Meridian Unplugged - Powered by MrTechGuy.co.uk Forums Discussion Meridian - Systems Surface Cabinet Temperature of G68 Cabinet

The surface cabinet temperature of my G68ADV is about 40 deg C (near to the AC power inlet vicinity) in standby mode when the ambient temperature is 30 deg C. My G68 seats on an open rack with 6" free space above it. Grateful if any G68 owner could inform me the equivalent surface cabinet temperature.

My story:
Two weeks ago, my G68 overheated to release some smoke and burning smell after a "pop" sound, a micro explosion. I sent it to my local Hong Kong dealer for service, who rectified the problem by replacing six capacitors in five days.


My concern:
Is 40 deg C surface cabinet temperature normal? My dealer may have just rectified the temporary problem, not the root cause of overheating. Although I know that my G68's surface cabinet temperature has been high since the day I have had it, the safety concern drives me to ask for a shared experience.


My observation:
My G68 took 4 to 6 hours to stabilise to 40 deg C after powering on. Operating my G68 at a about 30 deg C cabinet surface temperture resulted in an inferior sound quality - less details and blurr sound stage. This makes me feel safer.

Any shared experience will be highly appreciated. Thank you.


KC Lee

I had a similar experience re the pop and burning smell with my G68 a few years ago and sent the unit back to Meridian. I cannot remember exactly what the diagnosis was but it was something like a connection had fallen across the power rail creating a short and the power supply was subsequently replaced FOC (in those days)

Yours may be different but on the other hand?

regards

Rod

My G68 has had 2 new PSUs in its lifetime (the current one a few months ago). The first one blew with the requisite burning electronics smell.

The ambient temperature in my lounge is about 27degC today and the G68 is on a table in free air. The unit is barely warm to the touch in standby and definitely not 40degC.

MalcolmW,

I measured the temperature with an infra-red themometer. 40 deg C catches my attention. The internal temperature may be 60 deg C or above.

Grateful if you could inform me the surface cabinet temperature of your G68.

Thank you in advance.

KC Lee

I had the same issue. Bad PSU. $850 gone.

Room temperature is 25degC today. In standby, the top of the G68 at the rear is 32degC. As I am old fashioned, I used a mercury in glass thermometer!

Not the most accurate for this either mercury or infrared (unless calibrated for the surface), and quite warm your UK home Malcolm btw!

The G series PSU is a switched unit and does not get much warm (I had 08, 92 and 68), there may be other regulators and circuitry around that gets warm. With 25�C room temp my G units where, standby or not (M does not seem to like much the 'green thing') around 35�C, 38�C top. Your 'forty' sound normal to me.

The 861 use a quite similar PS (same?) but adds an extra board for filtering and regulation. It is too at around 35�C.

The 568 on the other hand bothers me more: linear PS ('old style' transformer, rectifier, etc) and many 7xxx regulator chips around plus the CPUs in a small place: it is 40-42 and even 45�C but the internals are not higher than 55�C as far is I have measured. This is why I have interest on the mysterious 'fan kit' available (?) for this units in the past.

Regards,

Josep

It's been the warmest day of the year here in the UK. Mind you, I have kilowatts of class A amps on. I agree that the 568 ran a lot hotter than the G68 does. Perhaps my new PSU is an improvement.

I will try to seek further information and will share with you the update later.

Thank you for all of you.

Here is my finding for sharing:

1. My G68's cabinet temperature is constantly 6 deg C hotter than ambient for both on and standby state. The hottest part is extra 2 deg C hotter, locating near to the AC power inlet.

2. According to my local dealer, G68's normal cabinet temperature is hotter than G61 and 861. Some gears of other brand can operate at 60 deg C cabinet temperature.

3. I think my G68's temperature is normal. The high temperature is a result of hot ambient in summer.

Since moving to southern China (1 hr from Hong Kong) I've been worried about leaving my G68 in standby as the case temperature gets high. I will see if I can measure it.

For reference I had a new PSU fitted just before I moved here in February.

There is close to 30W in heat being dissipated by the unit whether in standby or not. IIRC that my G98 was running a surface temperature of 40C in standby (my G68 was quite a bit cooler) and it went back to Meridian for thermal checks spending a few nights under a blanket and came back as 'normal operation'.