Christopher

Hi Alex, Wow. Your electrician must love you! Very impressive overview of your isolation and power set-up. I’d like to say thank you for taking the time to walk me through your tests and observations in such a comprehensive and organized way. I feel bad asking questions that might have been a chore to respond to. Sorry if that was the case. Totally agree with you on power supplies and why isolation can be helpful. Installing a dedicated line was one of my best investments. In my case, isolation after the wall outlet wasn't crazy expensive, and it too pays dividends. While I’m not prepared to slow down to FW400, I just ordered a Corning 3.5M Tbolt optical cable for electrical isolation (glad they come in more reasonable lengths these days and not just long runs over 5M or 10M). It should arrive this weekend. I’ll see if there are any improvements or audible differences. I’d like to think i already have pretty good USB isolation from Mac Mini to DAC. Even if electrical noise is leaking into my computer via the generic Tbolt cable (from OWC), hopefully it doesn't make it to my DAC. Well, i know enough to know that there’s a lot i don’t know...so let's see how it sounds. Cheers, Chris

Hi Alex, Understood and agreed on the fan noise issue. I'd like to take this opportunity to say hi and good to meet you here at CA. And, wow, you have an incredible system/room! I haven't posted in long time as we moved (locally, less than 20 blocks) and then embarked on a gut reno (not easy or fast in nyc). Indeed, most external drives with fans are noisy...and too loud for me. For many years in the past, i used Glyph external drives and, while reliable, they were super noisy (love Glyph as a company, but they were just too loud for me at home). I tried to remedy the noise issue in many ways...finally arrived at a near-silent enclosure linked in my sig. Sorry, the post/link is old and my build-pics are no longer available. I still use the "silent" enclosure with my new drives. Noise is no longer an issue thanks to the sound dampening enclosure. As you pointed out, fanless would certainly be more quiet. I wonder if fanless might impact drive longevity? Have no experience or testing there. I see you prefer FW400 vs some other connections. I haven't tested this personally. When you compared FW400 vs other connections (FW800 or other), did you isolate power for each HD in all of the tests? Just wondering if there are other factors that may have resulted in FW400 being your preference? For example, i noticed an improvement after building/assembling the silent enclosure with it's own power conditioner (I'm using PS Audio and Furman stuff). Isolating the power for DC/wall wart power adapters away from DAC and Pre seems to make a difference for me and others have shared thoughts on this in the past. Personally, i try to isolate each piece of equipment (as you did, i had the the contractor install a dedicated line with a separate panel for my system). Concept/question: does noise travel forward through the FW/USB/Tbolt cable from the external HD into the computer and then into the audio chain? Or, does noise travel backwards (in reverse) from the HD's PS into the system? Any personal testing or experience with this? Respectfully, this is not a trick question or otherwise motivated to stir something up. Sincerely interested in your experience and point of view. Best regards, Chris

I have a late 2012 Mac Mini. There is only one Tbolt port and a FW800 port. Having faced similar questions and considerations, here are some personal observations and experiences. My DAC is connected via USB and i wanted to keep external storage separate from the USB hub. Initially (before Tbolt drives were as common as they are today), i went with an external FW800 drive. I had a very reliable 3TB external HD from OWC via FW800. Link to today's version: Macsales.com - OWC Mercury Elite Pro USB 3.0/2.0, FireWire 800/400, eSATA External Hard Drives This unit was great unit i exceeded storage. It was fast enough, very quiet and reliable. Highly recommended if you only need FW800 and not Tbolt. I didn't use raid or partition the drive. Backups were manual and i was concerned about a possible drive failure between backups. FWIW, the drives never failed over the course of about 2 years. After i maxed the storage capability, I considered NAS or another approach. I decided to go with a 6TB Tbolt external unit. Link: OWC 6.0TB Mercury Elite Pro Dual USB 3.0 &... in stock at OWC This unit is not very expensive and can be daisy chained via Tbolt (from one HD to another; the Mac only has one Tbolt port). It has a small footprint, is relatively quiet and does not require software for raid settings (raid can be set by a turn key on the back of the HD). I'm running raid 0 for speed and max storage capability. Instead of mirroring drives, i prefer a backup on an alternate dup external HD that is only connected at the time of backup. Caution: in the event of drive failure, i only have data as of my last backup. Tbold makes this fast and easy. Hope this helps, best regards, Chris

Sounds like a great idea. Would welcome meeting local members and perhaps hosting too! I'm in midtown. Cheers, Chris

Hi Chris, Great review. Really appreciate your layout of scenarios. What a terrific guide! I use scenarios 1 & 3 with my HD580 headphones at my desk (they are older, but reliably enjoyable). Love the versatility, value and performance of this product. Sending my best from NYC and thank you as always, Chris

Wish we knew the great news when we met you in NYC. Kate and I send our best wishes and congratulations! All our best, Chris

Hi Chris,<br /> <br /> I plan to stop by Stereo Exchange this weekend.<br /> <br /> Looking forward to meeting you and other CA members in NYC!<br /> <br /> Best regards,<br /> Chris<br />

Hi dmgbat, Sorry for the delay in getting back to you. I made my speaker cable elevators with anti-static foam and porcelain isolators. The foam comes in sheets conveniently perforated into 4” x 4" cubes with peel n’ stick adhesive on one side. I put two cubes together by mating the adhesive sides together. This created a rectangular 4” X 8” brick. Then, I carved the foam brick into a pyramid shape with a serrated bread knife. I left enough foam material on top so the U-shaped porcelain isolator can slide on snugly and firmly (tongue and groove...there is no need for glue). I use 3” round self-adhesive non-slip rubber pads under the elevators so they don’t slide around on the floor. My Nordost cables sit vertically perched on top of the final elevator in the porcelain groove. Since the foam is a pinkish color, my wife refers to these guys as Pink Elephant Feet. Here are links to the materials: http://www.uline.com/BL_8005/Anti-Static-Plank-Foam http://www.amazon.com/Fi-Shock-MP-4-Heavy-Duty-Porcelain-Insulator/dp/B0046ECXRO/ref=sr_1_18?ie=UTF8&qid=1330179285&sr=8-18 http://www.amazon.com/Non-Slip-Rubber-Almost-Anything-Place/dp/B001ECSE2O/ref=sr_1_16?ie=UTF8&qid=1330179753&sr=8-16 I had to buy a box of the foam from the supplier and had ample left over. I use the extra foam as an aid in cable management. It’s easy to cut and you can carve channels into the foam so that interconnects and power cables do not overlap or touch each other. Hope this helps, Chris

I’ll move forward with the 15” 2.5GHz quad-core Intel Core i7 with SSD. <br /> <br /> Looking forward to comparing its performance vs my iMac.<br /> <br /> Best regards,<br /> Chris<br /> <br />

I decided to make a quick trip to my local Apple store. Here’s the deal.<br /> <br /> ***The 2011 15” Macbook Pro USB Device Tree looks like this***<br /> <br /> USB High-Speed Bus<br /> Face Time HD Camera (Built-In)<br /> Hub<br /> BRCM2070 Hub<br /> Bluetooth USB Host Controller<br /> Apple Internet Keyboard / Trackpad<br /> <br /> USB High-Speed Bus<br /> Hub<br /> IR Receiver<br /> <br /> ***The 2011 17” Macbook Pro USB Device Tree looks like this***<br /> <br /> USB High-Speed Bus<br /> Face Time HD Camera (Built-In)<br /> Hub<br /> Apple Internet Keyboard / Trackpad<br /> BRCM2070 Hub <br /> Bluetooth USB Host Controller<br /> <br /> USB High-Speed Bus<br /> Hub<br /> IR Receiver<br /> <br /> I’m guessing this means that there is not much of a difference between the 15” and 17” in terms of USB Hub architecture.<br /> <br /> I hope one of the USB ports will result in the DAC showing up in the second Hub with less stuff and only the IR Receiver to deal with.<br /> <br /> I’m interested to know if there is a way to disable the IR Receiver so the DAC will have a completely free hub.<br /> <br /> Does anyone have experience with Candelair as a solution to disable IR and remove it from the USB Hub?<br /> http://www.iospirit.com/labs/candelair/<br /> <br /> Should I even be concerned about this?<br /> <br /> Thank you,<br /> Chris<br />

I’m planning to get the new Macbook Pro (late 2011 model). The 15” has 2 USB ports...the 17” has 3 USB ports.<br /> <br /> I prefer the 15” 2.5GHz quad-core Intel Core i7 vs the 17” model because of the slightly smaller footprint. However, I’d like to make sure there will be a free USB Bus without Mouse, Keyboard, IR Receiver or Bluetooth for my DAC.<br /> <br /> Does anyone know if either the 15” or 17” have a free USB Bus available (I will not connect any other USB devices except for the DAC)? <br /> <br /> Additionally, are there any other considerations that would likely make one a better dedicated music server than the other?<br /> <br /> Thank you,<br /> Chris<br />

I really like what you succinctly and eloquently stated... Quote #1 “...I totally disagree with only the "top contributors" being allowed to say if a post is good or not. One of the purposes for suggesting such a thumbs up scheme was so that newbies could see what information is good or potentially irrelevant. If only top contributors have that power then you're just creating a clique where some posters are more important than others.” Personal comment... Allow me to add that some regular readers, like me (a member for some time with relatively low post count), aren’t able to post a lot. In my case, mostly due to travel and other considerations. Restricting ratings to people who are only able to make regular and frequent postings could be a slippery slope with consequences, i.e., the click/club you mentioned. Quote #2... “One forum I visit has the ability for users to click "Thanks for this post". I guess my motivation in my suggestion was that it's nice if someone shows there appreciation when you're spent several minutes writing out a reply. People generally don't write a post to say thanks sadly.” Personal comment... Agreed again. Unfortunately, and apologetically, I often fall in the category of “...generally don't write a post to say thanks...” when I read something that I consider to be value-added and educational. Regretfully, this happens too often. I would really like a way to say thank you quickly without having to login. Even if login is required, I would like the opportunity to express my appreciation for the knowledge, time, effort, and thoughtfulness associated with some posts without having to create a new post. The concept of pressing a button to respond with my personal ‘thank you’ would be great. Note to Chris C... If it were easy for me to press a button from my computer or mobile device to say “Value Added” or “Thank you”, I would, personally, like this feature a lot. Please note my sincere thanks and appreciation for all the contributions here at CA. With best regards, Chris

Personal opinion on balanced... For me, “balanced” means fully balanced internal circuitry. In other words, not just XLR connections that are a connection "accommodation” without fully balanced internal circuitry inside the component. I think Bob just touched on this. In my experience, fully balanced internal circuitry can have a solid advantage in noise rejection. It’s possible that balanced circuitry sounds better because it avoids extra amplifier stages and/or transformers that require front-end unbalancing and back-end rebalancing (and I trust there’s a lot more to it). This being said, I have listened to...and experienced first hand...the downside of XLR connections with an amp that *did not have* fully balanced internal circuitry. It just didn’t sound right with XLR cables. What was the amp?...Rotel RB-1080. A few years ago, my system sounded less dynamic and less resolving with XLR connections vs single ended connections with the Rotel RB-1080. After I changed cables from XLR to single ended, the exact same amp sounded better. Today, my system is balanced with Ayre gear and I would probably not go back to RCA. But, I think results can vary based on equipment and the quality of cables. Balanced may not *always* yield improvement. On a side note, I still love my Rotel RB-1080 amp. Today, I use it with outdoor speakers and it really shines. And yes, I use RCAs with the RB-1080. Barrows and Bob, please let me know if you have any corrections or clarifications re my logic on this. Best regards Chris

I hear you about noisy. Unfortunately, I have to report that my hard drive enclosure was a one-time-event for me. I’m very happy with the results; just too much work for me to duplicate. Hopefully, the steps are clear enough for you (or your designee) to make an equal or better box! I’m happy to weigh-in if you have questions (just keep in mind, I’m not an expert). Btw, I’m in midtown Manhattan. PM me if you are in town. Cheers, Chris

This is a cool and interesting discussion. I’ll try and provide some general feedback that captures my overall impressions of the QB-9. I can’t comment on the Calyx unit, but I’m interested in hearing it! My comments are simply an effort to share my particular point-of-view regarding the QB-9. Before I proceed, allow me to share a few important notes/caveats in advance... (1) I’m not using a stock power cable...I find the LessLoss DFPC makes a material difference (2) I find placement/dampening/mass-loading makes a material difference (3) I’m using AQVOX USB Power Supply and Acromag USB Isolator upstream before the QB-9...in my environment, I find additional USB isolation makes a material difference (this is controversial...some suggest isolators like mine are not good) This being said, here’s my quick-take on the QB-9... * When sounding best, drums, standing bass and acoustic guitar are believable and life-like (my highest compliment). * Vocals are usually very good. When best, vocals are believable and life-like. Singers can be pinned in center (usually studio recordings) and also walk across the stage (mostly live recordings). * Overall, bass is excellent...fast, not overly pronounced or muddy...and when it’s supposed to be there, it’s tactile (feel it in your chest stuff). * Strings are superb. Acoustic guitar and standing bass sound real...especially when it comes to hearing stuff like fingers moving across fretboards. Passages can float in air with separation between notes. * Snare drums snap and snarl...I can hear sympathetic vibrations on low passages. * Kick drums have kick. * Cymbals have the right sizzle and decay. In this context, decay means the fade from just being hit...to nothing...and then the next strike. Not too bright, dull, muted or muddy...it’s just right. * Piano can vary a lot. With some recordings, I feel like I’m hovering over the shoulder of the player with almost no stage. Other times, I feel like the piano has a precise place on stage. For me, I expect a DAC to reveal stuff like this. * Horns can be cool or a hot without sounding metallic. For me, this is impressive. In this context, hot means blowing so hard that spit and heat from one’s breath can alter the sound of an instrument...cool suggests the absence of, or less of, this effect. My subjective ranking in qualitative terms... With a purely subjective scale from 1 to 10 (ten being the highest), I’d rate the QB-9 a solid 8. There are times when everything seems just right and I’m tempted to be generous with a ranking of 9. But I know/feel/believe things can be improved. I also have a Benchmark DAC1 Pre. On the same scale, I would rate the comparative performance a relative 6. This is not meant to be harsh or critical regarding the Benchmark, it’s just my subjective take on a relative basis (not in absolute terms). Personally, I think Jacques_racine is calling it as he hears it...and that’s cool with me. I respect his opinion. Just wanted to share that the QB-9, in my system, is capable of stuff that resembles certain feedback from Jacques_racine’s initial post; namely, “generous, spooky-real, lively, fast, reveals the acoustics of the venue, amazing PRAT” (not my words, and not exactly my experience, just a quote that’s similar to my overall experience). Best regards, Chris