Author Topic: DL1608 destroying my Mac Mini(s)  (Read 25868 times)

RoadRanger

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Re: DL1608 destroying my Mac Mini(s)
« Reply #30 on: March 02, 2015, 10:25:45 PM »
Todays correct solution is a 1/8 stereo and either a split configuration to two of the TRS 1/4" plugs and link them for stereo or a single 1/8 stereo to 1/4" to the TRS 12-16 plug.
Also incorrect, a 1/8" stereo headphone jack has two unbalanced signals on it so the correct output is two TS plugs, not either one or two TRS plugs:
Input--OutL--OutR
T--------T
R---------------T
S--------S------S
« Last Edit: March 02, 2015, 10:32:56 PM by RoadRanger »

sam.spoons

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Re: DL1608 destroying my Mac Mini(s)
« Reply #31 on: March 02, 2015, 10:53:10 PM »
If you're in Euroville buy these http://www.orchid-electronics.co.uk/dual_isolator.htm, cheaper than Whirlwind and at least as good quality.

If they don't publish the specs, how do you know it's as good as the WW? For that kind of money, it would be difficult to produce truly high quality transformers. So I'm skeptical. The Whirlwind ISO 1 and ISO 2 uses their TRSP600L transformer which has max input of +20dBu at 20Hz before saturation and +26dBu before saturation from 100Hz on up. Those are pretty good specs. The only better transformers on the market are made by Jensen and Lundahl.

TBF I haven't tried the transformer boxes by Orchid Electronics but their active DI boxes punch way above their weight (respected reviews rate them an equal for Radial DIs at 4 x the price). Orchid is a small business who make exceptionally high quality (for the price) audio problem solvers. I have 4 of their DI boxes and the company I work as a freelance for has another 8, so the money/mouth interface is well represented.

ILC Saratoga

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Re: DL1608 destroying my Mac Mini(s)
« Reply #32 on: March 02, 2015, 10:59:09 PM »
Todays correct solution is a 1/8 stereo and either a split configuration to two of the TRS 1/4" plugs and link them for stereo or a single 1/8 stereo to 1/4" to the TRS 12-16 plug.
Also incorrect, a 1/8" stereo headphone jack has two unbalanced signals on it so the correct output is two TS plugs, not either one or two TRS plugs:
Input--OutL--OutR
T--------T
R---------------T
S--------S------S

Terminology is not my friend.   :)  But it is important.

Greg C.

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Re: DL1608 destroying my Mac Mini(s)
« Reply #33 on: March 02, 2015, 11:05:22 PM »
TBF I haven't tried the transformer boxes by Orchid Electronics but their active DI boxes punch way above their weight (respected reviews rate them an equal for Radial DIs at 4 x the price). Orchid is a small business who make exceptionally high quality (for the price) audio problem solvers. I have 4 of their DI boxes and the company I work as a freelance for has another 8, so the money/mouth interface is well represented.

FWIW, it's relatively cheap build a decent active DI. Transformers are a different animal. The inexpensive transformers work ok so long as you don't push low frequencies at higher levels into them. I wanted to make sure I could isolate a high output mix desk without distortion so I opted for the more expensive iso's ;)
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sam.spoons

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Re: DL1608 destroying my Mac Mini(s)
« Reply #34 on: March 02, 2015, 11:10:28 PM »
Configuration is Headphone jack (out) to XLR input channel 16.  Aux 2 to Mac Mini Input.
Very wrong, you should use the TRS "line input" jack on channel 16 that has no phantom on it - or an isolating DI - for any non-microphone input source. You could have just as easily fried a keyboard, acoustic guitar, submixer, or an amp DI output. Unfortunately this is a common problem amongst non-pro users :( . Expensive education for you but now you know :-\ .

And we have todays winner.  ;D Yes, a possible expensive education  :-\, aside from the amount of time spent.  Todays correct solution is a 1/8 stereo and either a split configuration to two of the TRS 1/4" plugs and link them for stereo or a single 1/8 stereo to 1/4" to the TRS 12-16 plug.  This avoids the circuit frying 48v phantom power.   This obviously falls under the WTH category and I'd love to accept total blame but I did have a professional help with the install of the mixer.  Thank you all very much for your assistance.  Now if I can just get the recording off the iPad without a lot of pain I would be good to go.

A stereo ⅛" jack to a TRS ¼" will not work, it won't fry your mac mini but it will sum your stereo output by summing the L&R signals in opposite polarity. Stick with TRS-mini to 2 x TS ¼" and you'll be ok.

A docked iPad will record stereo just fine to the MF recorder or pretty much any other recording app.

sam.spoons

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Re: DL1608 destroying my Mac Mini(s)
« Reply #35 on: March 02, 2015, 11:15:21 PM »
TBF I haven't tried the transformer boxes by Orchid Electronics but their active DI boxes punch way above their weight (respected reviews rate them an equal for Radial DIs at 4 x the price). Orchid is a small business who make exceptionally high quality (for the price) audio problem solvers. I have 4 of their DI boxes and the company I work as a freelance for has another 8, so the money/mouth interface is well represented.

FWIW, it's relatively cheap build a decent active DI. Transformers are a different animal. The inexpensive transformers work ok so long as you don't push low frequencies at higher levels into them. I wanted to make sure I could isolate a high output mix desk without distortion so I opted for the more expensive iso's ;)

Not going to argue with that Greg, knowing Orchid Electronics by reputation and from first hand experience I would expect all their products to be exceptional VFM but, as you say, good transformers are not cheap so I'll gladly withdraw my comments until I have tried one.  :)

Ampli

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Re: DL1608 destroying my Mac Mini(s)
« Reply #36 on: March 03, 2015, 06:05:30 AM »
Configuration is Headphone jack (out) to XLR input channel 16.  Aux 2 to Mac Mini Input.
Very wrong, you should use the TRS "line input" jack on channel 16 that has no phantom on it - or an isolating DI - for any non-microphone input source. You could have just as easily fried a keyboard, acoustic guitar, submixer, or an amp DI output. Unfortunately this is a common problem amongst non-pro users :( . Expensive education for you but now you know :-\ .

And we have todays winner.  ;D Yes, a possible expensive education  :-\, aside from the amount of time spent.  Todays correct solution is a 1/8 stereo and either a split configuration to two of the TRS 1/4" plugs and link them for stereo or a single 1/8 stereo to 1/4" to the TRS 12-16 plug.  This avoids the circuit frying 48v phantom power.   This obviously falls under the WTH category and I'd love to accept total blame but I did have a professional help with the install of the mixer.  Thank you all very much for your assistance.  Now if I can just get the recording off the iPad without a lot of pain I would be good to go.
Did use this solution before, the only thing it doesnt solve is the groundloop roblem if i use my laptop
With the power adapter from my laptob konnected there is hum, diconnect it and the hum dissapeared, using an di u can avoid this kind of problems

ILC Saratoga

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Re: DL1608 destroying my Mac Mini(s)
« Reply #37 on: March 14, 2015, 09:44:16 PM »
Did use this solution before, the only thing it doesnt solve is the groundloop roblem if i use my laptop
With the power adapter from my laptob konnected there is hum, diconnect it and the hum dissapeared, using an di u can avoid this kind of problems
[/quote]

Well, it seems that the cable have fixed the blowing out of the Mac Mini but now, I've got the Ground Loop noise??  I say this because it's an electronic thumping  whump whump whump, when connected to the Mackie DL 1608 but it goes away with head phones.  I've got one isolator but it's garbage, I'm open to suggestions, I know someone suggested one above, would this be adequate?  Oh this whole mess is going through a power conditioner.  Yes everthing is grounded.

sam.spoons

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Re: DL1608 destroying my Mac Mini(s)
« Reply #38 on: March 15, 2015, 11:21:28 AM »
If you're in the UK then the Orchid Electronics transformer isolator would be my choice, elsewhere ART do a suitable device.

nottooloud

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Re: DL1608 destroying my Mac Mini(s)
« Reply #39 on: March 15, 2015, 07:26:57 PM »
Yes everthing is grounded.

Try ground lifting the Mini's power supply.

Greg C.

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Re: DL1608 destroying my Mac Mini(s)
« Reply #40 on: March 15, 2015, 07:37:15 PM »
Yes everthing is grounded.

Try ground lifting the Mini's power supply.

No. If there's any ground lifting to be done, only lift signal grounds and never AC safety grounds. They're called safety grounds for a reason - they protect against electrocution and fire in the event of an internal fault.
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Greg C.

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Re: DL1608 destroying my Mac Mini(s)
« Reply #41 on: March 15, 2015, 07:38:30 PM »
It's also worth noting the Mac Mini has only a 2 prong power cord so there is no safety ground to lift.
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nottooloud

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Re: DL1608 destroying my Mac Mini(s)
« Reply #42 on: March 15, 2015, 07:51:34 PM »
It's also worth noting the Mac Mini has only a 2 prong power cord so there is no safety ground to lift.

Oh, yup, you're right. Might try skipping the power conditioner. Being as the DL1608 has known pin 1 grounding issues, he might try replacing the Mackie power supply with something better.

3rd prong is case-by-case arguable, however. I have both Lenovo laptops and Motion tablets where the same power supply is shipped with either a 2 prong or 3 prong cable, depending on I-don't-know-what. Many laptops have audio grounding issues that are easily solved by lifting the ground pin. At the very least, trying it can get you some information.

ILC Saratoga

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Re: DL1608 destroying my Mac Mini(s)
« Reply #43 on: March 15, 2015, 07:57:18 PM »
Correct they use a transformer on the MacMini.  It is basically a MacBook in a box. 

The problem has been solved by using a REALLY CHEAP 2 channel ground loop interrupter from MonoPrice.

 I had everything I needed laying around in the audio booth lovingly stashed into various boxes.  1/8 stereo to RCA, Ground Loop, RCA cable, RCA to 1/4" mono adapter.   :thu:  Now on to trying to figure out why the heck our hearing assistance is all static. Odds are something got unplugged.  Time to do some tracing and actually organization of the spaghetti pot of wires and cables.  Luckily they're easy to trace, all color coded, red and black... ;D

I'll be trying VoiceRecord to get the recordings off of the MacMini.  Currently we use Garage Band as it's very easy for our more 'mature' audio crew to figure out to record with.

I want to thank you all for your invaluable assistance.

gerenm63

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Re: DL1608 destroying my Mac Mini(s)
« Reply #44 on: March 16, 2015, 02:43:27 AM »
Correct they use a transformer on the MacMini.  It is basically a MacBook in a box. 

That depends on the vintage of Mac Mini. They've used internal power supplies for at least the past 5 or 6 years. In fact, I don't think they've used an external power supply on a Mac Mini since they switched to Intel (though I could be wrong about that last part).
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