DirectStream Junior runing hot

Audio Components DACs
21

If you do, check the temperature of the pre now and then.

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Given how hot he DSJ runs, I personally would be uncomfortable placing anything on top of it.

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@tedsmith & @dancingsea thank you. I will rearrange the hifi rack to have the dsj on itself.

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That’s a good idea, and really nice looking rack! Some DSJ owners have had issues where the top black panel warps from the heat. The only thing I’d consider putting above it is a fan…

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@dancingsea thank you, just don’t ask me for a photo of the back, it’s a mess. Moved things around, the Dsj is now on the top, doesn’t look as nice but should have less heat. There is nothing on top of back halve the stellar. Hope it won’t get too hot for it or I will have to move the other stuffs off it.

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Tried a few fan before, the closest I got is laptop stand coolers, it is now sitting on top of the marantz sr7012 and auto turns on when I am watching movies. I found most fans are too noisy for it liking.

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Sold my DSJ, but it ran pretty warm. I used one of these T8 coolers. Not required - but the cooler is great for enclosed cabinets. I have five of them and a model S6 in my setup.

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@netspecht-2 Thank you, nice looking coolers. I will look for them for Australia. Funny how it has a picture of a Marantz avr with the Aircom. I think this one will suit me for the bottom 3 racks and https://www.acinfinity.com/component-fan-systems/aircom-s9-receiver-and-av-component-cooling-fan-system-top-exhaust-17/ for the DSJ. Will need to measure up for the rack clearance.

Another option is to go back to my previous setup DSJ on the bottom AirCom S8 in the middle and the Stellar on top.

I am currently using a cheapo similar to this one https://www.ebay.com.au/itm/Laptop-Cooling-Fan-Notebook-Cooler-Stand-USB-Fan-Pad-with-USB-Hub-AU-Stock/252679936671?hash=item3ad4e5da9f:g:J6IAAOSwq9hdcgWs&frcectupt=true . It has a USB power connector which i connect to my media player -> power on to cool the Marantz and Power Amp during movies.

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28

Ted, what do such ratings mean in practical operation (as 5000 hours for a constantly switched on unit roughly means 200 days troublefree Operation in case the cap has 105C)?

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The smart fans are nice since you can adjust speed. On max fan speed you can definitely hear them. I just installed an 12” wide S6 today for my new Headamp GSX-mini headphone amp. It doesn’t have the temp readouts, but the fan kicked on and off when the amp heats up. Pretty quiet too, AC Infinity does ship international, but you have to deal with that VAT stuff. They are only about an hour and a half from me in Southern California.

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30

In general each lowering the temperature of a electrolytic capacitor by 10 degrees C will double the expected lifetime. So caps rated at 125C should last about 4 times as long as a caps rating at 105C (with the same hour rating.)
At the end of the lifetime of the cap it shouldn’t have deviated more than a certain amount from it’s initial specs:

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I use 125C’s if they are near a heat source. The hottest part of the Jr are the heat sinks on the top level power regulators, but in general the insides are more like 50C, which translates to approx. 128 x 2000 or 128 x 5000 hours which is decades. And also the unit will work fine with caps that are further from their specs than those listed under the endurance section.

When the bridge isn’t being actively used it uses less current and the bridge is by far the biggest user of current in the box, hence the biggest source of power supply heat.

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31

Thanks Ted, that makes it clear.

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Great chart Ted. Thanks.

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Hello Ted
Thanks for providing much information of the Bridge. Unfortunately, the high temperature is still a concern in my listening environment. A question: Is it possible to disconnect Bridge from the mainboard of DSJ? Thanks!

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Yes, the bridge is a separate module. If you take it out and later want to put it back, be very careful of the pins and align them carefully when you plug it back in.

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35

Hi Ted, I successfully removed the bridge from DSJ today. The removal needs to be handlled carefully since your product is so robustly assembled. I realized DSJ is not just a “junior” :muscle:.
After the bridge removed, the upper glass is cooler now. Since I only use USB, removing it may be positive to me as “simple is better” :grinning:. Thanks again!

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