True Balance Tonearm Cable wiring |
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回覆 (23): True Balance Tonearm Cable wiring
Hi, dear all,  
 
I .C. You are putting money into my wallet.  
 
 
dkyyu
14-02-18
15:35:57
回覆 (22): True Balance Tonearm Cable wiring
If I floated up all the RCA groundings from end-to-end in phono, preamp, power amp design, will I still achieve a full balance cirucit using RCA plugs all the way?  
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it does not work like that. the fact that the cartridge output can be configured like this is because of the nature of the cartridge. all other RCA outputs the two signal lines do not have equal impedance to ground.
drwkng
14-02-18
15:23:15
回覆 (22): True Balance Tonearm Cable wiring
>May I suppose the phono maker can still configure to operate in true balance circuit with true xlr output even solely equipped with RCA phono input.<  
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If I understand correctly, a majority of the so called “full balanced” phonos, including the Aesthetix IO and Pass Labs Xono, actually have single end input stages! They just generate a – signal (at the first or second stage) to make it a balanced signal for the remaining gain stages and output stage! So, yes, you can have a true balanced output with a single end (RCA) input!  
 
thekong
14-02-18
15:20:09
回覆 (22): True Balance Tonearm Cable wiring
Do you mean the RCA -ve will connect to the common ground shared with others such as chassis while xlr only connected to the internal circuit reference grounding?  
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Dear Michael,  
 
If this is the case, there is nothing wrong to Rega sharing the arm tube grounding path with the left channel negative wow. All went to the common grounding ma.
dkyyu
14-02-18
15:18:51
回覆 (21): True Balance Tonearm Cable wiring
If I floated up all the RCA groundings from end-to-end in phono, preamp, power amp design, will I still achieve a full balance cirucit using RCA plugs all the way?  
 
I guess this forum now turns into a learning center for kinder DIY beginer.
dkyyu
14-02-18
15:14:59
回覆 (20): True Balance Tonearm Cable wiring
Happy New Year, dear King sir,  
 
I must add you and CP to the list of to earn my learning fee.  
 
I think I have a clearer picture. Do you mean the RCA -ve will connect to the common ground shared with others such as chassis while xlr only connected to the internal circuit reference grounding?
dkyyu
14-02-18
15:11:21
回覆 (19): True Balance Tonearm Cable wiring
If the answer is yes, what on earth is diagram 13 different to the standard RCA tonearm cable except the xlr plug. I suppose there must be something not common.  
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for a rca connection, one of the line is connected to ground. for a balance connection, both +/- are referenced to a ground ie same impedance to a common ground. if you look at the diagram 13, it does not tell you what happens at the other end, but as it stands, neither lines from the rca are not connected to ground.
drwkng
14-02-18
14:57:46
回覆 (19): True Balance Tonearm Cable wiring
As long as the load is balanced, floating ground is all good  
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Just realised that this may be the answer from Bobui although I have no idea when a balanced load is.  
 
May I suppose the phono maker can still configure to operate in true balance circuit with true xlr output even solely equipped with RCA phono input.
dkyyu
14-02-18
14:51:49
回覆 (18): True Balance Tonearm Cable wiring
Hi, dear all,  
 
Except Rega, I guess 99% tonearms on earth are sharing the same topology of separating the earth wire and -ve apart.  
 
When we considered 2 pin connection per channel when following the diagram 13 which is still regarded as true balance or floating full balance, it seems to me there is a simple way to modify a RCA tonearm cable to true balance just by changing rca to xlr plugs while ignoring or floating the earth connection. Am I on the right track?  
 
If the answer is yes, what on earth is diagram 13 different to the standard RCA tonearm cable except the xlr plug. I suppose there must be something not common.
dkyyu
14-02-18
14:45:33
回覆 (17): True Balance Tonearm Cable wiring
As long as the load is balanced, floating ground is all good.
bobui
14-02-18
14:16:31
回覆 (16): True Balance Tonearm Cable wiring
No matter which side is correct  
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I believe both are correct, why not just say now we have a floating balanced situation.
Derek2A3
14-02-18
14:08:44
回覆 (15): True Balance Tonearm Cable wiring
I am now stuck in the office mostly on Sat/Sun as my boss has taken early retirement lately.  
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Hope you are getting his share of monthly paid!  
 
The answer is Yes, you don't always need all three pins collected to be true balanced. Take a look at the drawing below.  
1. Two wires from the cartridges for each channel. And the ground is defined by two Rs. Its typical balanced phono input circuit layout.  
 
2. The dotted line from the cartridge is the tonearm cable shielding which as Kong illustrated should be collected via a spade to the amp chassis ground.  
 
3. Well, to be 101% sure, make sure you have daiwok modified 103R. OK!  
 
bobui
14-02-18
13:33:42
回覆 (15): True Balance Tonearm Cable wiring
>Are we sure this is still regarded as true balance if suspending the pin 1 connection to the phono preamp?<  
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This is a very technical topic which I am not qualified to answer!  
 
However, there was a long thread on Audiogon with a number of phono designers argued whether a phono cartridge was a true balanced source!  
 
As far as I could remember and understand, the negative side stated that for any balanced signal, you would need a +, a -, and a ground for the signal’s reference. So, a cartridge with only a + and a -, was not a true balanced source.  
 
The positive side stated that a cartridge was really a generator itself, so it didn't need the ground for reference, or it could be referred as a “floating ground”.  
 
No matter which side is correct, I believe the diagram shows the right way on constructing a balanced tonearm cable!  
 
thekong
14-02-18
13:28:14
回覆 (14): True Balance Tonearm Cable wiring
Hi, Limage, thekong and Bobui,  
 
I should have paid your parts in yumcha as a token of appreciaiton for raising my enquiries. however, I am now stuck in the office mostly on Sat/Sun as my boss has taken early retirement lately.  
 
I am think about the feasibility of the drawing by thekong in post 13 but using one-length cable, that is ignoring the din plug. Yes, the Breuer arm tube has a point for ground wire but I assume I 'll need to wire 2 ground cables for serving two channels. am I right?  
 
Michael,  
 
I understand how a pair of RCA phono cable configures. You are absolutle correct that I don't have much idea how the xlr tonearm cable work with the balance phono pre-amp if not following your first diagram. You drawing in post 13 looks close to my thinking, just the exception of din plug. Are we sure this is still regarded as true balance if suspending the pin 1 connection to the phono preamp? just not certain.  
 
Like Limage said, I may consider to keep the run of tonearm cable as short as possible and twisted.  
 
If all si-fu has agreed to posted 13, I may give it a try.  
 
dkyyu
14-02-18
13:03:43
回覆 (14): True Balance Tonearm Cable wiring
If the turntable is not collected to ground, then, no spade collection means no cable shielding. Obvious, right!  
 
Below shows how a Linn is collected to the mains ground via the AC mains wire.
bobui
14-02-18
12:53:11
回覆 (13): True Balance Tonearm Cable wiring
Ok, let take the following diagram as an example, since pin 1 is not connected, I suppose it is pretty much the same as a termination with RCA plug, correct ?  
 
If so, then if I don't connect the spade lug to the phono ground, would the shield still works?  
 
thekong
14-02-18
12:40:18
回覆 (12): True Balance Tonearm Cable wiring
I do not connect the grounding wire from the tonearm cable, does it mean the cable's shielding doesn’t work anymore (i.e. same as no shielding) ?  
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Not necessary. Some turntables are collected to ground and the 5 pins Din middle pin is always collected to the arm tube at one end and the other end sometimes plug in to the tonearm cable shield. More frequently seen on not proper made tonearm cable when you see no spade for ground collection.  
 
bobui
14-02-18
12:19:47
回覆 (11): True Balance Tonearm Cable wiring
Enlighten me here please, if I do not connect the grounding wire from the tonearm cable, does it mean the cable's shielding doesn’t work anymore (i.e. same as no shielding) ?
thekong
14-02-18
11:37:44
回覆 (10): True Balance Tonearm Cable wiring
If grounded the arm tube provide sufficient shielding. Why on earth you would want an unshielded tonearm cable. Surely the tonearm cable is longer than the arm tube and more near other equipment for hum pick up, right?  
 
Shield la! Its not unlawful lor!
bobui
14-02-18
11:25:27
回覆 (9): True Balance Tonearm Cable wiring
 
 
Dennis,  
 
The cartridge output wires run inside the arm tube which should provide sufficient shielding if the arm is properly grounded. For the short runs in open air before the cartridge cables enter into the arm tube, you may have the corresponding wires, (i.e. red with green and white with blue) twisted together to reduce any possible hum pickup.  
 
A separate wire running from any anchor point of the arm may serve as the ground wire for the XLR.  
 
limage
14-02-18
11:08:58
回覆 (8): True Balance Tonearm Cable wiring
Sorry that was my mistake. The re-mastered SACD is meant to the minimum penalty. The max penalty should be Mp3.
bobui
14-02-18
11:05:20
回覆 (7): True Balance Tonearm Cable wiring
Phono cable with no shielding is illegal on earth. Max penalty is forever listen to SACD from re-master up sampling CD recordings.
bobui
14-02-18
10:58:19
回覆 (6): True Balance Tonearm Cable wiring
Hi Dennis,  
 
Are you referring to those very thin wires? If so, I think they are meant for internal wiring inside the arm! For external wiring, I would suggest using a cable with shielding and external jacket instead! However, if you insist, I believe those wires would work!  
 
While you better double check with tech guys like mdlover, I think you can ignore the shielding first, and see if there is any hum and noise. If there is no hum and noise, then you are fine. Don't forget to turn your preamp’s volume all the way down first when doing the test, because the hum can sometime be seriously loud (as experienced in our recent phono shootout)!.  
 
To be honest, looks like you really have no idea about these things, so I would suggest asking one of those tech guys to make the cable for you instead!  
 
thekong
14-02-18
10:35:22
回覆 (5): True Balance Tonearm Cable wiring
Morning Michael,  
 
I only have several 1-meter length bare UK Audio Note silver wires (bought from Elephant, should be genuine AN) with transparent coating in hand for phono cable diy-ing. After studing your diagram, I think I need to source or diy the cable jacket myself to shield the +ve and -ve bare wires for both channels.  
 
Given there are only 4 different color coded wires coming from the cartridge, can I simply ignore the ground shielding and the xlr earth connection to save me from the fuss? Will this still regard as true xlr connection if the earth is being ignored in the xlr phono cable?  
 
Sorry for my low-end enquiries.
dkyyu
14-02-18
09:53:42
回覆 (4): True Balance Tonearm Cable wiring
Dennis,  
 
The shielding is already present in many cables, no need to DIY!
thekong
14-02-17
21:32:15
回覆 (3): True Balance Tonearm Cable wiring
Thank you so much, Michael and Ivan,  
 
I still need to figure out how to diy the shielding. My first step to DIY classroom.  
 
Regards  
Dennis
dkyyu
14-02-17
21:20:09
回覆 (2): True Balance Tonearm Cable wiring
 
 
Dennis, the color code goes like this just in case you have doubt:-  
 
 
R: red, right channel +  
 
G: green, right channel -  
 
 
W: white, left channel +  
 
B: blue, left channel -  
 
 
 
but I found all 3 adaptor pins have attached to a wire where I am unable to open the cable jacket to find out how theses 3 connections work  
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Simple, use a multi-meter to check the connectivity through the Ω jack.  
 
limage
14-02-10
15:08:46
回覆 (1): True Balance Tonearm Cable wiring
Dennis, try this
http://www.ayre.com/acc_phono_schematics.htm#phdin
thekong
14-02-09
20:14:39
True Balance Tonearm Cable wiring
恭賀新禧, 萬事如意,  
 
Can any brother enlighten me or point me to how to wire the cartridge's R/W/B/G connections to a pair of 3-pin xlr plugs for proper connection to a true balance phono amp? Please assume 1 is earth, 2 is +ve and 3 is -ve.  
 
BTW, what's the key issues needing attention when DIYing a balance tonearm cable for a ordinary tonearm eg Linn or SME apart from the xlr connection. Forget Rega.  
 
I also bought the rca to xlr adaptor from Aqvox to allow balance mode connection for rca tonearm cable, but I found all 3 adaptor pins have attached to a wire where I am unable to open the cable jacket to find out how theses 3 connections work. Quite confusing.  
 
Thamks in advance.
dkyyu
14-02-07
17:44:08
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