[RallyGuy]

Does any one have pictures of the Blu-tack Mod for the a900's? Looked all over head-fi and couldn't find one.

And yes, I did see the thread by tyson, but no pics were up.

Thanks

 

[RallyGuy]

Bump....These recessed mid's are killing me

 

[RallyGuy]

Pretty Please with a cherry on top???

 

[RallyGuy]

bumpity bump bump

 

[cheechoz]

What is the Blu-Tack mod?

 

[PMP'in]

do a search...

 

[cheechoz]

Quote:

Originally Posted by PMP'in do a search...

Very informative reply, maybe I'll do that!

 

[NotJeffBuckley]

Quote:

Originally Posted by cheechoz Very informative reply, maybe I'll do that!

I'll explain further. It's a mod that is doable to any closed headphone; you layer the interior of the enclosure with a thin, even layer of blue tack (sticky tack) and also attach a precisely cut piece of foam to the driver's magnet. The purpose is multifaceted; first, it deadens resonance that might otherwise occur. Second, it retunes the enclosure to have less air, resulting in slightly lessened very low bass response but hightened midbass and midrange response. Third, the foam kills standing waves.

It's a pretty neat modification, and I, too, would like to see the pictures of how it was done on Audio Technica A900, though I've no interest in doing it myself. The HD280-pro is another headphone which supposedly benefits greatly from this treatment.

Edit: PMP'in, this is a forum full of mostly nice people, and it really pays to be nice here. You don't want a reputation as a jerk hanging over everything you post. It took me less than two minutes to type this post, and you knew the answer as well. There's no reason to be rude - here's a truism that applies: "if you don't have anything nice to say, go jump in a river."

 

[BranMuffins]

Unfortunately I lost my pictures when I did this and no longer have my A900s.

This really is an easy mod to do that can have some really nice effects. Basically as has been said above is you take off the pads, take the drivers out of the cups, being careful to not to disconnect the wires. Then you remove the existing foam dampening and spread the blu-tak evenly on the cup. After that you use a few cotton balls pulled out to line the cups again. Then you put everything back together.

Honestly the hardest part is getting the pads off and then back on again with the A900s. There are a few other threads about this from when people have replaced their pads, just do a search. This thread also shows pictures of the driver and such.

Good luck and if you have anyother questions send me a pm.

 

[cheechoz]

I will make sure I hear a pair at the April National meet. When I had the A900 stock, the bass was rather resonant, and the mids where kind of recessed. Some may differ, but I think the benefits you spoke about, might be just the ticket for the A900's!

 

[iancraig10]

The idea of sticking Blutak to the inside of a headphone is fine if it works, but does the Blutak eventually come away from the headphone? If I use it to stick stuff to the wall, eventually, it comes down.

Ian

 

[HeavyBassMan]

I am interested in this mod, but I don't want to open up my A900s at all!!! Doing stuff like this just scares me.. I would hate to mess up the sound they already have, because I like them as they are. They sound perfect to me (even if I restore them back to the original A900s, I would not be happy that I've opened them up. I would have the thought I have done something wrong and my A900s have changed for good).

Has anyone just thought of using EQ for the mids? I don't seem to ever feel the mids are that recessed? Sometimes, I just lower the bass or something... but ONLY if needed on particular recordings. Also remember each artist, song, and recordings are always unique and are NEVER the same. Some were recorded digitally, others analogue, the artists could have had a bad day in the studio, or the mix was not quite right.... there are too many variables.

I sometmes change my EQ settings from track to track. This makes a huge difference in most cases. Especially when you shuffle your tracks around and listen to a variety of genre's, some hard rock/metal, then change over to Jazz, Dance, or Classical music. Using one set of headphones will not always work with different drastic changes in recordings, and styles of music. EQ can sometimes be very useful.

I am still keen to see just how easily the process works. From my searches, I found some threads where people were not too impressed by the mod at all, and even changed the A900s back!

I'd hate go through all that!

I love my A900's just the way they are, and I wouldn't change a thing! (hmmm sounds like i've fallen in love doesn't it! hehe).

 

[Chri5peed]

The A900s have garnered a reputation for sounding good, which is well deserved!

I can't imagine this sort of mod making a drastic improvement?

Is this blu-tak layer thin? I'd imagine anything thicker would make them significantly heavier?

 

[slwiser]

"Standing waves" inside a headphone cup? I have heard them cancel sound in my room with my surround sound system but in an ear cup where on fractions of an inch are in play? Sounds weird to me.

The standing wave is calculated using speed of sound (1130 fps) divided by twice the distance (in feet) between any two parallel sides (sides which could reflect a sound wave back onto itself). If there is as much as an quarter inch gap inside a phone with all the foam already there then you could calculate a standing wave above 50,000 Hz with that gap. For a standing wave to be as low as 22k Hz you would have to have two surfaces 0.61 inches apart. With all the foam already inside damping the reflections I doubt any "standing wave" is set up. But this does not mean it isn't! If the gap is less then the calculated frequency would only be higher. Would this drop out in the frequency be noticable above all the fundamentals? Has anyone checked the Headroom frequency charts to see if they have measured any significant drops in these frequency regions?

Quote:

Originally Posted by NotJeffBuckley Third, the foam kills standing waves.

 

[RallyGuy]

wow a lot of replies. Anyhoo, so really all you do then is open them up, and coat the driver in blu-tak? If this is how you do it, then how thick should the layer be?