detailed about driver dampening an materials i tested.
Originally Posted by JoeDoe /img/forum/go_quote.gif
This Headphone looks really beautiful!
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.
