[thelostMIDrange]

Ok I see what you are saying strat. Maybe oil the distancer between driver and ear but not eh back side of cup....interesting.....but i would then have to live with the affects of the driver being further away from the ear. which may be ok if in the trade I could get this mid compression without it ruining the bass...

 

[thelostMIDrange]

yes the percent of coverage changes everything, but I haven't noticed it changeing things disproportionately for different frequencies....I don't think I could pick up on that even if it were happening......too bad i can't just coat part of the cup and not another.....I guess nothing's that easy.

 

[thelostMIDrange]

what if I taped off interval bands lengthwise and wiped the oil over the entire cup, then when it dries, take the tape off to reveal raw wood under those sections.....something like that.......maybe this would then affect the lows differently.........anything to keep the oil from affecting the lows

 

[liamstrain]

that sounds like a reasonable plan to try, if you have the spare time and cups... 

 

[thelostMIDrange]

just to be clear stratocaster, the oil is not affecting the quantity of bass, it's affecting the quality... in a negative way.....but the affect on everything from low mids up is very nice. It's the same quality, it just doesn't serve the low end well for whatever reason

 

[thelostMIDrange]

I can try it because if it doesn't work its' just a quick wetsand and the oil will disappear and i'm back to raw wood,,

 

[thelostMIDrange]

applied danish oil to inner walls with 3 strips approx .5" wide each blocked out to leave raw wood. No idea why but it's wonderful. This will be the final solution for me. The most noticeable and beneficial change is how realistic and natural everything from vocals up is. I've never heard hi hats and cymbals as realistic and natural in limba before. What a nice atmosphere. Everything is placed in space and has it's own character. Don't know if it's the type of oil or the oil/raw wood pattern. And the best part is that the bass seems unaffected. I can't find fault. I only hope I can replicate this delicate balance on another set. Should be able to since I know exactly what was done, but that final oil application is super critical and delicate it seems. The type, amount and placement of the oil seems to affect things alot more than I wish it did......

 

[sluker]

Did you leave the outer walls bare?

 

[thelostMIDrange]

outside is the shelac......but the inner surface can change the entire character and placement of sound.....with the oils, the mids and treble jump out from the background. This was one of my two complaints with raw limba sound. One was the unrefined upper end (characteristic of all raw wood sounds) and the other was the background placement of vocals and hit hat's and other cymbals which also would have been a deal breaker since these need to be right up front for world class sound that has emotional impact....

 

[thelostMIDrange]

But I think I need to do a double oil on the inner surface since that is what I have here.....yesterday I oiled the entire surface with truoil and then wetsanded 90% of it away......on top of that i did the striped danish oil treatment with a much lighter wetsand.I'd say 90% of that oil is left in this final sound......so it will have to be a 2 stage inner treatment....and this is not including the outer surfacw which is a different treatment entirely and does seem to be nicer than the oil's I had used in the past......now whether I could just use one of those two oils on the inner insted of both, I don't know, but they seem to sound different from each other so at this point, since I still have both oils, I will follow what I did here......

 

[thelostMIDrange]

and these cups were tuned with the 2 hour fresh drivers....they sound like totally broken in drivers to me. Rich and warm with character and detail. wonderful atmosphere and instrument placement....this all leads me to believe that driver burn in is minimal........cup tuning is powerful stuff. too powerful. Wish it were not so. would makes things much easier

 

[thelostMIDrange]

If I have a quibble with the current sound is that I've heard bass guitars a little more defined in some other final finishes.....I recall this being early on in the process when was using danish oil, so will try a simple danish oil inner wetsanded next time first and then dial it in as needed with the striped oil method. It may turn out that the danish oil inner is primarily causing the pleasing results here which would be nice because then it could be a one step interior finish process. But cup geometry and outside surface is pretty much set in stone at this point. The inner surface could be tailored to particular person's preference and music collection. The truoil seems to have more compression compared to danish. I think there's still more to learn about those two oils and their affect as an inner wall treatment, but at the very least, both work much more than any other finish i've tried. and they can be wetsanded to desired affect pretty easily compared to other finishes which are more invasive and less maliable....

 

[liamstrain]

I'm glad the striped method worked. Yay theory backed by experiment. 

 

[thelostMIDrange]

I haven't ruled out the different oil yet as the factor for the change though. The oils sound different amazingly enough. I may even try a blend and see what happens.......the inner surface is a whole world of exploration in itself it seems. And to think most people still think all woods sound pretty much the same. I would never even begin to convince them that the inner surface matters......Live and let live though. to each his own. ignorance is bliss. etc.......
 
 
in fact the inner surface matters so much I was having l/r balance issues and thought it was driver mismatch but turnes out it was likely the slight difference of inner treatment. It's almost impossible to get them the same on the first try. the same amount of oil and wetsanding.......they must be listened to and wetsanded until they sound even and the same.

 

[thelostMIDrange]

topic:Oversized 'buttons' on the exit port hole
 
 
point - you know those little plastic buttons on some grados....it's known they affect things a little
 
counterpoint A  - When I cupped the end of my old grados (completely) in plastic, mahog and aluminum, the changes were drastic and generally non-musical. raised or lowered the pitch, made sound unatural etc. You can also feel the pressure of the sound waves getting 'backed up' against your ears. Sound waves are powerful stuff.
 
counterpoint B - when I cup the ends of my tuned cups, the change is far less drastic and still somewhat musical. I wouldn't want to leave the ends closed but it got me thinking about those little grado buttons and I suspected once the cup was tuned, they might be useful, since the sound is generated around the edges of the driver, not out of the magnet. So it really starts its journey there.
 
Synthesis - So I made several sizes of end caps 1/2" 3/4" and 1" ..........the effective opening of the cup was 1.5"
the half inchers had very little if any noticeable affect, the next two did however and the 1" seemed to really bring the vocals more up front and focused the sound a touch and whenever this happens the intimacy level goes up., which my limba cups benefited from. So really there was only 1/4" opening around the edge.
 
So I will making a set with wood end caps and 1/4" edge opening. 
 
 
Another experiment involved the placement of 3/4" dowel rod right up against the magnet back and straight out through the back of the cups, effectively making a solid cylander separating the outer edge soundwaves, the entire length of the cup. You would think this would totally mess with the sound and it would be terrible since there is a big rod in the center of the cup the entire length .....but suprisingly I noticed very little affect, negative or postive -about as much affect as the simple 3/4"button on the end............ Which tells me most of the action of sound is within the 1/4" or so around the cups inner edge. and this of course adds some explanation as to why the finish is such a powerful influencer. The sound is bouncing and riding that edge all it's journey from back of driver to outside the back cup edge......... 
 
 
But it also led me to the 1" end cap idea. which if useable, would also serve to negate the need for the mesh grill since with only 1/4" gap around the edge it's pretty tough to see anything unsightly inside the cup such as the wires etc.....I never liked those grills in any case....will see.