[DGCFAD]

  I talked with the guy at Questyle booth(SF meet), and he told me they were on the forth board with over 100 revisions to date. I asked him why would he tell me that? just makes me not want to buy the product. 
 
Every EE is going to make some revisions, but over 100 tells me there something very wrong with there design(imo).
 
I'll stick with Fiio, as there not just about making money, but genuinely seem to care about bring us wonderful SQ, at a very fair price point.
 
I also asked him about AAX, and AAX+ support, and he replied...whats that? In all fairness, two years ago I asked Fiio about AIFF support, and they replied, whats AIFF?
 
You'd think these new audio companies would know about all of the major audio formats.

I would like to start by saying that I apologize for whatever it is that I did to offend you, you seem to have expressed great deal of unwarranted anger towards my company, products and myself. It is certainly not my intent to offend anyone. It is my job however to translate what if fairly complex engineering into terms that are understandable by anyone, but to my knowledge, I have not done so without first being asked. I try not to talk down to people, usually if someone has a greater understanding of electronics engineering than I do (and there are quite a few of those), they already understand what I am talking about without prompting. That being said, there are two ways of designing audio equipment, "mass market" and "audiophile". In mass market products, you simply design a circuit, then use the cheapest available components, do some reliability testing and your done. If a mass market manufacturer wants to produce a "high-end" model, they will substitute a few of the components with popular named versions, and call it high-end. Audiophile products have always been half science, half art. A brilliant engineer without a good "ear" will produce an excellent designed, but mediocre sounding product. An audiophile design engineer painstakingly evaluates the sonic benefits and deficits of every resistor, capacitor and transistor of every manufacturer in every combination in their specific circuit, in order to produce the best possible sound, and if they are not completely satisfied, they change the circuit. Believe me, the first generation prototype of the QP1 would have made an excellent DAP for the money, but if Jason was satisfied with "good enough" Questyle would have never come into existence. It was the Quest for a better sound that drove Jason to begin experimenting with "current mode" operational amps for use in audio to begin with.
 
Not everyone can, or cares, or is willing to believe that the possibility exists to be able to, hear a difference between audio components. My best friend and her husband can't imagine spending more than $10 dollars for a pair of headphones, and choose their players based on UI and features vs price. Our product is not for these people, in fact, I would be willing to say that the majority of products at the Head-fi meet are for these people. If you fall into this catagory I recommend an iPod classic, it has the best UI ever achieved, and an excellent compression scheme for your 44.1 files.
 
As to AAX and AAX+ these are compression schemes designed for audio books and not music, I am sorry that I was not familiar with them, but they are a bit outside my purview, that being said, they are copy protected file formats, and the QP1 is not compatible with any copy protected file formats as this requires interface with external software to transfer the DRM licensing.

 

[x RELIC x]

And I don't think that Relic's post was specifically comparing Questyle's current mode amplification with the LC 'current feedback' opamp topology, either.  And altho I did notice the different posters involved, I didn't think that my general response would draw such a fine distinction.

Questyle's 'current mode' amplification, however patented, is still a subset of current controlled or 'transductance' gain circuitry, with Krell, Bakoon and Nelson Pass (F1) being other notable examples.  Maybe Questyle's brand of topology requires feedback for stability; who knows?  And Relic can ask Dr. Cavalli for clarification, OK? 

What I was more or less trying to express was that although they may not be the exact implementation I like the fact that both the LC and the QP1/R are taking a different approach to the amp design, and based on feedback on both devices the results seem to be similar. Very wide soundstage, excellent instrument separatation, great bass impact, etc, etc,.

 

[jacal01]

  Current amplification is unique and may be overkill but that's not the point as long as it works and sounds great.

 
Preaching to the choir. As an owner of 3 such current 'mode' amps, I happen to think that the advantages offered (e.g. clarity (minimum distortion, esp. TIMD), rapid response (transient decay), output impedence matching non-issue) are hardly overkill to a card carrying audiophile (the "card" in this case being a debit one

 ).
 
Questyle's specific topology may offer the advantage of low cost relative to the other current amps and/or small footprint required for the discrete components, allowing the development of a DAP product.
 

What I was more or less trying to express was that although they may not be the exact implementation I like the fact that both the LC and the QP1/R are taking a different approach to the amp design, and based on feedback on both devices the results seem to be similar. Very wide soundstage, excellent instrument separatation, great bass impact, etc, etc,.

 
My point is that they're two different animals, with the LC being the more conventional voltage driven gain amp.  Dr. Cavalli said via AxelCloris' linked reference that the LC is basically an offshoot of his earlier Liquid Glass, utilizing this same current buffer topology.  However, there may be multiple means to achieve similar results, so that in the end it is all about perceived SQ and musical engagement.  Just don't jump track on the topologies implemented just because the word 'current' is being bandied about.  I got caught on similar wishful thinking once or twice, myself.

 

[DGCFAD]

  And I don't think that Relic's post was specifically comparing Questyle's current mode amplification with the LC 'current feedback' opamp topology, either.  And altho I did notice the different posters involved, I didn't think that my general response would draw such a fine distinction.
 
Questyle's 'current mode' amplification, however patented, is still a subset of current controlled or 'transductance' gain circuitry, with Krell, Bakoon and Nelson Pass (F1) being other notable examples.  Maybe Questyle's brand of topology requires feedback for stability; who knows?  And Relic can ask Dr. Cavalli for clarification, OK? 

Amplifier design is a balancing act. The choice to forgo negative feedback, is a matter of trading higher component cost (the ratio of usable components as I remember it is 1 out of 100) and higher THD levels for reduced TIMD levels (which is not as easily measured, but is much more audible). The speed of Current mode amplification's extreme slew rate allows use to negative feedback without producing TIMD. i don't know why Bakoon chose to forgo negative feedback, as I see it as one of the primary advantages of Current mode amplification. Halcro, Krell and Pass Labs use Current mode transmission (IE: to get the signal from the pre-amp to the amplifier), and amplify in voltage mode, hence the choice to forgo negative feedback.

 

[jacal01]

Thanks for the distinction.  That clears up some of the confusion, at least in my mind.

 

[Hawaiiancerveza]

@DGCFAD , if the power has been upped to the same power of the QP1, does that mean the QP1R will also have similar battery life?

 

[Mr.Tom]

 
I would like to start by saying that I apologize for whatever it is that I did to offend you, you seem to have expressed great deal of unwarranted anger towards my company, products and myself. It is certainly not my intent to offend anyone. It is my job however to translate what if fairly complex engineering into terms that are understandable by anyone, but to my knowledge, I have not done so without first being asked. I try not to talk down to people, usually if someone has a greater understanding of electronics engineering than I do (and there are quite a few of those), they already understand what I am talking about without prompting. That being said, there are two ways of designing audio equipment, "mass market" and "audiophile". In mass market products, you simply design a circuit, then use the cheapest available components, do some reliability testing and your done. If a mass market manufacturer wants to produce a "high-end" model, they will substitute a few of the components with popular named versions, and call it high-end. Audiophile products have always been half science, half art. A brilliant engineer without a good "ear" will produce an excellent designed, but mediocre sounding product. An audiophile design engineer painstakingly evaluates the sonic benefits and deficits of every resistor, capacitor and transistor of every manufacturer in every combination in their specific circuit, in order to produce the best possible sound, and if they are not completely satisfied, they change the circuit. Believe me, the first generation prototype of the QP1 would have made an excellent DAP for the money, but if Jason was satisfied with "good enough" Questyle would have never come into existence. It was the Quest for a better sound that drove Jason to begin experimenting with "current mode" operational amps for use in audio to begin with.
 
Not everyone can, or cares, or is willing to believe that the possibility exists to be able to, hear a difference between audio components. My best friend and her husband can't imagine spending more than $10 dollars for a pair of headphones, and choose their players based on UI and features vs price. Our product is not for these people, in fact, I would be willing to say that the majority of products at the Head-fi meet are for these people. If you fall into this catagory I recommend an iPod classic, it has the best UI ever achieved, and an excellent compression scheme for your 44.1 files.
 
As to AAX and AAX+ these are compression schemes designed for audio books and not music, I am sorry that I was not familiar with them, but they are a bit outside my purview, that being said, they are copy protected file formats, and the QP1 is not compatible with any copy protected file formats as this requires interface with external software to transfer the DRM licensing.

Not angry at all, I've been into hiend audio since the beginning of it all. And you and your company seem to be throwing a boatload of money into marketing. Thick faceplates and heavy cassis don't make the sound, I wish you the best, and one day if I find your products to really sound better, for less money, I'll buy them. Good luck.

 

[moedawg140]

  Subscribed.. I also just learn a little about current amplification from the website.
 
I just place my order for the Q1PR...hope to get it by early Aug. I will compared it with my AK240. I have always being tempted to add a portable amp to the AK240 as I find it lacks the dynamic, punch of a dedicated amp at times. The Q1PR fills that gaps and still sound as detail as AK240. In fact I think its even more detail as the amplification section is really really good.It has a very good control of my UE18PRO and LCD X. As far as I can remember, the bass on Q1PR is so well control& full that it makes my AK240 sound weak. Don;t get me wrong, I like the AK240, smooth, relax and wide sound stage... but the Q1PR is also all that with more power and control.
 
The soundstage in Q1PR is also very big and spacious and 3D, I would say its at least on par with AK240 and could be more.
 
The above is based on Meet conditions. It may change when I have the actual product.
 
Hey Moe, nice to meet see you in person, I was actually looking for you to try the Omega IEM but I guess I was lost at the show. I am glad to hear you are driving the Q1PR with your HE1000. Its so awesome that this little DAP could drive full size headphone so well.

 
It was nice to finally meet you as well!  Always great to meet someone from the Shure SE846 thread.  I agree with your impressions - mirrors how I feel as well.
 
What's great is that for most people that won't drive hard-to-drive headphones very loud, there will be enough headroom for those who like to listen to their music loudly.  I remember seeing a friend at the SF meet showing me what volume number he liked to listen to my HE1000 + QP1R: 38 out of 60.  That means, a little bit more than half volume on high gain is enough to listen comfortably.  I like it louder, especially in meet/crowded areas, it sounds phenomenal and doesn't clip or lose any sound quality, even when the QP1/QP1R is playing at maximum volume (60 out of 60).
 
Hopefully next time I'll get in touch with you and you can try the Legend Omega to your heart's content. 

 

 

[yc1204]

It would be great if Questyle can design a dock like Astell & Kern or ZX2 for QP1/R, for desktop use purpose.

 

[jk47]

what's the story on not having a u.s. distributor?  anyone have any insight into this?  will there be a u.s. distributor?

 

[AxelCloris]

  what's the story on not having a u.s. distributor?  anyone have any insight into this?  will there be a u.s. distributor?

 
I could be mistaken but I believe headphoneaudiophile.com is an American distributor. I do know there are additional distributors lined up, but as they have not yet chosen to start taking orders for the QP1/R they will remain nameless.

 

[Hawaiiancerveza]

   
I could be mistaken but I believe headphoneaudiophile.com is an American distributor. I do know there are additional distributors lined up, but as they have not yet chosen to start taking orders for the QP1/R they will remain nameless.

Yeah Joe is the site owner.  He's taking preorders on his site.  
 
www.headphoneaudiophile.com

 

[DGCFAD]

  @DGCFAD , if the power has been upped to the same power of the QP1, does that mean the QP1R will also have similar battery life?

Yes, most likely, but I do not have published specs as yet. I have had no problem getting over 10 hrs at the shows on all the portables.

 

[DGCFAD]

  what's the story on not having a u.s. distributor?  anyone have any insight into this?  will there be a u.s. distributor?

We have a U.S. office rather than working through an independent distributor, so you will find our contact info on the "contact us" page rather than the "distributor" page of our web site. This is to the benefit of the consumer as the dealers deal directly with the company rather than through a 3rd party. It should be noted that distributors sell to dealers, not the consumer.
 

   
I could be mistaken but I believe headphoneaudiophile.com is an American distributor. I do know there are additional distributors lined up, but as they have not yet chosen to start taking orders for the QP1/R they will remain nameless.

 
headphoneaudiophile.com is a dealer not a distributor, and yes while we have other dealers, Joe is the only one I know of with an online presence. As to preorders, not all dealers are comfortable with taking money for new product that is not yet available. You can contact us at http://info_usa@questyleaudio.com for local dealer information or to make a preorder.

 

[jk47]

one head-fi'er who listened to the qp1r at the recent san francisco meet posted this:
 
 
Questyle QP1R DAP
 
This DAP offers something different to the rest of the portable player out there. It is a warm and slightly darker sound with full body and very good bass response. The soundstage and separation is very good although my first impression compare to my AK120ii it has less micro details and air on top that AK players seem to have. I didn’t try the line out to bypass the amp section and the designer told me line out is not configure for headphone listening. If I’m not mistaken battery life is about 10 hrs and the charging time is 2.5 hrs. Overall, it a really nice DAP and with bigger and full body sound that’s closer to desktop.
Gear: LCD X and occ copper cable, AK 120ii  
 
 
 
i'm curious about whether other people who've heard it would agree with this description, especially re the "warm and slightly dark" signature.