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Old 19th September 2012, 11:32 AM   #4041
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I'm finally building the My-Ref c kit I ordered a few years ago and wondered whether anyone knew if the amplifier has problems with a high Capacitive load from the speaker?

The reason I ask is because I've been reading the articles on speaker cables on Rod Elliot's site, and am considering constructing a braided Cat 5 speaker cable in order to reduce the inductance and resistance. However the downside is high capacitence, which is fine if the My-Ref C can handle this, but is a no-go if it can't.

Can anyone shed any light onto this?

Thanks
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Old 19th September 2012, 02:31 PM   #4042
bcmbob is offline bcmbob  United States
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I have had excellent results with a recent build of this DIY recipe combined with the MyRef - Fremem Edition. Should be the same with V1.2 and V1.3.

The photo is what I used for almost a year with no amp stability problems at all.
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File Type: jpg Braid.JPG (173.5 KB, 513 views)
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Old 19th September 2012, 03:04 PM   #4043
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Thanks Bob

That's exactly the same "recipe" I've been looking at
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Old 19th September 2012, 03:30 PM   #4044
bcmbob is offline bcmbob  United States
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You'r welcome. A little tip - don't be stingy with the initial length. I started with 14' cuts and ended up with a cable ~ 10' after the third braid. There is a dramatic difference between using a tight and a loose braid. Starting in the middle of each course and braiding to the ends is a lifesaver. Cat6 reportedly has a little higher grade copper than Cat5.

My Impression of these is an improvement in both stage reality and clarity/separation. Bass is controlled and abundant. I have never owned any high dollar boutique cables but I have heard a $600 set at a friends house - with the FE amps. I'm keeping my cash in my pocket

Good Luck!
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Last edited by bcmbob; 19th September 2012 at 03:38 PM.
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Old 19th September 2012, 04:03 PM   #4045
troystg is offline troystg  United States
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cat5 and cat6 copper is the same. Difference is twist and internal divider for space separation.

I use Kimber 4TC which cost more than this amp and the cat5/6 is close.
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Old 19th September 2012, 04:06 PM   #4046
bcmbob is offline bcmbob  United States
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That's good to hear Troy, Thanks
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Old 19th September 2012, 06:19 PM   #4047
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Thanks guys, much appreciated.
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Old 20th September 2012, 01:35 AM   #4048
soongsc is offline soongsc  Taiwan
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I have used Aplha Core cables with good results.
If you plan to braid your own cables, the best results seems to be when the conductors intersect in a perpendicular way, Speakerbuilder published this a long time ago. Best to use twice the length of what you actually need to begin with.
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Old 20th September 2012, 07:17 AM   #4049
AndrewT is offline AndrewT  Scotland
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braiding increases inductance, not lowers it.

Close coupled pair is the closest for least inductance and maximum capacitance, for a pair.
Star quad is higher in capacitance and that probably means even lower inductance, but I'm not sure since I have not seen a reference.

The more cores in the bundle, the higher the capacitance , if the flow and return cores are still adjacent.
If all the flows and all the returns were each bundled and then the two sets were close coupled, the capacitance would fall and the inductance would rise.

Braiding has a similar effect, it introduces air spaces between the flow and return cores. That removes the "close coupled" geometry and results in lower capacitance.
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Old 8th October 2012, 08:04 AM   #4050
bismuth is offline bismuth  France
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Default Square wave response question

Hi,
I've just finished to solder two monoblocks (Rev C PCB rev1.3 I've bought almost two years ago from linuxguru...).
Before plugin to the speakers I've done some basic measurements. DC Offset at output looks ok around 2mV and 5mV, but square wave response is strange above 3Khz, it is very "damped" compared to what I'm used to see on a classic gainclone. Here are two pics of a 5Khz square wave response, one from a MyRef monoblock and one from a LM3875 minimalist GC,.
Is that the normal MyRefRevC behavior ?
Is it safe to plug the "real" speakers ?

Thank you for your help,
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File Type: jpg MyRef_5000Hz.JPG (117.0 KB, 330 views)
File Type: jpg LM3875_5000Hz.JPG (131.2 KB, 311 views)
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