Hmmm…why bother!

MajorFubar

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I had cause to break open my PM66KI this last weekend because the right channel had packed in. When I popped the lid I was quite impressed by the neat and orderly construction and I noticed Marantz had gone to the trouble of using high quality components in key areas, presumably to help with SQ. However when I found out what was wrong with it, it did leave me wondering whether their efforts elsewhere were partly wasted.

The volume control is connected to the pre-amp board via nothing more high-brow than a 6" piece of ribbon cable, like you find in desktop computers. Removing it, cleaning all the contacts and refitting it restored my missing channel.

So irrespective of your opinion of specialist interconnects, speaker cables and 'audiophile quality' electronic components, it's food-for-thought that after all your efforts, internal key parts of your HiFi's audio-chain are linked together with nothing more than thin ribbon cables.
 

The_Lhc

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If it's an electronic volume control it's not carrying any signal (I'm not even sure it is if it's a pot to be honest), so the quality of the cable doesn't matter. What I found more amusing was during the KEF demo at the Bristol show, they handed round a driver from the T-series which has some of the thinnest wires going to the voice coil you've ever seen.
 

Craig M.

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it's my opinion that the internet will allow people to find out the truth about lots of things, and those who have maintained a certain position will look very silly or corrupt. bring it on.
 

Andrew Everard

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Craig M. said:
it's my opinion that the internet will allow people to find out the truth about lots of things, and those who have maintained a certain position will look very silly or corrupt. bring it on.
Aliens, secret world government, what really happened in the bunker in Berlin, who killed Marilyn – all pretty downbeat stuff...

And totally misses the point that the OP made his discovery when he took the lid off, not when he was studying t'interweb.
 

chebby

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Craig M. said:
it's my opinion that the internet will allow people to find out the truth about lots of things, and those who have maintained a certain position will look very silly or corrupt. bring it on.

Quite often it's the 'truth' according to someone who would have to order clothes on the internet just to leave the house. (Assuming they could clear a path to their door through the immense piles of pizza boxes.)
 
A

Anonymous

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Congratulations on the succesful repair. Luckily it's not all rocket science :)

MajorFubar said:
The volume control is connected to the pre-amp board via nothing more high-brow than a 6" piece of ribbon cable, like you find in desktop computers. Removing it, cleaning all the contacts and refitting it restored my missing channel.
Naturally I don't know the design of that model, nor which connector you pulled, but if it was a pre-amp board, then most likely it did not carry any high-voltage signals and might not have carried any audio signals at all. But most importantly: for internal wiring, the length and (hence) impedance is known in advance, so the circuit can be designed for that specific load.

Keeping with wiring: have you ever considered the width of connections on circuit boards, or the complexity of it? Modern processors can easily have a thousand connector pins per square inch, most carrying signals at over 100MHz. Yet it still works :)
 

Craig M.

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chebby said:
Craig M. said:
it's my opinion that the internet will allow people to find out the truth about lots of things, and those who have maintained a certain position will look very silly or corrupt. bring it on.

Quite often it's the 'truth' according to someone who would have to order clothes on the internet just to leave the house. (Assuming they could clear a path to their door through the immense piles of pizza boxes.)

i'm talking about the sort of things an engineer might consider to be 'true', y'know engineering facts and stuff.
 

Lee H

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Craig M. said:
i'm talking about the sort of things an engineer might consider to be 'true', y'know engineering facts and stuff.

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Anonymous

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MajorFubar said:
The volume control is connected to the pre-amp board via nothing more high-brow than a 6" piece of ribbon cable, like you find in desktop computers. Removing it, cleaning all the contacts and refitting it restored my missing channel.

So irrespective of your opinion of specialist interconnects, speaker cables and 'audiophile quality' electronic components, it's food-for-thought that after all your efforts, internal key parts of your HiFi's audio-chain are linked together with nothing more than thin ribbon cables.

And the circuit boards have tinned copper tracks etc., and all those components chosen on a cost basis. And you should see _inside_ a volume pot - a feeble copper wiper dragging on a carbon strip!! In fact my next integrated amplifier will not have a pot at all, or a stepped attenuator, or a level transformer, and will sound better for it.

Even the legendary Naim NAP250 sent all it's sound out via a 0.22R resistor - a little coil of fine resistive wire soldered onto the board. Luckily for the NAP250 physics and electronic design principles are still intact so it worked just fine.
 

Andrew Everard

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Craig M. said:
i'm talking about the sort of things an engineer might consider to be 'true',

Ah right, you mean like 'Michael McIntyre is hilarious', 'Cheryl Cole is a babe', 'beer is better when it has bits in the bottom' and 'girls really fall for that line-of-pens-in-the-top-pocket look'
 

MajorFubar

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The_Lhc said:
If it's an electronic volume control it's not carrying any signal (I'm not even sure it is if it's a pot to be honest), so the quality of the cable doesn't matter.
No it's just a basic analogue pot carrying audio signals, not a digital device.
 

Sliced Bread

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Have you also seen the flimsy bits of wire connecting your drivers to the crossevers / binding posts inside your speakers?

They definitely carry some current, but most of the ones I have seen look like a very thin and cheap!

I've wondered about changing them over at some point to match the speaker wire in use to see if / how that effects the sound. It won't be until the warrantee runs out though!
 

Excitable Boy

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Andrew Everard said:
Craig M. said:
i'm talking about the sort of things an engineer might consider to be 'true',

Ah right, you mean like 'Michael McIntyre is hilarious', 'Cheryl Cole is a babe', 'beer is better when it has bits in the bottom' and 'girls really fall for that line-of-pens-in-the-top-pocket look'

Andrew - have a :beer: - you are a top man ! Made me laugh out loud at work !! :clap:
 

naughty573

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well really to me those thin cables are not a huge matter for concern when you consider that your amps and other electronic components all use circuit boards that carry signals across tracks that are so small and thin that they can only accomodate voltage and current that are measured in small decimal points

some of those are so thin that even bending the circuit board whilst removing it for repair etc could easily break those tracks and render the entire unit inoperable ..... so considering that i dont think that some seemingly thin (but possibly) high quality cable somewhere in the mix is the potential weak point (or even potential point of failure/point of poor performance) in the unit
 

marou

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Craig M. said:
it's my opinion that the internet will allow people to find out the truth about lots of things, and those who have maintained a certain position will look very silly or corrupt. bring it on.

You seem to have touched a raw nerve, Craig - not sure where AE thinks we're reading this
 

Andrew Everard

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marou said:
You seem to have touched a raw nerve, Craig

Not at all: that poster has been saying this stuff for ages, as his signature suggests, and it's all getting a bit tinfoil hatty and amusing.

marou said:
not sure where AE thinks we're reading this

Not even sure AE knows what that bit means.
 

marou

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Andrew Everard said:
Craig M. said:
it's my opinion that the internet will allow people to find out the truth about lots of things, and those who have maintained a certain position will look very silly or corrupt. bring it on.
Aliens, secret world government, what really happened in the bunker in Berlin, who killed Marilyn – all pretty downbeat stuff...

And totally misses the point that the OP made his discovery when he took the lid off, not when he was studying t'interweb.

And you rather missed the point that the internet was where the OP chose to announce it.
 

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