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Phono inerconnect

Posted: 25 Apr 2004 19:17
by rems
Hi all!

I just bought my first turntable, and I now need two things :

First head/cartridge; second cables.

I want both head and cartridge so that I can leave the old assembly on the turntable when I am not at home so that the kids (girlfriend and house-mates) can play with it... Now I wonder what should I use for MY listening enjoyment. I am very budget minded, so I was thinking about a sub50$ cartridge. What could be the "less-worst"?

Second : I bought the turn table (Sansui sr-222) with (iguess) original cables.
They are RCA -> RCA. All phono cables I found on the Web had RCA at one end, and a single plug ( = ?) at the other. Should I use regular analog interconnect + homemade ground? I figure there is something I don't understand here... feel free to correct me!

Note that I run a very basic mid-fi setup : AMC integrated amp with Energy XL:16 speakers + monster z-series cables. I only ask for the TT to keep up with the already existing equipment.

I will also get brushes (lp brush, stylus brus), alignment tool, balancing tool and anti-static fluid.
Thinking about thickening damping fluid (eventually).

So if you could help me with the cartridge/head and calbe issues, and give me any phononewbie advice, I would appreciate.

looking on enjoying the forum with you all!

Posted: 25 Apr 2004 19:48
by mosin
Here's a link to DIY cables. I find that the cables outlined here beat most anything around, and for very little cost.

Posted: 25 Apr 2004 20:16
by Guest
Not much likely to be wrong with the SR 222 cables.

Cartridge does depend on which version of the Sr-222 you have.

I've a feeling the Grado Black is probably your
best bet, for a rich tonal balance with good bass. ... /id.244/.f

A magnesuim headshell is also recommended as is a carbon fibre brush.

Not sure where you are going with the damping fluid.

:) sreten.

Posted: 25 Apr 2004 20:45
by rems
sreten wrote:Not sure where you are going with the damping fluid.
Not shure either! I thought the fluid was supposed to go in the lowering mechanism... Then again : it is all new to me, I could have misunderstoud something. Anyways, that is not the most important thing!

About the interconnect : I gave a look at the link given by Mosin... I don't understand (english is NOT my first language -- wich might not help -- and this analog stuff is all new to me :oops: ).

To make my way to understanding, I will ask a simple, straight forward question : with two RCA interconnects to my integrated amp, do I have to set a third, simple wire wich would be the ground?
If yes, how do I choose this particular wire -- anything special about it?

One last thing : sreten, why magnesium? Aluminiun won't do it? What is the difference?

Posted: 26 Apr 2004 11:56
by jvo
Most 222's came with a 11g- arm or heavier. This asks for low mass and/ or humble compliance.
Grado carts have been designed for a total effective mass of 12 to 17 g. Most cartridges are 6 g. This brings the total weight on 18g, which is outside the region preferred by the manufacturer.

Grado carts are warm sounding indeed. If that is what you want, the model Ortofon OMB10 would perhaps be a bit too vibrant, but mechanically seen, with a mass of 2.3 g and a 20 cu compliance in practice, it would be very compatible. A spare headshell would not be a problem. They can be had at many places.

The cheapest Sumiko carts have low compliances too. And AT95 E would be a good candidate, if you like your music played in a clear , bright way.

Stanton 500A could be a good candidate too. This one really sounds warm.

When you could find a relatively cheap Ortofon Concorde cartridge or a Stanton equivalent you could have low weight and low compliance together in a user- friendly combination.

Posted: 26 Apr 2004 13:46
by Guest
Usually the extra ground wire is a must, for low noise / hum,
nothing special at all, just a plain unshielded piece of wire.

Magnesium is better than aluminium, but its not a must.

:) sreten.

Posted: 26 Apr 2004 14:11
by rems
Great! thanks to you all for your help

One last thing : could anyone explain the difference between balanced ant unbalanced cables?

I read over ant over again the page wich I have been refered to by Mosin, and can't figure the difference... And : wich type do I need?

Posted: 26 Apr 2004 21:03
by jvo
Normal connection type is unbalanced. So unbalanced is what you need.

An UNBALANCED system is based on the following principle: all points with ground potential in the entire system are connected to one of two cores in the cable. (zero volts)
The other one describes the analogue signal: a alternating voltage which can have negative and positive potential seen by the ground - connected first core.

Talking about the BALANCED set of connections: one of three cores in the cable has been connected to all ground potential- points in the system.(zero volts)
The two others together describe the alternating voltage sound signal as a potential difference between each other in negative and positive sense, just as it must be to have sound reproduction.
But doing that they obey to ONE continuing condition: they have such voltages that the first mentioned ground- connected core has a potential positioned exactly halfway the two others.(zero volts as we had seen)

Have lots of succes with this nice 222.

Balanced & Unbalanced

Posted: 27 Apr 2004 01:00
by Steerpike_jhb
That Bal/Unbal explanation I thought missed the point somewhat (sorry to criticise).

Unbalanced lines are the commonly used kind in home audio, A single screened conductor for each channel. The inner conductor carries a voltage that swings alternatively positive and negative with respect to the outer screen - which is also system ground.
Interference immunity is a problem because the screen needs to be discontimuous for flexibilty.

In a balanced line system - as used in studios, each channel is carried on a PAIR of conductors within a single screen/braid. The source is such that the two conductors swing in opposite direction (electrically) at the same time. When conductor A swings positive, conductor B swings negative, and vice versa.

The amplifier input is special in that it is 'differencing amplifier'... It amplifies only the difference between the two inner conductors. Any interference picked up by the CABLE is picked up simultaneously by BOTH conductors, and so is rejected by the amplifier.
The advantage is very high noise immunity, especially on long cables.
It only improves noise pickup in the cabling, and is of no help if the source is noisy.

Pick up cartridges are inherently balanced sources, although (sadly) they are almost never wired up to exploit this characteristic. Very few amplifiers (outside of studios) can accept balanced sources.

Posted: 27 Apr 2004 08:25
by jvo
IMO what I described were the basical requirements. The only weakness of my explanation was that the zero- potential core was the screening. In both systems.
Just re-read my description and you will conclude that it mentions the most important principles, apart from the screening- issue.

Balanced / unbalanced

Posted: 27 Apr 2004 12:42
by Steerpike_jhb
Yes I agree you described the principle and operation correctly. But you didn't mention the main reason for using the more expensive balanced system - which is its immunity from interference and noise induced into the cable.
True, on very short runs like 1m the difference will be marginal, but I have noticed quite a few people posting problems about hum pick-up and earthing.
Balanced interconnnections make this much less of a problem.

Posted: 27 Apr 2004 17:37
by rems
Mosin :

I found a place to get the Belden cable mentionned by Jon Risch. It now seems that Belden offers a more flexible version of the 9913 coax.

In think this is a very interresting solution, and might as well make myself some good quality jumper cables (from pre-out to pre-in)...

It is double-shielded... In the soldering of such a cable to the rca connections, should both shields be soldered, or only the inner or outer?

Posted: 28 Apr 2004 05:46
by mosin
I used the same cable to make mine. I soldered both on one end, but left the shield unsoldered on the other end. As a result, the cables are directional. In my case this was a good solution because I got some hum otherwise, due to excessive length of the cables in my system.

There are instructions at Jon's site for doing them this way.