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
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?
The Titan has more weight in the lower bass and is not quite so edgy sounding as the Helikon. It sounds more relaxed, but it certainly is not lacking in detail or dynamic ability. I prefer the meatier sound of the Titan, but I think the Helikon is no slouch.

But, when I changed the cartridge, I also changed tonearm to the Vector. According to Lyra, the Titan's titanium alloy body transmits a lot of vibrational energy from the cartridge to the tonearm, putting a lot of demand on the tonearm to effectively dampen and/or bleed off such energy instead of reflecting it back to the cartridge. The Vector is very good in this regard. I don't know how the Titan would compare with the Helikon in my original arm (Graham 1.5t). I heard the Titan in a newer Graham 2.2 arm and that combination also worked very well.

So much is system dependant, but I should mention that a friend is trying a Transfiguration Orpheus in place of a Helikon. The Orpheus sounds great in his setup (Graham 1.5t on a Mk IV VPI). The Orpheus has the same extended, smooth and airy top end of the Helikon, but substantially more weight in the bass (his horn-based system is lacking in very deep extension so this additional weight is synergistic. This cartridge is lively and dynamic without being edgy or harsh sounding. I will get a chance to hear the Orpheus in my system once I work into my system a new linestage and phonostage (Emotive Audio Epifania linestage, Viva Fono replacing the Levinson Ref. 32 preamp).
Larryi,

I agree about the Helikon's lighter bass (with my Graham 1.5tc, which is also a little shy in the low bass.) I find it's possible to contour up the bass with a good sub like the Vel DD-15 and am surprised how articulate and linear the bass region now sounds in my system. Sub has one preset EQ for CDP and another for TT. Wouldn't refuse a Titan, tho.

Dave
Dear Nilthepill: 1 - Usually are better but not always. The regulars, that come with the tonearm, are usually good but not the " best ". The tonearm manufacturer only ( till today ) give us and starting/first cable step on the very long cable ladder and certainly not the " best one " because its tonearm has to have a precise level price point and if he choose a higher price cable his tonearm could be out of price market.

2 - In my experience the whole system has to be grounded at one and only one point ( usually at the phonolinepreamp through a dedicated true earth ground line. ) to avoid ground loops and to avoid what is happen when you grounded at the TT end.

3 - The only way to take advantage of a balanced operation phonolinepreamp is that the cable from tonearm to the PLP has a balanced connector/connection.

4 - Viridian give you the right answer about.

5 -I agree with Dave about.

Regards and enjoy the music.
Raul.
Raul,

The BAT phono stage has both RCA & XLR inputs but ONLY balanced outputs. The RCA input is inverted within the phono stage and passed through differentially balanced amplifiers for true balanced output to the preamp. As I mentioned above, a cartridge is not a true balanced source. There is no third ground pin, no inversion of +/- with reference to a ground, no common mode noise rejection. So the matter comes down to whether to use the XLR connector or the RCA connector into the balanced phono stage. The XLR input will divide the output current of the coil between the differential amps and produce a lower SNR than an RCA. A low-mass RCA plug (Nextgen, Eichmann, etc.) may also sound better than XLR due to the XLR's heavy metal barrel.

This issue has been covered in several threads elsewhere. Here is a good one for background:

http://db.audioasylum.com/cgi/m.mpl?forum=vinyl&n=111640&highlight=phono+balanced+connection&r=&session=

Regards,

Dave