Unshielded IC's

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mick wolfe

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Unshielded IC's
« on: 30 Apr 2012, 02:27 am »
Well my Amadeus is up and running and of the IC's I've tried so far, I like the Morrow MA3. Unfortunately, it's unshielded and despite its sonic advantages, the hum is a bit much. I've heard of cable wraps and shielding sleeves and wonder if this approach might be a quick, cheap and easy fix. I really don't want to start shopping for phono specific cables if I can avoid it. Thx for any input.

roscoeiii

Re: Unshielded IC's
« Reply #1 on: 30 Apr 2012, 04:52 am »
With signals so small, I think you are going to need to get a shielded cable. Not much more to say about that. Not sure why you thought you could get around that requirement. That said, shielded cables with characteristics best suited for phono signals don't need to be expensive (but they sure can be).

mick wolfe

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Re: Unshielded IC's
« Reply #2 on: 30 Apr 2012, 06:25 am »
With signals so small, I think you are going to need to get a shielded cable. Not much more to say about that. Not sure why you thought you could get around that requirement. That said, shielded cables with characteristics best suited for phono signals don't need to be expensive (but they sure can be).

Despite the fact that it is unshielded, I had to give the MA3 a shot to see what it could do sonically. Hum and all, this was the best sounding cable I tried. And yes, the phono version of the MA3 is expensive.

roscoeiii

Re: Unshielded IC's
« Reply #3 on: 30 Apr 2012, 06:34 am »
Yeah, doesn't (usually) hurt to try. But some laws of physics can't be overcome. And you might hear a little "I told you so."

But on the more helpful end of things, can you give an idea of your ideal budget for a cable so that some helpful suggestions can be generated?

dhrab

Re: Unshielded IC's
« Reply #4 on: 30 Apr 2012, 12:39 pm »
Don’t know if this will help or is worth it ... http://www.zippertubing.com/EMI-Shielding-Tapes.aspx

EMI/RF shielding tape that you can maybe wrap around the phono IC ... not sure how effective or expensive .. but worth a look at

jsawyer09

Re: Unshielded IC's
« Reply #5 on: 30 Apr 2012, 01:15 pm »
Yeah, doesn't (usually) hurt to try. But some laws of physics can't be overcome. And you might hear a little "I told you so."

But on the more helpful end of things, can you give an idea of your ideal budget for a cable so that some helpful suggestions can be generated?

Yeah, the Morrow phono version is expensive, but worth it. Actually, it's all relative, as I don't think it's all that expensive compared to the competition out there. Phono cables are expensive, IMO, period (comparatively speaking).

You could try Grover Huffman's phono, which is outstanding — and pretty cheap. I used Audioquest Colorados for a while and thought these were the best at eliminating any source of hum (but they're really expensive, unless you buy used). I currently use some cheap 'ol Mogami 2534 ICs with Vampire RCAs...I cannot believe how great they sound; and they eliminate almost every trace of hum on my Amadeus.

mick wolfe

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Re: Unshielded IC's
« Reply #6 on: 30 Apr 2012, 04:09 pm »
Speaking of unshielded cables I tried, the Grover was in the mix as well. BTW, where did you source the Mogami and is it still available?..Thx

roscoeiii

Re: Unshielded IC's
« Reply #7 on: 30 Apr 2012, 04:13 pm »
Mogami is available a lot of places. And it is used a lot in pro audio, so pretty cheap. I had these guys build me a couple custom cables, and I think I chose Mogami for the wire. Maybe give them a ring:

http://www.kvconnection.com/

I will leave it for more technically knowledgeable folks here to tell you what characteristics you will want in a phono cable other than it being shielded.

mick wolfe

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Re: Unshielded IC's
« Reply #8 on: 30 Apr 2012, 04:22 pm »
Yeah, doesn't (usually) hurt to try. But some laws of physics can't be overcome. And you might hear a little "I told you so."

But on the more helpful end of things, can you give an idea of your ideal budget for a cable so that some helpful suggestions can be generated?

Well Roscoe, as you probably already know, there has been more than one "inmate' over at AudioAsylum(Vinyl) claiming to be using unshielded IC's in a phono application with no problem. Hence the laws of physics had to momentarily be kicked to the curb. Only to of course rise up again and "hum" to me.

roscoeiii

Re: Unshielded IC's
« Reply #9 on: 30 Apr 2012, 04:26 pm »
Huh. I must have missed those claims on the Asylum (or repressed my memory of them). Lucky folks if that is the case for them.

jsawyer09

Re: Unshielded IC's
« Reply #10 on: 30 Apr 2012, 04:42 pm »

Well Roscoe, as you probably already know, there has been more than one "inmate' over at AudioAsylum(Vinyl) claiming to be using unshielded IC's in a phono application with no problem. Hence the laws of physics had to momentarily be kicked to the curb. Only to of course rise up again and "hum" to me.

FWIW, have the gents at Pro Audio LA make you up a pair. They did an excellent job on mine. You could try a meter of the quad cable (2534) or any other type. Some say short runs of the quad are better for balanced, but I can't hear a difference. All I know is it sounds awesome and does the job as an excellent shielded cable. I recommend it...also, like I say, you'd be out nothing (or, next-to-nothing).

cheap-Jack

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Re: Unshielded IC's
« Reply #11 on: 30 Apr 2012, 06:11 pm »
Hi.
Quote from: mick wolfe link=topic=105951.msg1084115#msg1084115 date=1335752running and of the IC's I've tried so far, 828

 I like the Morrow MA3. Unfortunately, it's unshielded and despite its sonic advantages, the hum is a bit much.

I suggest you to contact Morrow Audio to find out why it hums.

With signals so small, I think you are going to need to get a shielded cable. Not much more to say about that. Not sure why you thought you could get around that requirement.

Sorry, I disagree.

Given built properly, an unshielded audio connect should NOT hum at all. Needless to say, it should not be too long. Otherwise, it'd hum even with triple shielding over it. Shielding generates extra conductor-shield capacitance, which rolls off HF. Sonically, the music sound compressed & less lifelike. I hate the sonics of shielded cables.

Take mine for example, the 6 pairs of audio interconnects I DIYed & am using for years, are 4N pure solid silver conductors, NO shiled at all, including 2 pairs of interconnects from my TT to my 2 tube phono-preamps. No hum - provided they are built right!

c-J

PS: Pure silver cables sound superb. But you may ask how come pure silver
cables are rarely available in the marketplace. One practical answer is: way way too costly to build & very dfficult to keep pure silver from tarnishing.
Thank goodness, I know the way to overcome them.

roscoeiii

Re: Unshielded IC's
« Reply #12 on: 30 Apr 2012, 06:31 pm »
c-J you may also be fortunate enough to live in an environment without the nasties (EMI/RFI? not sure) that cause a phono cable to hum.

I am not convinced that any unshielded cable can be built that avoids hum in all environments, particularly in the case of a LOMC cart.

Feel free to send the OT a pair of your cables to prove your case. But the safe bet for eliminating hum is shielded cables.

Never seen any HF roll-off with a shielded cable when using my test record and a high quality SPL meter. I wonder how the cart-cable match might be leading to that rolloff? Or other aspects of the cable specs other than shielding? No expert, but that rolloff strikes me as very peculiar. Since most people will be using shielded cables you'd think that cart and phono pre designers would account for the potential rolloff due to shielded cables and correct for it.

Not trying to be contentious here. Just trying to think through your experience and mine, along with what I took to be the generally accepted suggestion that a phono cable be shielded.

cheap-Jack

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Re: Unshielded IC's
« Reply #13 on: 30 Apr 2012, 06:32 pm »
Hi.
There has been more than one "inmate' over at AudioAsylum(Vinyl) claiming to be using unshielded IC's in a phono application with no problem. Hence the laws of physics had to momentarily be kicked to the curb. Only to of course rise up again and "hum" to me.

Sorry, the "law of physics" is still maintained if one knows it.

Shielding is to keep RFI & hum away at the expense of sonic quality, IME.
Yet, we can still obtain the function of a shield withOUT using it by building the cable right! The reward will be music sound so open up & lifelife.
That is the key reason why ALL the audio interconnects I build & am using get nil shield.
 
Guess how?

c-J


Sonny

Re: Unshielded IC's
« Reply #14 on: 30 Apr 2012, 06:34 pm »
Hi all,

FWIW, I think the "Shielding" effect is all system and area dependent!  I make lots of cables, none of them shielded and they don't hum a bit for me in my system and 99% of my customers and most have no hum issues.  I think it's all due to RFI or EMI...


roscoeiii

Re: Unshielded IC's
« Reply #15 on: 30 Apr 2012, 06:42 pm »
Hi all,

FWIW, I think the "Shielding" effect is all system and area dependent!  I make lots of cables, none of them shielded and they don't hum a bit for me in my system and 99% of my customers and most have no hum issues.  I think it's all due to RFI or EMI...

As long as y'all selling unshielded ICs have a solid return policy, it is all good by me.

Sonny

Re: Unshielded IC's
« Reply #16 on: 30 Apr 2012, 06:44 pm »
Deleted....
Roscoeiii, PM Sent.

threadkiller

Re: Unshielded IC's
« Reply #17 on: 1 May 2012, 12:30 am »
Careful, boys, no selling on here....:)

OzarkTom

Re: Unshielded IC's
« Reply #18 on: 1 May 2012, 01:11 am »
Unshielded cables have always sounded the best to me. I started using unshielded back in the mid 80's.

mick wolfe

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Re: Unshielded IC's
« Reply #19 on: 1 May 2012, 02:33 am »
Hi.
I suggest you to contact Morrow Audio to find out why it hums.

Sorry, I disagree.

Given built properly, an unshielded audio connect should NOT hum at all. Needless to say, it should not be too long. Otherwise, it'd hum even with triple shielding over it. Shielding generates extra conductor-shield capacitance, which rolls off HF. Sonically, the music sound compressed & less lifelike. I hate the sonics of shielded cables.

Take mine for example, the 6 pairs of audio interconnects I DIYed & am using for years, are 4N pure solid silver conductors, NO shiled at all, including 2 pairs of interconnects from my TT to my 2 tube phono-preamps. No hum - provided they are built right!

c-J

PS: Pure silver cables sound superb. But you may ask how come pure silver
cables are rarely available in the marketplace. One practical answer is: way way too costly to build & very dfficult to keep pure silver from tarnishing.
Thank goodness, I know the way to overcome them.

And if I were to contact Morrow, he would simply say  "buy my shielded phono cable"." My standard unshielded cables will be far more prone to hum in a phono application". This is just a guess of course, but I think I'm close.