1)No, but usually yes.
4)What arm are you using, perhaps it is a resonance? How are you measuring this BTW?
5)Yes, yes and no.
1. A dedicated phono cable is usually lighter guage than a std. IC to carry that minute signal. It generally uses two identical conductors for signal-- which might not necessarily be true of a general-purpose IC, where shield could be functioning as a return or be connected to the return at both ends of the cable. But I don't think there is any rule about this.
2. The ground wire to the TT is not an electrical ground. It is a chassis ground. So in connecting it you may have some small relief from RFI and potential problems with static electricity.
3. A phono cartridge is not strictly a balanced source; it is sometimes called a floating balanced source. Just two conductors per channel in opposite phase from each other (representing the ends of a coil), and no electrical ground. Neither end of the cartridge coil has an inherent ground orientation, just an inverted phase relationship in AC with respect to the other conductor (like a loudspeaker). By converting it to an XLR plug you are not really getting the benefits of a balanced source, but may be losing up to 6db to noise(as per prior Audio Asylum post by Victor Khomenko of BAT).
Rather than use an RCA/RCA-to-RCA or RCA/XLR converter, I suggest eliminating excess metal and metal-to-metal contact with a cable terminated DIN-to-RCA or DIN-to-XLR (Assuming your arm has a DIN plug.)
4. I too have a Helikon, which I prefer loaded down with 100R in a BAT P10 phono stage. Subjectively I'm not hearing your 10kHz peak, but I have not taken measurements. Possibly room effect??
5. Please clarify your speaker binding post arrangement. The purpose of biwiring is generally to separate the treble & bass arrays via separate cables back to the amp. Leaving jumpers between the w & t binding posts would defeat the purpose but would not be harmful.
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.
Your methodology is pretty flawed, but you have a great table there. You are measuring your in-room frequency response, more or less. Try going from the phono preamp directly into a voltmeter or scope. This way you will be measuring the response of the phono system, not the loudspeakers and room. You may be quite surprised how linear it really is. You may also want to back off on the vta a touch to make the sound a tad mellower. If it is the in room response and not the phono then room treatments and speaker positioning will probably be the better solutions.
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.
I bought my Hovland phono cable a long time ago and had it terminated DIN to XLR for the BAT P10 prior to reading Victor K's remarks about the preferability of an RCA connection into a phono stage-- a balanced phono stage. I may reterminate the cable RCA. The Hovland people also told me that their cable would sound better with RCA than with XLR, particularly when a low-mass plug such as Tiffany is used.
Inside the balanced phono stage a fully differentially balanced circuit can be derived from a single-ended source and passed to downstream components.
Not sure how your custom cable handles ground. You might just try running a separate chassis ground wire from the TT to the ground post on the phono stage. It probably won't affect the sound.
Not sure what you mean about the speaker jumpers. Are you saying you've biwired the speakers but you prefer the sound with the jumpers in? If so, you've defeated the biwiring and you are not hearing the biwire speaker cables as they were designed to work. But it's also possible that the speakers sound better when not biwired.
As with anything having to do with audio, there are no hard and fast rules. I think you just have to continue to do what you have been doing, which is to experiment. I had a Helikon, but, at that time, I also had a phono stage with a fixed 125 ohm loading. It seemed to work well with this phono stage.
With my current Titan, I actually run it almost wide open (47k ohms). This gives me a very extended top end and a better sense of hall sounds. I tame some of the top end sibilance by setting VTA very slightly low (tail of the cartridge pointing down). I find Lyra cartridges to be quite sensitive to VTA changes. It is surprising what even 1/2mm of height at the pivot makes.
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).
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.
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.
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:
Dear Dave: I agree that the cartridge is not a balanced item but it is not single ended either, the cartridge is a signal generator: that's all.
The point on the subject reside on the phono cable to take advantage of the balanced input in a true balanced phonolinepreamp.
Any one can tell me how I can post a picture/diagram here for explain about?
Regards and enjoy the music.
Several years ago I switched from a Helicon to a Titan on my Rockport and at least in the Rockport arm, the Titan is significantly better. Cleaner at the top and definitely more bass but in my system the greatest improvements were in dynamics and presence. Perhaps the Titan is just a better match for the Rockport arm but in my system significantly better.
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!!