[maverickronin]

So you've turned the LHC into a speaker system?

 

[nickchen]

Quote:

???  The issue with 'stats is the amps or energizers.  They definitely have a different sound signature than the vintage orthos even after tuning and mods, but I can't say I like one beter than the other.  My 1974 Lambdas off an eXStatA are simply superb.  The Lambdas are my best bang for the buck can I own with my 001s shortly behind them, but I put $170 custom tips on them so they cost more than my Lambdas.  Most O2s off great amps toe up to the borderline of having too much bass for many listeners.  The drawback to 'stats is that they really do scale with investment and they aren't necessarily cheap, but you can build a grat budget 'stat system with patience and persistance.  I run my Lambdas primarily off a Yamaha CR-620 receiver feeding a SRD-6 normal bias only energizer.  The transformers in the energizer strip away the lower octave and roll off the second octave, but it's easily corrected with +2 or +3 on the bass and a little tweak to the loudness dial.  I have less than $450 in the whole setup, but I was given a Good Karma price on my Lambdas and I traded a lawn mower for the Yamaha.  The SRD-6 was $60.  Real world, the CR-620 is a $150-$200 receiver, the Lambdas are $275-$350, and the SRD-6 is in the $75 range.  So you can get into a decent 'stat setup for $500-$600 total with the added benefit of being able to easily drive any ortho or dynamic off the headphone jacks and run 89dB or higher efficient speakers with plenty of volume for most listening levels.  Oh, and the phono stage in the Yammie receiver is quite good too, better than any sub-$300 stage I've heard yet.  One of these days I'll mod the Yammie a little with some critical resistor replacements and probably some TDK pots.  Then replace all the electrolytic caps and I'll have one helluva amp.  My DIY energizer will restore the missing bass to the Lambdas too, but I'll soon have the first prototype of the Liquid Lightning amp built soon and then after some mods it will be my Magnum Opus dedicated 'stat amp and it will be great, but it will cost as much or more than a set of the new 009s so it's definitely not a budget system. 
 

I wasn't completely serious about this, and I do know that at least the old Lambda Pros can sound pretty terrific. But I still find 9 of 10 Staxes simply boring (the same is to be applied to the HD800 BTW).
 
I'm on a constant search for best-as-possible musicality, other stuff like audiophile merits are partly subordinate for me personally.

 
 

 

[ardgedee]

Quote:

Here's a picture of my crew setting up my new speakers.  Once they get it into my house, which you can see in the distance, they're going to drill holes in it and slap a diaphragm in there.  I'll let you know my impressions. 
 

That's just one of the satellite speakers, right? You're not going to use something that puny for the main forwards, are you?

 

[GrandZechs]

Quote:

Thanks for stepping in, BMF. I did a quick webwide search but found no 32-ohm SFI "bipoles" left. Which is sad.

Yes thanks! I've looked for a week with no luck. I'm glad there are great people here with some to spare! Now I just have to wait for my Stanton Fifty's to get here and start modding away. I'll keep ya updated on my first project.

 

[Inkmo]

well of course you guys couldn't find any.  BMF bought 'em all XD

 

[Antistase]

Damped my hp1 today. 100% wool thin felt on the back of the driver, blue tack on the back of the cup, thicker lighter 100% wool felt on top of the blue tack and the original foam in between the two felt disks. I added also 4 microporous reflection disks directly on the back of the driver under the felt and sealed the driver with blue tack against the baffle. I managed to leave the original pads in place as they are in excellent conditions. The thick felt I'm using has very low density and is covering the vent felts too.
Nice result so far with the only major casualty of that little bit of ss that was there originally.
Way much better than stock. Still the mid low honk doesn't seem to be tamed and I would like to extend the HF a little bit higher. Anyone having suggestions about it? Somebody is a specialist about reflection dots? Is it better to use more sealing and reflective material for them (e.g. copper tape). Any specific reflection dots pattern that worked best for you with this headphone? I want to act only on the rolloff keeping the rest of the hf at the same level as they mingle beatifully wit the mids. Is there a relation between the dimension of the dots and the reflected frequency?
I've ordered already some fish foam 2cm thick to replace the original one.
 
Also is there a final consensus about the value of recabling this can? My usual way would be mogami with nylon sleeves.
 
Thanks to everybody.

 

[scompton]

I listened to the T30 with XB700 pads for about 5 hours today.  At about 4 hours, the edges of my ears were feeling just a little irritated.  Moving the pads a couple of mm would fix it.  I ended up having to  move it around a couple of times in the last hour.   All in all, I consider that a pretty good result since with the stock pads I doubt if I ever listened to the for more than a half an hour.
 
Antistase, the low mids honk sounds like they're still slightly under damped.  What material are the microporous disks?  Are the 3M Micropore tape?  If so, you may need to cover more of the back of the driver with it, or try denser felt.  I can't suggest anything for the treble.  My HF hearing is good for a 51 year old, but it's not all there anymore.

 

[Teejaay]

Quote:

I listened to the T30 with XB700 pads for about 5 hours today.  At about 4 hours, the edges of my ears were feeling just a little irritated.  Moving the pads a couple of mm would fix it.  I ended up having to  move it around a couple of times in the last hour.   All in all, I consider that a pretty good result since with the stock pads I doubt if I ever listened to the for more than a half an hour.
 
Antistase, the low mids honk sounds like they're still slightly under damped.  What material are the microporous disks?  Are the 3M Micropore tape?  If so, you may need to cover more of the back of the driver with it, or try denser felt.  I can't suggest anything for the treble.  My HF hearing is good for a 51 year old, but it's not all there anymore.

if you want take away the brightness try
 
trans | micro | trans
micro | blank | micro
trans |micro  | trans
 

 

[wualta]

 
Quote:

So you've turned the LHC into a speaker system?

 
Headphones too, with flux left over. Heck, with magnets that size in the room, you wouldn't need to carry 'em on your head. Ask Kabeer sometime about the magnetless orthos a doctor designed to soothe patients while inside an MRI scanner.
 
Quote:

Damped my hp1 today. 100% wool thin felt on the back of the driver, blue tack on the back of the cup, thicker lighter 100% wool felt on top of the blue tack and the original foam in between the two felt disks. I added also 4 microporous reflection disks directly on the back of the driver under the felt and sealed the driver with blue tack against the baffle. I managed to leave the original pads in place as they are in excellent conditions. The thick felt I'm using has very low density and is covering the vent felts too.
Nice result so far with the only major casualty of that little bit of ss that was there originally.
Still the mid low honk doesn't seem to be tamed and I would like to extend the HF a little bit higher. Anyone having suggestions about it? Somebody is a specialist about reflection dots? Is it better to use more sealing and reflective material for them (e.g. copper tape). Any specific reflection dots pattern that worked best for you with this headphone? I want to act only on the rolloff keeping the rest of the hf at the same level as they mingle beatifully wit the mids. Is there a relation between the dimension of the dots and the reflected frequency?
 
Also is there a final consensus about the value of recabling this can? My usual way would be mogami with nylon sleeves.
 

Not sure what you mean by "mid-low honk", but if by that you mean that there's a lump in the midbass where it meets the midrange, you might need to use denser felt right behind the driver-- ie, you may need to increase the amount of damping. Always get this part right before you take care of anything else, even the top end.
 
Which brings us to reflex dots, but let's use the euphemism "reflection discs". To answer your question, yes, the effect of a reflection disc is very much dependent on its size.
 
Reflection discs have become anathema in some quarters, so prepare to be shunned if you use them. Their use was originally intended to prop up only the top two octaves (5k to 20k). The theory goes like this: A disc of a certain diameter will let sound wavelengths greater than that diameter diffract, or bend, around the disc. Wavelengths shorter than the diameter of the disc will reflect back, adding to the original sound, since the reflection point is virtually on the diaphragm itself. In real life there's no sharp cutoff-- as frequency rises from the bass, a reflector disc will reflect nothing, then a little, then there will be a more sudden increase around the point where the sound wavelength matches the diameter of the disc, then back to a gradual rise to a shelf or plateau after that. In speakers there's an analogous (but reverse) phenomenon called the "baffle step".
 
Or in ballet, the pas de baffle. But that's not important now.
 
By combining porous tape (MicroPore, TransPore) with felt, you might be able to make a reflector large enough to reach down to the point where the dreaded Ortho Droop begins (according to Yamaha's response graphs, this could be as low as 1kHz !) without sealing the driver and creating a tweeter. And to do this right, you'll want to experiment with several disc sizes. Try a whole bunch of little ones. Or one big one (maybe 19mm or so) smack in the middle. Then add a circle of little ones orbiting around the big one. Since the ear is not omnidirectional at all frequencies, some experimentation (and research) is in order, because it may be possible to cheat. I love it when that happens.
 
Of course, since the traditional treble control hinges at about 1kHz, you might just want to take the easy way out and do the correction electronically. It's only about a 3dB/octave slope, so nothing radical is needed.
 

 

[scompton]

Quote:

if you want take away the brightness try
 
trans | micro | trans
micro | blank | micro
trans |micro  | trans
 

Was this directed at me?  The T30 isn't bright.  The irritation is from the pads rubbing against my ear lobes, probably with a little hair thrown in for extra irritation.  It also is vintage so doesn't have the new square Fostex drivers.  I'm not sure when exactly mine are from, but they were made from the 70s to the 90s, introduced with the original lineup and phased out just before the RP line came out.

 

[wualta]

I'm not sure how long the T30 stayed in the line. I was still able to buy one here in west Michigan for my employer circa 1985, but I doubt they hung around much beyond that, since as we know they were possibly the least comfortable headphones ever sold by a pro audio maker, and that makes me doubly glad that those poofy earpads not only make the T30 wearable by humans but also undarken the sound a little.

 

[clc77]

Hi, I just purchased some SFI 120 ohm drivers. Are there any projects/guides anywhere that suggest a frame and damping scheme? Thanks

 

[scompton]

I just did some test tones the the T30, the top end starts rolling of at 10k Hz and is gone by 13k Hz.  The low end starts rolling off at 70 Hz and disappears at 25 Hz.  This is listening at 65dB, volume nob at 10 o'clock on my Shiit Asgard.  When I turn the volume up to 12 o'clock, which I know is a level more people listen at, the I stop hearing the bass at 15Hz and the treble extends to 15k Hz.

 

[scompton]

Quote:

I'm not sure how long the T30 stayed in the line. I was still able to buy one here in west Michigan for my employer circa 1985, but I doubt they hung around much beyond that, since as we know they were possibly the least comfortable headphones ever sold by a pro audio maker, and that makes me doubly glad that those poofy earpads not only make the T30 wearable by humans but also undarken the sound a little.

I thought I read they were produced into the 90s.  I'm probably misremembering.   They are in the 86 brochure I have along with the T20v1 and T10.
 
Edit:  I imagine it was torture working in the studio where Eric got his T30s.  I can't imagine to many studios were happy with their purchase which is probably why they're so rare now.
 


Quote:

Hi, I just purchased some SFI 120 ohm drivers. Are there any projects/guides anywhere that suggest a frame and damping scheme? Thanks

 
I thought I had ludoo's search engine bookmarked.  If someone can post the link to that, you'll be able to search this thread.
 
 

 

[dBel84]

first post in this thread - wualta did us all a favour and edited his post ( many times over aka the true curator of all things ortho ) ..dB