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Phono cable/grounding/loading questions

Hi, I am finally settling with my analog set up which I run in balanced(RCA @ TT end with ground wire and balanced at phono pre-amp, balanced from phono to preamp..)configuration. I do have some questions that I need answered to convince me what is right. I have looked in to archives but have not found clear cut answers. So here goes:

1. Is the purpose fully designed phono cable always better than the regular ics used as phono cables?
2. If there is no hum present without ground wire connected at TT end, technically is it correct to do so? (When I connect the gorund wire, the presentation a little more articulate but on brighter side)
3. Could I use phono cable with RCA/RCA and use RCA/balanced adapter at phono preamp end? Would I be getting full benefit of balanced configuration this way?
4. My helikon cartridge loading with all new burn-in cables sits at 40 ohms currently and there is still peak (4-5 db) at 10 K hz. Rest of the spectrum very good but this peak is annoying at times. Why is this happening?
5. Bi-wire question: Is it okay to use biwire speaker cables with Jumpers or is it defeating the purpose? More importantly is this dangerous?

Sorry to load you with too many questions but I wanted have only one thread to put my mind to rest.

Thanks in advance!!
nilthepill

Showing 4 responses by nilthepill

nilthepill OP
842 posts
 
Viridian, Thanks for clear cut to a point answers.

In response to item 4) The arm is SPJ that came with La Luce turn table. I believe the arm is very good. I am using Cardas freq check LP (there is 10 K HZ track and 30hz-30khz freq sweep among others)-and using Radioshack SPL meter. To be fair, the overall sound is more like neutral. The peak I mentioned is on max side, lowest peak being may be 2 db (you see the SPL meter flickers within 3-4 db during 10 k hz tone).

It may be that since the cartridge selection my taste has changed towards sound where high freq is rolled off a bit.
May be Cardas GR phono cable is the answer. ( which I tried few months back)Disconnecting ground wire reduces high freq to more neutral but boosts bass and reduces transparency. May be the new cables are not completly broken in yet.
nilthepill OP
842 posts
 
Dgarretson, Looks like you and I posted above responses about same time.
1) Thanks for the technical insight.
2) Good. I just disconnected the ground wires and sat down for critical listening sesson. What do you know, the sound 'fell' in to place!! The highs are more realistics, midbass warmer and actually due to contarst the sound is more transparent!! Believe it of not with ground wires off the 10 Khz peak went flat. Bass has 2 db peak than before, but I can handle that.
3) I don't have din plug but RCA jacks at end of tonearm wires. That is why I had cable specially made-ground wires added at RCA/RCA end and balanced at phono preamp end. If cartridge in inherently not balanced, what is the purpose of balanced phono stages? Sounds like your phono is balanded too (BAT), How have you connected at phono input?

4) I have 100 ohm resistors on order from clearaudio, just in case, But 40 ohm may just work fine. But as I said connecting ground wires gets this 10hz peak and may be slightly lower peaks progressively from 1 k all the way to 10 k hz making the sound brighter overall. My ears and measurements don't lie.

5) It seems I may not have use jumpers, since bass is back. thx to burn in completion and ground wires off.
nilthepill OP
842 posts
 
Viridian, I listen in nearfield position to get most of the room effects out. While SPl meter is not the best way to measure/confirm what I hear, it is ths only way I got. VTA angle change is a good suggestion, which I might try.

Dgarretson, I am not sure my phono (clearaudio balanced reference) can activate both RCA in, balanced out mode as there is a switch for either balanced/unbalanced selection. But it does not hurt to try.

I am not sure how my custom phono/ic is wired but I asssume the ground cable from TT end continues on at the balanced end. I will check with mfr. It is curious though that the sound really changes with ground wire connected or not at the TT end. The difference is not subtle!

Larryi, I know this is differnt topic but how does helikon compare with Titan in overall sound balance?
nilthepill OP
842 posts
 
Larryi, You are so right! Finally I gathered all the courage to fiddle with VTA. Ofcourse after reading very precise instructions written in my manual. It does say that don't assume 'factory set' VTA is always right, since the cartridge heights are different and is not industry goverened, and that the cutters angles are different depending upont record labels, slight change in VTA is necessary depending upon the cartridge. 5.3 turns of the micrometer changes the angle by 1.25 degs and it recommends to try this setting. Lucky for me I can adjust the VTA while record is playing. Try I did and sure enough slight sibilance I had left over when I disconnected the ground cable was gone and sound changed dramatically (I could now bear 47k loading sound v/s absolutely earshattering sound before).

It tunrned out that at current 40 ohm loading though, these many turns actually 'blunted'the sound so I found a good balance at about two turns , cartridge tail down. When I get 100 ohm resistors I will play again with VTA adjustment. Thx for thr tip!!
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