Orthodynamic Headphones & all things planar

[gurubhai]

You got yourself quite a catch buddy.
For those who don't know, Aiwa HP500 is also(like my NAD RP18) an OEM of Legendary Fostex T50 circa 1975 with a couple of differences. This one is much more efficient & is reported to work well even straight out of an ipod.
Also, the housing is quite different from the T50 with stainless steel, chrome paint & anodized finish.
The driver construction also has couple of differences regarding the trace density & the magnets used.

Here is a link for a recent review/measurements of Aiwa HP500 for those interested.

So Ananth, Any plans for a mini meet ?
Gotta see these beauties in person.:licklips:

 

[anm]

sure. will show up at your house maybe this weekend, not too sure about that so it would be a last moment plan.
The catch is all because of you. It indeed is quite efficient and I hardly move the knob of the amp before they start blasting. Will try with an ipod/ ipad some time.

 

[anm]

btw, I am Anant, not Ananth

 

[gurubhai]

^My Apologies.I actually know that your name doesn't end with 'h'.
Its just that i used to have a friend earlier who used to spell it that way, I guess the old habits die hard.

And it would be cool if you manage to drop by this weekend.

I have also purchased a new ortho, the PMB-80.

 

[anm]

which one is the left?

 

[gurubhai]

They are both the same. Bought them both but unfortunately one of these turned out to have faulty drivers.

 

[anm]

ohhh okkkk.

 

[gurubhai]

Some glamor shots of the Peerless PMB80 :

 

[Audiodoc]

Look good how do they sound. Most orthos are good throughout the midrange but they lack bass except the LCD2 which is in a class of its own. Textured bass hitting the lowest octaves.

 

[gurubhai]

^^Not quite true,it depends on the headphone.
My modded NAD's bass is every bit as good as the LCD-2.
The yamaha YH-100/YH1k are fabled for their bass response.
Even the humble HP50 has better(quantity & quality) bass than any other headphone I have heard apart from the aforementioned orthos.

Of course their are lower end orthos which have limited bass capabilities but one only gets what he paid for.

The PMB-80 itself is no bass monster though. I suppose it is comparable to DT880 600ohm that we have which is actually pretty decent.
The midrange bears the usual ortho excellence though its different sounding than the yamaha/fostex models.
The treble is nicely extended but their is a hint of grain here which I usually don't associate with planar drivers. perhaps it needs a little work.
The soundstage is wider than most vintage orthos which is good for a change.

 

[anm]

I have my amp in office so I am missing action at home. Any plans for a new amp?

 

[gurubhai]

^Perhaps. Come by & we can discuss it.

 

[anm]

I will call you
I know a visit is pending. Sat I have to be in office, sun I have to be at home for shraadh. But will try on either of these days, and I will NOT forget to bring along the headphone

 

[gurubhai]

Yamaha HP-1 Anisotropic variant

Introducing a rare version of yamaha HP-1, this one has anisotropic magnets which means 2 dB better sensitivity & supposedly better lower end.
Found it in NOS condition too.They look pretty nice for 35year old , don't they?

 

[anm]

hey - can I show up tomorrow early morning/ noon/ early evening?

 

[gurubhai]

Have some business in the evening but it would be great if you could drop by earlier in the day.

 

[iaudio]

Gurubhai, 35yr old NOS! Awesome! Now work your damping/tweaking magic on 'em.

 

[gurubhai]

Actually they sound pretty good stock!
They have a nice warm, mellow tone with slight mid-bass bloom & slightly sluggish transients. The vocals & mid-range are absolutely gorgeous.
Improvements from here on would be tough to implement & quite minor esp. for the genres (Jazz, vocal,bollywood oldies) that I usually use them for.

 

[Audiodoc]

The great thing is how you dig the hidden treasures of the internet! Thanks for the Aavids's this is how I used them. They are keeping the hot transistor cool enough now. The output transistors on the amp are still hot but within 60 degrees no I don't think I need to worry.

 

[gurubhai]

^The treasures do cost a hole in the pocket though, need to recover a bit & will be clearing some of my stash in next couple of months.

Nicely done doc!That delay circuit looks cool, where did you get it from?