JVC HA-S770. First over ear carbon nanotubes headphone.
Dec 9, 2012 at 1:15 PM Post #76 of 101
Quote:
Resonances and the problems derived from them won't disappear after  burn-in. But I believe that if you were succesuful modding the 750, the S770 shouldn't be a problem at all. Please document all the process so that we the less proficient can follow.

Partially true. The effect of burn in should principally be reduced frequency of the fundamental resonance of the driver, by making the suspension a bit softer after burn in. Other resonance(s) reamain of course the same. All the process will be documented to allow for reproduction.
 
I had actually much different post than this in mind, but what I hoped to be able to present with JVC HA-S770 unfortunately works correctly only with earspeakers requiring no pads at all ( Jecklin Float, AKG K 1000 ). As I have no intention of becoming a chain headphone buyer, I will try to use this new pair also to document burn in effects - something I hoped to pull off with the above that proved unusable with anything requiring earpads.
 
Luck has it that the Bruel & Kjaer representative for our country has his premises 15 min walk from my place. I will try to use "long eyelashes, high heels, fishnet stockings & any other charms imaginable" a guy in his early 50s can pull in order to try to get a quick measaurements confirming the effects of burn in "before"" and "after", that normally co$ts dearly, for free. IF they can do it at all - three months ago I was the first person in 30+ years history of B&K in ex Yugoslavia/now Slovenia, who inquired about artificial ear pinnas - no demand, no supply, those who are familiar with B & K prices will surely understand.
 
Otherwise, I will have to construct my own DIY ear coupler of some sort to be able to measure 770s with anything like even approaching correct results. Which means 770s have received zero playtime after recent unpleasent discovery and that is how it will remain until further notice pending the development of the events.
 
So, wish me luck for tomorrow's visit to B & K !
 
Dec 14, 2012 at 8:02 AM Post #77 of 101
Sorry for late update - busy with other audio stuff as well.
 
My "charms" were not good enough to get professional measurements for free, but did menage to get them done at not too exhorbitant cost - 150 EUR going down the drain come next Tuesday. New stock HA-S770s ( OK, say 3 h total playing time) , stock HA-S770s after 48 hours burn in using my method, then these HA-S770 modified as per description I will be posting in few days time.
 
I will post the ingredients for the recipe hopefully today ( have to get pics taken ), so that you can start little shopping spree - it should set you back by no more than 10-20 $/EUR.
 
It takes great discipline to be constantly only looking at new phones you are forbidden by yourself to  listen to prior...all the above; things we do for sound and better understanding how to further the sound quality...
 
Stay tuned !
 
Dec 14, 2012 at 8:43 AM Post #78 of 101
Thx for the effort AS, if you ever show up over here you are invited to "tapas y vinos".
 
Dec 14, 2012 at 9:24 AM Post #79 of 101
I'm starting to get interested. Wonder do the HM5 pad fit on these.
 
Will you take some pictures of the drivers and enclosure?
 
Unfortunately I can't get them anyway to start with
frown.gif
Nothing listed on ebay to Malaysia(where I'm from).
 
Dec 14, 2012 at 9:44 AM Post #80 of 101
Quote:
Thx for the effort AS, if you ever show up over here you are invited to "tapas y vinos".

OK - but not likely anytime soon.
 
There IS something I would like to have and is kind of one of the best kept secrets of ( audio ) Spain; where is it still possible to beg/borrow/buy/steal ( in a word: procure ) LPs from label Ensayo ? That single example I did get to hear, Satie's piano music arranged for orchestra by his friend Debussy, played by ..... ( it is 30 years by now.... ) Chamber Orchestra conducted by the female conductor Aviva Einhorn - is still unsurpassed for sheer musicality and recording techniques in my living memory. Acoustic Research, worldwide reknown loudspeaker manufacturer, sourced about half of the tracks for their demo LPs from Ensayo, the other half coming from BIS from Sweden, one of the most highly regarded labels for baroque music. BIS is somehow "available", an odd Ensayo LP gets listed from time to time on French ebay - other than that, nothing...
 
I just found that recording : http://www.ebay.com/itm/AVIVA-EINHORN-SATIE-DEBUSSY-ROUSSEL-POULENC-U-K-LP-/400114601437
 
No idea if it is originally Ensayo recording or not, ( it appears the same recording was issued on HNH label in the US, and probably on Amiga in France ...); I did get to listen to it on Ensayo LP and it was creme de la creme all the way...
 
Dec 14, 2012 at 12:00 PM Post #81 of 101
Quote:
I'm starting to get interested. Wonder do the HM5 pad fit on these.
 
Will you take some pictures of the drivers and enclosure?
 
Unfortunately I can't get them anyway to start with
frown.gif
Nothing listed on ebay to Malaysia(where I'm from).

Hi, UpsideDownCat ! ( Hope you don't mind ? - I absolutely adore your cat avatars )
 
There will be pics of everything. HM5 pads are round and 770s are "rectangularly oval" - when I get my HM5 pads will report if they fit, but you might ask dsnuts instead for instant gratification - he does have, or at least did have, JVC HA-M750, which is the same cup/earpad as 770. And HM5 pads on HA-S500s are his latest favourite.
 
I am afraid JVC's policy which models get to which markets is what it is - I got it from "local nearby EU France" , and magie-casques
 ( magic-headphones in "name translation" ) is still the only seller on ebay:
 
in white : http://www.ebay.de/itm/JVC-HA-S770-W-E-Casque-circum-aural-compact-et-pliable-Blanc-/221150093697?pt=FR_Image_son_Ecouteurs&hash=item337d92a181&_uhb=1#ht_3266wt_699
 
in black: http://www.ebay.de/itm/JVC-HA-S770-B-E-Casque-circum-aural-compact-et-pliable-Noir-/390492442675?pt=FR_Image_son_Ecouteurs&hash=item5aeb29d033&_uhb=1#ht_3776wt_699
 
Listings say shipping to Europe, but it can't hurt to ask if they can turn a blind eye every now and then ...! But I guess it might be pricey to your place.
 
OR - you can transplant drivers from HA-S500 into HA-M750 everything else = HA-S770; something I intended to do and JVC beat me to it.
 
Dec 14, 2012 at 12:31 PM Post #82 of 101
Quote:
OK - but not likely anytime soon.
 
There IS something I would like to have and is kind of one of the best kept secrets of ( audio ) Spain; where is it still possible to beg/borrow/buy/steal ( in a word: procure ) LPs from label Ensayo ? That single example I did get to hear, Satie's piano music arranged for orchestra by his friend Debussy, played by ..... ( it is 30 years by now.... ) Chamber Orchestra conducted by the female conductor Aviva Einhorn - is still unsurpassed for sheer musicality and recording techniques in my living memory. Acoustic Research, worldwide reknown loudspeaker manufacturer, sourced about half of the tracks for their demo LPs from Ensayo, the other half coming from BIS from Sweden, one of the most highly regarded labels for baroque music. BIS is somehow "available", an odd Ensayo LP gets listed from time to time on French ebay - other than that, nothing...
 
I just found that recording : http://www.ebay.com/itm/AVIVA-EINHORN-SATIE-DEBUSSY-ROUSSEL-POULENC-U-K-LP-/400114601437
 
No idea if it is originally Ensayo recording or not, ( it appears the same recording was issued on HNH label in the US, and probably on Amiga in France ...); I did get to listen to it on Ensayo LP and it was creme de la creme all the way...

I'll try to find where, if anywhere, these LPs can be found in Spain. There is a small but active second hand market for LPs here in Madrid. Also, I have several friends that own a quite extensive collection of classical music that includes vinyl (If they are willing, would be a copy in CD-audio acceptable for you?). Currently I am very busy finishing a couple of writing assignments... as soon as the holidays are over I'll begin the search.
 
Dec 14, 2012 at 1:44 PM Post #83 of 101
Quote:
Hi, UpsideDownCat ! ( Hope you don't mind ? - I absolutely adore your cat avatars )
 
There will be pics of everything. HM5 pads are round and 770s are "rectangularly oval" - when I get my HM5 pads will report if they fit, but you might ask dsnuts instead for instant gratification - he does have, or at least did have, JVC HA-M750, which is the same cup/earpad as 770. And HM5 pads on HA-S500s are his latest favourite.
 
I am afraid JVC's policy which models get to which markets is what it is - I got it from "local nearby EU France" , and magie-casques
 ( magic-headphones in "name translation" ) is still the only seller on ebay:
 
in white : http://www.ebay.de/itm/JVC-HA-S770-W-E-Casque-circum-aural-compact-et-pliable-Blanc-/221150093697?pt=FR_Image_son_Ecouteurs&hash=item337d92a181&_uhb=1#ht_3266wt_699
 
in black: http://www.ebay.de/itm/JVC-HA-S770-B-E-Casque-circum-aural-compact-et-pliable-Noir-/390492442675?pt=FR_Image_son_Ecouteurs&hash=item5aeb29d033&_uhb=1#ht_3776wt_699
 
Listings say shipping to Europe, but it can't hurt to ask if they can turn a blind eye every now and then ...! But I guess it might be pricey to your place.
 
OR - you can transplant drivers from HA-S500 into HA-M750 everything else = HA-S770; something I intended to do and JVC beat me to it.

 
Sure you can call me upsidedowncat :D
 
As for the S770, I've found some sellers in china that might ship to me but they price it at a premium. USD$130++ before shipping.
 
I have the brainwavz HM3 and HM5 on the way. HM5 were supposed to be "studio monitors". We'll see.
 
So yeah, I'm broke for now but I'll keep my eye on this thread.
 
Most probably pick up a pair from that ebay seller on January if he's willing to ship international.
 
Dec 14, 2012 at 1:50 PM Post #84 of 101
Quote:
I'll try to find where, if anywhere, these LPs can be found in Spain. There is a small but active second hand market for LPs here in Madrid. Also, I have several friends that own a quite extensive collection of classical music that includes vinyl (If they are willing, would be a copy in CD-audio acceptable for you?). Currently I am very busy finishing a couple of writing assignments... as soon as the holidays are over I'll begin the search.

Thank you for the reply. Take your time, finish your assignments first, of course; here we say: " Health first, culture second" ( unfortunarely, health is becoming ever more expensive over here too ... ).
 
Thanks for the offer of copying LPs to CDs, but the answer is - NO !!!!!! I found it to be a pure waste of time - with too little exceptions confirming this rule to ever bother further - sound is simply not acceptable, loss in quality is too great, to my analog ( and live...) spoiled ears at least.
 
I am working round the clock in order to get my Korg MR1000 DSD recorder ( which even in stock condition runs circles, alfas, omegas and whatnots around any 44,1/16 device as CD ) finally acceptable enough to start recording vynil I can no longer obtain ( or afford - chuckled at this one ... :
 
http://www.ebay.com/itm/Ravel-Ensayo-ENY-4-Victor-Martin-Marco-Scano-Zanetti-/110675854622?pt=Music_on_Vinyl&hash=item19c4cb851e )
 
in desired quality - and is known to be available with friends or acquaintances. The goal is to make this recorder sonically transparent enough to make difference when A/B ing sound from LP played live vs recording on Korg inaudible or at least not/barely worth mentioning - less than say between two phono cartridge models by the same manufacturer of the most close type/price within the range, not large(r) differences between entry level and flagship models. Stock Korg fails miserably at this test, yet it by FAR outperforms any CD recorder I have heard (of).
 
And, needless to say, I will put this recorder to my pro use as a recording engineeer ASAP !
 
Dec 14, 2012 at 4:13 PM Post #85 of 101
Quote:
 
Sure you can call me upsidedowncat :D
 
As for the S770, I've found some sellers in china that might ship to me but they price it at a premium. USD$130++ before shipping.
 
I have the brainwavz HM3 and HM5 on the way. HM5 were supposed to be "studio monitors". We'll see.
 
So yeah, I'm broke for now but I'll keep my eye on this thread.
 
Most probably pick up a pair from that ebay seller on January if he's willing to ship international.

Thank you, for officially allowing me to call you UpSideDownCat !
 
Ahem ... mentioning you have Brainwavz HM5 coming your way ( and going broke in the process ) - obviously you did miss mentioning these on HA-S500 thread :
 
http://jaycar.us/productView.asp?ID=AA2065&keywords=Pro+Monitor+Headphones&form=KEYWORD
 
2 pairs of HM5 earpads + headphones proper + case - exactly the same thing as Brainwavz, made by the same factory...if I were in market for yet another pair of "studio monitors", I would definitely go this way myself. Finances say go get HM5 pads only - pending what happens with 770s after the mod - potential sure is there. But I am determined to get 770 going - or else I would not be willing to pay for the merasurements alone about the equivalent of 770s and Jaycars shipped to my place - combined !
 
World economy sure works misterious ways - JVC HA-S400 $ 18 SHIPPED in USA (within USA), JVC HA-S770 130 $ +++ from China - it really pays to "click" more than a couple of times before really pulling the trigger.
 
Dec 14, 2012 at 6:00 PM Post #86 of 101
So, here the ingredients for my recipe : non slip mats, double sided tape, blue tack or similar :
 
 

 
Please note the difference in size(s) and patterns; EAN of the black roll "clearly" visible, pattern for the black roll and "flower" being identical
 

 
Open "flower" : blue, black, white, purple/red : EAN for "flower" is 6902086586888 ; EAN for larger grey mat is 6935331265894 ; again, note the difference in thickness, size and pattern
 

 
The almost industrial size for " blue tack "  that is actually white ( half of the 2 kg roll already gone ... )
 

 
Size comparison -  2 Euro coin
 
A tip - you are most likely to get these non-slip mats in 1 Euro/ 1 $ shops carrying mostly chinese stuff; nowhere else could I find the thin small fine pattern non slip mats, everything I could find in "normal" shops was usually the size of the grey mat pictured or larger. Try to get the most soft and pliable/souple stuff you can find; the grey mat is already a bit too hard for my liking and will try to improve on that, but not at all costs ( like paying say EUR 30 for a package of slightly softer mat that would allow for about 100 pairs of HPs to be modified ), as extremely small amount is needed, say 80 % of the requirement is the thin small fine pattern mat. For the "blue tack" - in Europe, UHU Patafix 
 
http://www.uhu.com/en/products/glue-pads.html
 
should be readily available almost in any country and is reasonably priced. Other continets - feel free to improvise a bit. For double sided tape I used product from Tesa that is white and is of acceptable quality for the job; the best is a no name no nothing transparent one from a 1 Euro shop made you-know-where; that one conforms very nicely to the irregular shapes of the insides of various earcups, so have your eyes peeled for something in this direction. The mod I am going to describe is reversible and you are not going to have to make any permanent non reversible changes. Tools required are a pair of sharp (curved) scissors and a sharp blade, preferrably xacto (or equivalent from 1 $ / EUR shop ) # 11.
 
Please note that small/fine/uneven pattern "flowers" show EXTREMELY LARGE VARIATION IN THICKNESS/OPENESS/WEIGHT - although of the exactly same area, they go from just a hair above 2 grammes per mat to the same hair below 7 grammes - that is almost 350 % difference ! That means you will have to get either rolls ( that are more consistent ) or more of the "flowers" in order to make the selection; it would be inappropriate to try modding left channel with a 2 gram and right one with a 7 gram "flower" - the preliminary measurements I took indicate very close channel matching in 770s and you do not want to make it worse. If you do not have scales capable of reasonably accurately measuring 10 gram ( or less ) objects - local pharmacy might be kind enough to weigh them for you.
 
Happy hunting !
 
Dec 24, 2012 at 11:51 AM Post #87 of 101
Spent the better part of the day with the representative of Bruel & Kjaer for our country - measuring HA-S770 and HA-S500 in slightly modified condition using ATH velour pads. Graphs etc when processed, next session with "B&K" scheduled for thursday afternoon, to give me time to perform my 48 hour burn in sequence and it will be done so that re-measurement can be made on thursday afternoon. 
 
Our ears did not lie, measurements for stock HA-S770s are appaling, like +12 -12 dB limits - HA-S500 is incomparably smoother. Measured were frequency response from 10 Hz to 25 kHz and response to square wave at 30 Hz and 300 Hz. Interesting is that carbon nanotube driver does not roll-off in the treble - there is a notch  ( from memory ) at about 20 kHz - then it picks up to almost reaching 0 dB at 25 kHz, which is the limit of the Bruel & Kjaer
artificial ear used ( exact type designation will be given together with graphs etc ).
 
Merry Christmas ( to everyone who celebrate it ) !
 
Dec 24, 2012 at 12:34 PM Post #88 of 101
Spent the better part of the day with the representative of Bruel & Kjaer for our country - measuring HA-S770 and HA-S500 in slightly modified condition using ATH velour pads. Graphs etc when processed, next session with "B&K" scheduled for thursday afternoon, to give me time to perform my 48 hour burn in sequence and it will be done so that re-measurement can be made on thursday afternoon. 

Our ears did not lie, measurements for stock HA-S770s are appaling, like +12 -12 dB limits - HA-S500 is incomparably smoother. Measured were frequency response from 10 Hz to 25 kHz and response to square wave at 30 Hz and 300 Hz. Interesting is that carbon nanotube driver does not roll-off in the treble - there is a notch  ( from memory ) at about 20 kHz - then it picks up to almost reaching 0 dB at 25 kHz, which is the limit of the Bruel & Kjaer
artificial ear used ( exact type designation will be given together with graphs etc ).

Merry Christmas ( to everyone who celebrate it ) !
Thanks for the graphs! We will appreciate them! :xf_eek:
 
Dec 25, 2012 at 9:10 AM Post #89 of 101
48 hour burn-in process using http://www.head-fi.org/t/625840/controlled-burn-in-with-predictable-results-for-headphones started a couple of minutes ago, as I want it to be finished exactly at the time scheduled to repeat the measurements of JVC HA-S770 after this burn in. Prior to start of the burn in process, this pair had about 3-4 hour music played max plus the time of the measurements - together, effective measurement play time should not exceed one hour ( I have recordings of the test  signals for the duration of the entire session and can check for  the exact time, but should be there about ) - so, it is fair to assume that this pair was not used for more than 5 hours of "normal" music - I have specifically avoided anything that would be otherwise used for burn in, that is to say anything very loud and/or with great amount of low bass.
 
Minutes ago, signals from where 
very_evil_smiley.gif
evil_smiley.gif
 has the upper hand, were unleashed on the 770s. That guy is smart enough not to torture them to destruction - believe me, I am more curious than you what measurements in two days time will reveal !
 
Dec 29, 2012 at 4:44 AM Post #90 of 101
Analogsurviver.
 
Thx a lot for all the effort and keeping us informed of such an interesting process. As soon as the holidays are over I'll try to "follow on your steps" and save my 770s from the hell-box of forgotten headphones.
 
I have a couple of side-related questions. I am trying to follow your instructions to burn-in the S500. Could you tell me where you established  the resonance frequency for these headphones. I am following you method as described in the other thread, but I get confused and after an hour I am starting to fear for my hearing.
 
Second question, how do you produce a Square-Wave with Sinegen? There are no instructions on the web and the program isn't very self-explanatory. May be is just that I am a little dumb.
 

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