It’s been a while since I bought my QLS QA-550. Although I haven’t played much with it, but in overall, I like the quality of the player. Now, the new version has come, the QA-660.
One thing to be noted, this new player is much-much more expensive than its predecessor (well, you can find the retail price yourself). But spec wise, you will find a lot of improvement to. The major improvement is the support of multiple file format, like FLAC, APE, WavPack, and for sure, MP3. I don’t have to mention WAV, right? And the bit depth/sample rate also up to 24/192. This makes it a simple high resolution audio player. The screen also got updated with a massive 2.8″ AMOLED (you will know the reason why if you ever use QA-550). More gorgeous and expensive remote control also provided.
Enough for the introduction, let the pictures tell us more.
The front panel looks neat with black finish, and you can see some basic navigation buttons.
We have a complete output options, from Coaxial RCA, BNC, XLR AES/EBU, Optical, and IIS via RJ-45 type connector.
The USB is not for Flash Disk. So far, it’s reserved for future development.
The remote control and USB SD Card Reader. The remote looks expensive with a good grip (alhough not too heavy), while the SD Card Reader also performs very well in copying large files.
The basic structure inside the QLS QA-660. I would see and expect some performance upgrade by upgrading some components there.
The main transformer has three secondaries, 2x 17VAC and 1x 12VAC.
We can see Vishay capacitor to smooth out the DC signal there.
The output stage of the QLS QA-660. Some transformer also could have benefit from upgrading.
We have two master clock for 44.1 and 48 kHz. QLS claims 1PPM low jitter clock are used there.
One of them is 24.5760 MHz.
The other one is 22.5792 MHz.
The regulator is LT1086. Not just one, we can see few of regulators around, and all are LT1086 from Linear Technology. One of my favorite. Edit: There are 317, 337, 7805, and 7808 lying around. Sorry to miss this.
Most of the capacitors are Matsushita. Not a high grade capacitor, but I believe they could serve the purpose very well. This also could benefit for some upgrade.
Spec wise, this is quite promising. But then I have to find an adequate DAC to match this transport. At least, 24/192 must be supported as some of my collection now started to shift to 24/96 or 192 kHz. Thinking of Buffalo from Twisted Pear, but it seems Mr. Russ White is ‘on holiday forever’ so most of the time I always see ‘out-of-stock’ for his Buffalo kit and no emails ever replied (sorry!). Whether they make it too few, or the demand is too high. Only God knows 😉 The other option is to go if complete DAC, like Lavry or Lynx. Will see whatever meet the performance and the value.
Also one of the reader asks for detail shoot of the I2S chip. So here you go, Greg!
Tyo
November 5, 2012 00:06Om Jim, player digital seperti ini bisa nggak kolaborasi dengan DAC berbasiskan chip AD1865 atau TDA1541?
Auw Jimmy
November 5, 2012 21:43Bisa aja Om, kenapa tidak? 🙂
Tjipto Hendrawan
November 6, 2012 18:54Wah, nggak sabar nunggu review-nya 🙂
Tyo
November 6, 2012 22:54Design dan feature playernya menarik, oprekable banget ya. Banyak potensi upgradenya karena minim SMD. Kayaknya nggak nunggu lama, udah bakalan ganti jeroan nich.
Happy tweaking om jim…..
Auw Jimmy
November 7, 2012 17:22Sabar ya Om Tjipto, lagi nunggu DAC-nya dulu. Lagian preamp saya belum beres, amp juga lagi berantakan ga keurus he he he.
Mesti beberes dari debu2 dulu nih, sudah lebih dari setengah tahun ga denger audio secara serius.
Thanks.
Greg in Mississippi
December 30, 2012 03:20Jimmy,
Thanks for your posts on this player. It has me very interested. One question… does the manual provide any more information on the I2S connection than the website? Specifically, does QLS use a low-voltage digital signalling setup like the PS Audio I2S over HDMI (and also adopted by companies like SOtM, Wyred For Sound, and K&K Audio) or the Twisted Pear Audio Teleporters? Or does it just offer either a direct I2S feed (buffered or not)?
Your pictures show a chip of some sort in-line with the I2S output, but not enough detail to make out the chip’s ID.
Thanks… and keep us updated on the unit!
Greg in Mississippi
Auw Jimmy
December 30, 2012 20:35Hi Greg,
I would suggest you to contact the QLS HiFi directly. The email is available on their website.
The owner is quite friendly and surely he would provide more tech detail to you.
Thanks.
Greg in Mississippi
December 31, 2012 04:29I did and he did.
It does not use the LVDS setup. Pity. It does look like it is buffered… could you take and either post or email me a closeup picture of the chip upstream on the I2S output lines so I can confirm that?
Modifying it to use the LVDS setup actually should be pretty easy… One could pull that chip, wire in a Twisted Pear Transporter, and use the existing output connector since it already uses an ethernet connector.
I’m leaning towards getting one. Are you favorable enough on it to give it a ‘buy’ recommendation?
TIA!
Greg in Mississippi
Greg in Mississippi
December 31, 2012 04:33I should add that with an LVDS setup using the Twisted Pear Transporters, you of course need one at each end. But the benefit is that it allows transmission over a much longer distance than the recommended 50cm (which in my experience, is WAY too long for best sound… try 1-5cm!) with little degradation. 50′ is not out of the realm of possibility, depending a bit on what level of signal and clock integrity recovery your DAC has. One of the ESS-DACs run in normal ASRC mode would work well.
Greg in Mississippi
Auw Jimmy
December 31, 2012 19:34Hi Greg,
You got the picture.
Thanks.
Anonymous
December 31, 2012 23:41Thanks much, Jimmy.
That looks buffered, but I need to check… it may be re-clocked.
More later this week.
Again, thanks!
Greg in Mississippi
Greg Stewart
January 1, 2013 10:00Jimmy,
Again, thanks for the closeup picture.
The I2S output is definitely just buffered by the interface chip, U3. That chip is a 74HC125, Quad Buffer with 3-State Outputs. 3-state means that each of the four seperate buffers can be turned on and off by taking one pin high for each buffer. Those pins are 1, 4, 10, and 13. You can clearly see in your picture that those pins are tied to ground, so the buffers are all permanently on. All the chip is doing is provided a fairly good drive to the I2S lines and also isolating them (and any output cable loads) from the I2S generating chip.
But that takes me to the next level of investigation on this device… What is generating the I2S? I have two guesses… one is that the processor on the SD-card reader board produces it and then sends it to the chip roughly in the middle of the main board, the one that looks like it is labeled U1 in your picture labeled 8-Output. Then the U1 chip is likely an audio interface chip that is generating the SPDIF signals going to the other outputs… and the I2S is either coming directly from the SD-card reader board processor or taken from the audio interface chip. You can definitely see four lines coming from the SD-card reader board to U1, which could be the four I2S lines. But U1 is pretty far from the clocks.
Then I look at the cable connecting the SD-card reader board to the main board and I see a lot of lines which don’t seem to go anywhere. This makes me wonder if there is another processor or controller chip on the bottom of the main board that could be producing the I2S that goes to U3. But that doesn’t explain those four lines going to U1 from the SD-card reader board.
So I now ask for a few more closeup shots… one of each of the two main chips on the SD-card reader board, another of U1, and if you can, use your magic mirror to see if you can spot any major chips on the bottom of the main board (but don’t take it apart just for this!).
A few more thoughts about the unit, since you are planning to modify it.
First, on the surface, I like what QLS has done with the clocks. They are on their own grounding area to reduced ground-plane noise on the clock circuits. They also look to have at least separerate regulators for each clock, maybe even discrete regulators.
Second, if I am right and U1 is generating the SPDIF signal, then it is a good place to focus power supply upgrades at, especially if it just has a chip regulator. A discrete high-end regulator would be good here, Hynes, Belleson, or Dexa.
Third, if it were me (and it may be if I get one), I’d use the I2S output, connected by Twisted Pear Transporters, to a Twisted Pear or Acko DAC. Then I’d look at how to unpower the other outputs and everything not needed on the SPDIF side, as that processing is causing a lot of ground and power-supply noise. And even if you are using one of the SPDIF outputs, un-powering all of the ones you aren’t using (if that is pretty easy) would be helpful. I doubt that disabling the I2S buffer chip U3 would matter much, though.
Fourth, for power supply upgrades, I’d first look at the supplies to the SD-card reader board and the display boards and look at how to power them completely separately from the main digital audio signal processing board. Then I’d look at the supplies to the clocks and see how to power them with completely separate supplies.
Besides the power supply upgrades you’ve started getting parts for, what else are you looking at doing to it?
Again, thanks. And if you can do the other pictures above, thanks in advance!
And I hope my thoughts help!
Later!
Greg in Mississippi
P.S. You could posssibly reclock the I2S output using Potato Chip flip-flops as shown in GLT’s HiFiDUINO blog, but if that is not done just right before the DAC, it likely won’t help much.
P.P.S. If you only need a 2-channel DAC, the Buff-III SE is showing as available on the Twisted Pear site today!
Greg Stewart
January 1, 2013 10:30Jimmy,
One more question and one more thought… the question is what is the case material, steel or aluminum?
The thought… another quick and easy mod might be to see if you can remove power from the front-face control board while it’s playing & see if it continues to play… or at least power down the screen.
I had done an extensive mod to an old Philips CD player back in the 90’s and found that switching off the power to the screen and control circuits made a noticable difference. More recently, John Swenson has commented that unplugging the screen of a Squeezebox Touch makes a good difference in its sound quality.
Greg in Mississippi
Auw Jimmy
January 1, 2013 21:30Hi Gregg,
I think I would stop at this point to do this ‘reverse engineering’ process. I would expect someone who is interested to explore more could buy this great unit and start their own (or maybe post their own). It’s not too expensive and design wise, it’s quite friendly for some modification 🙂
I just feel not comfortable to share QLS design here in too detail manner (well, I have my own limit to share what I’ve explored and I do that in purpose). I think you can try to speak to Clark as he is a nice guy. Sorry for it.
I appreciate for your feedback and suggestion. Most of them are on my list previously. Also regarding the display, old CD Player from Denon or Marantz (forgot the exact one) also has the feature to turn off the display. Surely this helps in the past, but don’t know as at present time all section will use independent regulator. I doubt the noise would be shared between rails, though for the sake of ‘audiophool’, surely I have plan to disable the display 😉
Regarding Twister Pear. I have intention to buy that Buffalo before. Contacted Russ and the company few times, either on email or on the forum. You know the stock most of the time are not available for Buffalo kits. No answer or feedback from him or the company. I believe he must be damned busy and have a lot of business. So, I have given up with the Buffalo. Then, I would rather spend some more money to get either Lavry or Lynx HiLo DAC which I believe much more better than any DIY DAC solution (I’m not saying Buffalo or Twisted Pear) – and surely much more better support also as they are professional audio company. Maybe if I can convince myself to use media player solution (well, QLS could be a start) then I will look for Lavry, HiLo, Weiss, or maybe Antelope?
Thanks for coming back on this.
Greg Stewart
January 2, 2013 04:20Jimmy,
Thanks again for the info you’ve shared so far. I appreciate that. And I understand where you are coming from.
To be clear, I’m not trying to ‘reverse engineer’ the QA-660. I can’t… I definitely don’t have the knowledge or experience for that. Where I did find your review, comment, and photos helpful was in helping me decide if I want to buy one… and in what I might do to the unit from a modification perspective.
I currently run a cMP/cPlay music player with many tweaks and mods as my digital source (notice QLS’s mention of that setup in their original QA-660 writeup!). While I’m getting great sound, I’m thinking an even more purist solution might be an SD-card player.
I do like the QA-660’s fairly sophisticated processing and power supply designs. That it was designed with many separate regulators, separate grounding areas, and single-thread, minimal processing, are all strong points.
I also like that it handles more than 16bit/44.1KHz audio and more than just WAV files. If either the QA-350 or QA-550 did these two things, they’d be higher on my list.
And it looks like it will be possible to modify for better sound.
And While I’d prefer a PS Audio / Twisted Pear LVDS-style I2S, I can work with what’s there.
But what I’m most concerned about is the focus on SPDIF-type outputs. Clearly a large part of the engineering went into those outputs as evidenced by how much of the player is that circuitry. As I would be using the unit’s I2S output, that means that a significant part of the unit’s development and manufacturing costs are tied up in output formats I would never use and would want to disable (by disconnecting the power to them) to minimize RFI and EMI interference.
So I lose a bit of bang for the buck there.
If Chiaki & Bunpei’s SDTrans384 SD-card player was more easily available, I’d probably go for it. But as it isn’t, this looks to be the top choice available today.
Now just to decide if I want to go down this road.
Again, many thanks!
Greg in Mississippi
Auw Jimmy
January 3, 2013 14:34Hi Greg,
welcome, and thanks for your understanding. I believe I2S should be better than SPDIF. But at this present time, SPDIF is widely available and we have better choice with a lot of external DAC option. I would prefer to upgrade the output transformer, to have at least a better SPDIF.
Thanks.
Cowboy
January 5, 2013 06:11Hi Greg,
I may answer a few of your questions:
1. The case material is aluminum.
2. Please check the description from http://www.qlshifi.com/en/wzcapi/qa660.htm, and you can see a brief description for how the audio data flows.Drag down this page, there are 4 FAQs described a bit about the power supply design and PCB design. As for the SNR marked for QA660 is 140db that is pretty dark.
3. In the Chinese version website, it talks a bit about the cPlay+CMP combination, QA660 should be better than this combination.
John McDonald
February 13, 2013 10:26I have formatted a 128 GB SDSC card to FAT32. Then I downloaded a Rolling Stones album in a 176/24 WAV file. When I play it in the QLS QA-660 is sounds very bad – like a scratchy old LP. Any suggestions out there?
Auw Jimmy
February 13, 2013 11:00Hi John,
Have you upgraded it to latest firmware?
Secondly, what is your DAC? I have problem until now playing 192 kHz to my Xonar Essence One also. Haven’t picked another DAC, maybe later if I have some extra time to play.
Have you tried other 176/24?
Thanks.
John McDonald
February 14, 2013 03:18No, now aware of upgrading firmware. Is that for the QLS-660?
Actually the music is 176/24. I was wrong about it being 192Khz.
My Dac is a MyDac Micromega.
John McDonald
February 14, 2013 03:22Above, I meant that I am NOT aware of firmware for the QLS-660.
Auw Jimmy
February 14, 2013 11:35Hi John,
Well, just give it a try with a software update then. You know the website, right?
Thanks.
John McDonald
February 14, 2013 11:42Jimmy – no sir, I am new to this. I do not know how to update. Thank you very much for your great assistance.
Auw Jimmy
February 14, 2013 11:57Hi John,
Feel free to visit http://www.qlshifi.com/en/Download.htm
There are some instructions there.
PS: Btw, your XO caps is better than the old Auricap that I knew years ago.
Thanks.
John McDonald
February 14, 2013 23:14Jimmy – Wow, didn’t know you used our caps; thank you! Yes, the XO caps are definitely better. Please spread the word and thank you.
Thank you for the instructions link!!!
Auw Jimmy
February 14, 2013 23:32Hi John,
The distributor here in Indonesia is my good friend. One of my favorite caps, especially in power supply. Superb caps.
Thanks.
John McDonald
February 16, 2013 02:40Jimmy, from the link you provided I downloaded the V3.2 document. However, I could not read it due to the unrecognizable file type.Can you send me a PDF to [email protected]? Many thanks! John
Auw Jimmy
February 16, 2013 21:00Hi John,
I believe the readme file is just a basic text file. Quite confused why you couldnt open it.
Thanks.
John McDonald
February 16, 2013 22:22Jimmy – the file is a .rar which I cannot open.
Auw Jimmy
February 16, 2013 22:48Hi John,
Please download WinRAR.
Thanks.
gunawan
March 15, 2013 18:12Pak Jimmy, apa pernah bandingkan dengan Marantz NA7004?, kalau saya sudah ada DAC Sonic Frontier SFD1 lebih baik pakai yg mana ya pak?, atau ada saran lain? misalkan DAC yg bisa play Wav sekalian buat replace DAC lama saya, thank’s
Auw Jimmy
March 15, 2013 18:21Hi Pak Gunawan,
Maaf belum pernah bandingkan (sebenarnya saya juga belum sempat coba terlalu lama, masih dianggurin juga sejauh ini).
Kalo sudah ada DAC-nya, silakan dicoba dulu saja Pak.
DAC tidak ada yang bisa play WAV.
Thanks.
gunawan
March 20, 2013 08:58ok, thank’s pak Jimmy
Auw Jimmy
March 20, 2013 16:05Sama2 Pak Gunawan.
Thanks.
Unclesam
November 5, 2013 16:20Hi!
I want to replace IEC Input Connectors (for example on Furutech FI-03) and FUSE.
Which brands, types, models and You prefer to advise.Can I put a fuse with a higher than 0.5 A?
Thank You very much.
Auw Jimmy
November 5, 2013 22:05Hi Unclesam,
Furutech could be a good start. I prefer to use the same rating for fuse.
Thanks.
Unclesam
November 6, 2013 15:22Hi, Jimmy!
Thank You very much for Your answer.
What do You think about CREATE AUDIO Luxury Nano Fuse & CREATE AUDIO DB-14F IEC Input Connectors ?
Thanks.
Auw Jimmy
November 6, 2013 16:58Hi Unclesam,
You are free to experiment…
Thanks.
Unclesam
November 6, 2013 17:57Thank You very much for Your answer.
anno
June 11, 2015 00:08masih dipake ga nih om? lagi nyari sekenan nya nih klo ada
Auw Jimmy
June 12, 2015 18:59Uda dijual, Om…
Thanks.