Terrific event last Thursday in Atlanta. Thought I would share some photos…click on the photo for the google photos album…
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Great photos, @Lee, thank you for sharing 
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Thank you!
Lee, not a totally off-topic question, but I continue to see in dCS kit phots at Dealers where the Rossini APEX is sitting on top of the Clock on the same shelf – yet we’ve been told that to get the best SQ they need to be kept separate. Currently I have mine on separate shelves, but it’d be nice to free up space and combine them. I guess the logical solution is to try it combined and compare that sound to when they are separated. But since you are a happy and satisfied Rossini APEX / Clock guy I was hoping to get your thoughts. I know what the forum members suggest, but when I see Dealers doing this other way (like in the photos of the Evolution event) it makes me wonder.
Hi ksweiss,
I’m not Lee but I thought I would pitch in my 2c worth.
Clocks are quite sensitive to, among other things:
- EMI (which is generated by several components inside our DACs)
- Vibration (which is generated by things like transformers)
- Heat (which is generated by devices like transistors and regulators)
Hence the improvements we see in jitter performance when we place the clock crystals in a dedicated chassis. So the question of where to site the clock boils down to how much it might be exposed to the above factors.
We pay close attention to all the above when designing our products, so the amount of EMI emitted outside the chassis of one of our DACs for instance is minimal, as is the ingress of EMI from the outside. Although the chassis is an integral part of the heat dissipation regime (you will feel that the chassis becomes warm to the touch) the amount of heat transmitted to a stacked component (especially one stacked below) will be fairly minimal. Each of our chassis has feet designed to provide mechanical isolation in both directions. Etc.
So how much difference will stacking a DAC on top of the clock make to the above factors? You can actually measure the temperature before and after via Mosaic or the web interface, and even measure vibration using something as simple as an iPhone app. My guess is that placing the clock on a well isolated shelf on a decent equipment rack will have a greater positive effect than subsequently stacking a DAC on top of it will make to the detriment.
So I suspect that this is a case of marginal gains. But if you test, please report back on your findings!
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Andrew, thank you so much for your response, and maybe this was not a question pointed to Lee, more of a general inquiry. I do have a fairly good rack in place (Finite Element) and have the Rossini APEX and associated Clock on separate shelves. I think my question was probably rhetorical, but I was wondering more specifically why do we see them stacked in so may Dealer set-ups vs. as separates as we (the end-users) have been advised to do. I would think a Dealer would want the SQ to be at a maximum when demo’ing for a prospective buyer, so why display / demo them stacked? As an aside I also have my Rossini APEX on Magico Q-Pods (for better resonance management) and using these has made a wonderful improvement to the total sound quality and musicality of my system. I am considering adding these under the clock as well.
You’d have to ask Evolution, but I am guessing that there was another component on the shelf below the Rossini DAC and Clock before the event and someone simply missed separating them when they removed it. As I said, I would expect the difference on a good rack to be small, only the sort of thing you would really notice in your own system where you are already highly attuned to the sound quality.
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ksweiss,
In Evolution’s case, it has to do with other gear being shown.
My own Rossini Apex sits on Wilson Pedestals and I was surprised what a difference those made.