[davidsh]

It's a transformer.. Like all the others I suppose?

 

[eric65]

Better, much better, because optimized (coupled to an amplifier OTL as the RKV-II amp).
 
Otherwise, leave your preconceptions about RKV amp and Verto box, otherwise you will miss something very interesting to listen.
 
PS :
Verto box (normal version) with 1:5.9 optimized transformers.
Verto box mk2 (hypothetical version) with switchable transformers for even greater transparency and definition.

 

[arnaud]

And, it's hypothetically the best amplifier in the world! eh

 

[David1961]

IMO, Eric's posts will be great to read for those that suffer with insomnia.

 

[eric65]

  And, it's hypothetically the best amplifier in the world! eh

 
Well, Arnaud, I speak here of the combo RKV-Verto.
 
Indeed, the "MK2 version" of the Verto box (with its switchable transformers) is, to date, hypothetical.
Maybe you'll see one day, who knows?. I work for this purpose.
 
On the other hand, the experimental version of Wee (Eric65 moded) is real, and its transparency, presence, definition and precision are formidable; competing amps: well must be held !
 
Finally, the versatility of the Verto (even more with a mk2 version) is unparalleled: try to drive an Ortho or electrodynamics headphone with an amplifier Stax, you tell me the news.
 
 
PS : the best combo in the world ? (and also the more expensive). No.
 
Instead, look toward Sennheiser and the release of a (hypothetical) system Orpheus mk2 in 2015 for the seventieth anniversary of the brand.

 

[RiStaR]

I think why everyone is tiring is because you're continually pushing RKV stuff... It's like you're working for them?

 

[eric65]

I'm a simple amateur. I work pro bono.
My profession is doctor.
No harm to speak well of something good, I hope? 

 

[RiStaR]

  I'm a simple amateur. I work pro bono.
My profession is doctor.
No harm to speak well of something good, I hope? 

 
Well... look at it this way. If you think something is good you want it to do well. What do you think is happening with the way you're approaching this now? Don't you see that you're potentially harming RKV more than you're helping it?
 
You're basically yelling at a group of folks who have owned Stax gear for so long and have gone through all the amplifier upgrades available (and KG has designed so many of them). You come yelling without any measurements but your ears and you demand to be taken seriously. You're not creating a religion here... everyone has their own ears in this case.
 
Anyways, we get it. RKV is the best Stax amp you've heard. Period. Just like the Megatron is the best Stax amp I've heard. There's little need to regurgitate so many times that everyone does not want to know anything more about RKV. So it's no longer pro bono, if you think about it. It can be argued that you're a cost-centre [after my last post I just chanced upon your other thread.] instead of just 50 Euro... you're costing them potential business.
 
Anyways no offence man... just trying to lay it out for you and basically to let you know that chilling out a tad on RKV stuff may bring you closer to your goal... I remember this quote from Ghandi ..."In a gentle way, you can shake the world." I'm sharing that with you... just cause I think it makes sense here in this case.

 

[paradoxper]

  I'm a simple amateur. I work pro bono.
My profession is doctor.
No harm to speak well of something good, I hope? @

 
Discounts! DIscounts!! DISCOUNTS!!!

 

[eric65]

  I'm a simple amateur. I work pro bono.
My profession is doctor.
No harm to speak well of something good, I hope? 

 
 
Originally Posted by RiStaR /img/forum/go_quote.gif
 
 
Well... look at it this way. If you think something is good you want it to do well. What do you think is happening with the way you're approaching this now? Don't you see that you're potentially harming RKV more than you're helping it?
 
You're basically yelling at a group of folks who have owned Stax gear for so long and have gone through all the amplifier upgrades available (and KG has designed so many of them). You come yelling without any measurements but your ears and you demand to be taken seriously. You're not creating a religion here... everyone has their own ears in this case.
 
Anyways, we get it. RKV is the best Stax amp you've heard. Period. Just like the Megatron is the best Stax amp I've heard. There's little need to regurgitate so many times that everyone does not want to know anything more about RKV. So it's no longer pro bono, if you think about it. It can be argued that you're a cost-centre [after my last post I just chanced upon your other thread.] instead of just 50 Euro... you're costing them potential business.
 
Anyways no offence man... just trying to lay it out for you and basically to let you know that chilling out a tad on RKV stuff may bring you closer to your goal... I remember this quote from Ghandi ..."In a gentle way, you can shake the world." I'm sharing that with you... just cause I think it makes sense here in this case.

 
Correction : " I'm a simple amateur. I work pro bono " --> read : " I work for free (and independently) in the audio forums (Head-Fi and HCFR) "
 
"You come yelling without any measurements but your ears and you demand to be taken seriously "
 
Not really. If you reread my posts you will see that I made a lot of measures; too many measures say some who think I spend more time measuring than listening... 

 

[JayM481]

I just discovered there's a "block member" function. The SNR has improved a great deal.

 

[RiStaR]

   
Correction : " I'm a simple amateur. I work pro bono " --> read : " I work for free (and independently) in the audio forums (Head-Fi and HCFR) "
 
"You come yelling without any measurements but your ears and you demand to be taken seriously "
 
Not really. If you reread my posts you will see that I made a lot of measures; too many measures say some who think I spend more time measuring than listening... 

 
I guess you don't get the point I was trying to make on pro bono. Anyways I've said my piece. Carry on doing what you want to do.
 
In terms of measurements... for amplifiers it's mainly to do with a scope... or something that lets you chart out freq response effectively. I don't think I've seen either of those from you. There's nothing wrong with not owning them (I can't afford to keep those handy), but I don't go round saying I've measured performance with my DMM also.
 
Life goes on 

 

 

[eric65]

If you are a lover of measures, here are a few: 

 
Objective response : in Volt and relative gain in dB / frequency, from amplifier RKV-II, combo RKV-Wee and RKV-Verto

Combo RKV-Wee (unmodified)
Output RKV = Input Wee = 0.20 Volt (at 1 kHz)
Output Wee = 0.20 Volt x 50 = 10 Volt (at 1 kHz) (with 1:50 Wee transformers)

My results are as follows: for 6 distinct frequencies (250 Hz 500 Hz 1 kHz; 2 kHz; 5 kHz; 10 kHz). Voltage measured, depending on the frequency, in input of the Wee (and therefore in output of the RKV) with the Wee transformers 1:50 connected, and with for load an electrostatic headphones Stax SR-009 145000 Ohm of impedance.

Signal sinus 250 Hz : 0.205 V (relative gain : 0 dB)
Signal sinus 500 Hz : 0.203 V (relative gain : 0 dB)
Signal sinus 1 kHz : 0.201 V (relative gain : 0 dB)
Signal sinus 2 kHz : 0.193 V (relative gain : - 0.3 dB) (to compare to the +2 dB of Kevin Gilmore graph)
Signal sinus 5 kHz : 0.160 V (relative gain : - 1.9 dB) (to compare to the -4 dB of Kevin Gilmore graph)
Signal sinus 10 kHz : 0.115 V (relative gain : - 4.8 dB) (to compare to the -17 dB of Kevin Gilmore graph)
http://gilmore.chem.northwestern.edu/rkv.jpg


Combo RKV-Verto
Output RKV = Input Verto = 1.69 Volt (at 1 kHz)
Output Verto = 1.69 Volt x 5.9 = 10 Volt (at 1 kHz) (with 1:5.9 Verto transformers)

Signal sinus 250 Hz : 1.692 V (relative gain : 0 dB)
Signal sinus 500 Hz : 1.681 V (relative gain : 0 dB)
Signal sinus 1 kHz : 1.666 V (relative gain : 0 dB)
Signal sinus 2 kHz : 1.614 V (relative gain : - 0.3 dB) (to compare to the +2 dB of Kevin Gilmore graph)
Signal sinus 5 kHz : 1.354 V (relative gain : - 1.8 dB) (to compare to the -4 dB of Kevin Gilmore graph)
Signal sinus 10 kHz : 0.965 V (relative gain : - 4.7 dB) (to compare to the -17 dB of Kevin Gilmore graph)
http://gilmore.chem.northwestern.edu/rkv.jpg


Combo RKV-Wee (modified) (1:50 Wee transformers disabled)
Output RKV = Input Wee = Output Wee = 10 Volt (at 1 kHz) (without 1:50 Wee transformers)

Signal sinus 250 Hz : 9.980 V (relative gain : 0 dB)
Signal sinus 500 Hz : 10.00 V (relative gain : 0 dB)
Signal sinus 1 kHz : 10.00 V (relative gain : 0 dB)
Signal sinus 2 kHz : 10.01 V (relative gain : 0dB) 
Signal sinus 5 kHz : 10.01 V (relative gain : 0 dB) 
Signal sinus 10 kHz : 10.21 V (relative gain : + 0.2 dB)
 
 
If the transformer (1:50 of the Wee box) is indeed seriously rolling off the mid highs with the RKV-II amp and SR-009 headphones, how we explain that we obtain the same results of measurement (at the microphone), under the same conditions, with the amplifiers for electrostatic headphones Stax : SRM-007t 2 and SRM-727 (a priori devoid of transformers)?

B: comparison of 009 headphones with amps RKV-WEE (unmodified) / SRM 727 / SRM 007t2 (NB: level benchmark standard for amplifiers: 73 dBA SPL at 1 kHz with the 009)
free-field measurements :

Dans l'ordre des colonnes : ampli RKV-Wee (non modifié) / ampli SRM 727 / ampli SRM 007t2 
(mesures réalisées il y a un peu plus d'un an lors du prêt du sonomètre de Pierre avec son SRM 007t2)

500 Hz : 73,2 dBA / 73,0 dBA / 73,3 dBA
1 KHz : 73,0 dBA / 73,0 dBA / 73,0 dBA
2 KHz : 75,0 dBA / 75,0 dBA / 75,5 dBA
5 KHz : 71,5 dBA / 67,7 dBA / 68,2 dBA
10 KHz : 76,5 dBA / 69,9 dBA / 71,0 dBA
12.5 KHz : 62,0 dBA / 56,0 dBA / 61,0 dBA

Conclusion : significant roll-of at 12.5 KHz (relative to the frequency control 1 KHz) with the three amplifiers RKV-WEE / SRM 727 / SRM 007t2 + Stax 009.
 
http://www.head-fi.org/t/677809/the-stax-thread-iii/2835#post_10762363
http://www.head-fi.org/t/677809/the-stax-thread-iii/2820#post_10759879
 
 
Life goes on, effectively 

 

 

[wink]

Quote:RiStaR

 Life goes on 

Anything you say will be just like water off a duck's back.
Block function is indicated here.

 

[Ali-Pacha]

Have learnt an english idiom today. Stax thread rules da worldZ.

Ali