Thats a VERY long phono Cable, why not move your phono pre next to your turntable and then run a line level balanced interconnect to your preamp instead, this would be a much preferable set-up
Good Luck
Peter |
I'm not sure you can even do this. Those phono signals are extremely tiny and don't do well with long cables. Are you using this long a cable already? If you are in the Graham Phantom world then you likely will be using a LOMC which makes things even worse at less than 1 millivolt output. I even noticed sound degradation from going to a 2.5 meter phono cable with 5 millivolt output cart. |
If the preamp accepts the phono signal differentially, then you stand a very good chance of making this work, especially if the cartridge is loaded at something less than 600 ohms.
This will create a low impedance balanced line, and will be quite immune to the cable length. Although the voltage output of the cartridge is quite low, the current is rather robust, else so many LOMC cartridges could not drive 100 ohms or less!
Now its my opinion that if you are placing the turntable in a particular location to minimize vibration, you should consider placing the preamp in the same location for similar reasons. The preamp *should* be able to drive long cables if its balanced (if it can't IMO you need to think about a different preamp- our preamps can drive over 100 feet with ease, like any balanced preamp should). So I would think in most cases that you would not need to run a long phono cable, but it is possible. |
Atmasphere, you got it right. Main reason for this is to move the turntable away from my electrostatic speakers. I guess I will minimize vibration and also will remove the bulk of a very big turntable, acrilic case included, from between the speakers, therefore improving sound image.
My phono pre accepts XLR inputs. I do not have a pre-power combo, instead I've got a lovely integrated that cannot be splited into two :-).
My cartridge is an Ortofon A90 and the phono pre is an allnic H3000. I don't know what you mean by "if the preamp accepts the phono signal differentially". Could you please extend a little bit.
Thanks to all for your answers. |
I have an Allnic H3000 and it does not have xlr inputs. It has xlr outputs. Did you have xlr inputs added as an option?
I see no reason why you could not just put the Allnic by the TT and run xlr from it to your intergrated amp. |
FWIW, Planar speakers have virtually nil radiation to the left and right of the panel, in a plane with the panel. So, you can probably get away with mounting your tt and preamp near the speaker, if you can place them in the plane of the speaker panel. (Hope this is clear to you; if not, I can try again.)
Allnic H3000 is an interesting beast. I do not know for sure that it treats the cartridge output in true balanced differential mode (presence of RCA inputs does not rule this out). As you or someone else said, it does have XLR outputs and the literature does speak of balanced output circuitry, but could be done via an output transformer. I own an Atma-sphere MP1, but I must say I would not consider trying to use 24 ft of phono cable, even if Ralph does bless it. |
Very bad 2 mtrs should be max.This is a very low level signal 21Ft is very bad nobody runs 21Ft on Phono. |
Jbuenech, if the XLR input is done via a StepUp Transformer, then you will get the benefit of a proper balanced input as the Common Mode Refection Ratio at the input should be quite respectable, this so long as the SUT is tied to pin 2 and 3, and ignores ground. |
Sarcher30, you are right. When I tried with a shorter cable I found out that XLR was the phono pre output, not the input. As my integrated amp does not have Balanced inputs, my only option is to put the turntable between the plane of the speakers, as Lewm suggests.
Thanks to all of you for your contributions¡ |
Dear JB, Dipoles radiate in sort of a figure 8 pattern where the pinched part of the "8" represents the radiation at the plane of the speaker, and the two top and bottom loops represent the radiation patterns in front of and behind the speaker. So you should be ok. This is also why you can get away with having the outer edges of the speakers very near to side walls. |
Dear Lewm, I have tried your suggestion and it has brought a big improvement to the sound image and, surprisingly, to the tonal balance, now with less enphasis on the higher frequencies. I guess the turntable huge acrilic case was acting as a resonance box.
Unfortunately my wife is not so happy because I have brought the music rack (double width and quite high) also 5 feet into the room to be aligned to the speakers plane and this is our living room as well :-). So far I got permision, so lets enjoy it.
If in the future I evolve to a Pre-Power combo I'll be able to move the phono pre together with the turntable to a side space, following the recommendations to other posters.
Thanks to all of you guys! |
Jbuenech if your preamp can drive long interconnects then the equipment stand need not be between the speakers. Did I read it right that the Allnic has balanced outputs? |
Atmasphere, the Allnic has balanced outputs, but my integrated amp does not have balanced inputs. It only handles Unbalanced. |
Not to hijack this thread, I just offer this as an option to Jbuenech's similar dilemma. I am a bit of a newbie on this site and with TT set up - so tolerance please if I'm way off base/out of order here.
I too am just installing a new TT set up ~10-12 ft remote from my integrated amp/receiver/theatre suite.
My integrated also does not have balanced inputs, only RCA but my phono prestage does have xlr out, along with a volume/gain control output.
I have a relative that is a producer/record label owner dealing with proaudio recording and editing suites of his material/artists in his studios. He's suggested to use a 2ch balanced/unbalanced converter box installed next to the integrated and run balanced the 12ft from my phono stage. They do these type of converters for Mic's and other equipment in their studio and at live concerts with much success.
Although I have not sourced a component or DIY for the bal/unbal converter yet, I'm guessing this should work like a charm and be virtually (induced) noise free.
I can report back in a few weeks when I've got it sorted.
Cheers & Good luck.
Dave |
Jimmytrk,
Your post is fully within the topic.
I believe that if one end of a XLR wire is converted to RCA, it behaves as an unbalanced connection. To get the benefits of a balanced connection all components in the chain must be balanced. |
Jimmy, Possibly the converter box you mention contains a transformer, which can effect balanced transmission between your phono and linestages, but I believe the OP was asking about running 24 feet of phono cable, i.e., from the tonearm to the phono stage. The consensus is that this is not advisable, even if one has a fully balanced phono stage, although it is more feasible with balanced lines than with unbalanced ones. |
I think Jensen Transformer make such a device. Have never tried one though. In this case you could put you TT and phono stage were you want and run XLRs to the transformer by the integrated amp. I think it would be worth a try. You may want to ask Allnic if that makes sense to do. |
I have googled and found some conversion boxes that do what you suggest. With one of these boxes I could put turntable and phono pre close to each other, run a long balanced cable to the conversion box and a short RCA cable from the box to the integrated amp.
Problem is:
1- conversion boxes quality seem to be below the quality of my other components (at least if price is a good indicator of quality). I fear to decrease overall sound quality
2- I'm very happy with the sound after having located my equipment in the plane of the speakers and therefore not willing to spend much money in relocating
I must say that I have found amazing the power of collaboration of this group and the number of valid alternatives and opinions I've got! |
Dear J, I may have lost track of the facts, but I thought your main issue was using very long phono cables, from your tt to your Allnic. And then I thought that you have had a good result moving the Allnic (at least) close to your tt so as to obviate the need for long cables. Once you've done that, I also believe the Allnic has balanced output, so you should be "home free", if you want then to run long cables from it to your integrated amp or linestage or whatever. You don' need no stinkin' converter boxes. |
Dear L,
My first question was about feasibility of using long balanced cables to connect my arm to the phono pre. My intention was to separe the TT from the rest of the equipment, as it is the most prominent, disruptive piece within my music rack and was clearly interfering with the back wave of my electrostats. I was asuming that my phono pre had XLR inputs. Through the postings I realized that what it actually has is a XLR output but only RCA inputs (ooops!).
Your suggestion about positioning the rack right between the plane of the speakers worked so well that I considere I have solved my problem.
I cannot separate phono pre and integrated amp without using the conversion box because the amp does not have XLR inputs to match the phono pre XLR output.
I could still move the TT and phono pre away from the rest of the equipment using the conversion box mentioned in latest posting, but I'll skip it as I'm happy with what I have now.
Hope this clarifies. |
I have three turntables in two systems. One of the turntables is off the main gear table in one of the systems and requires a 20' stereo phono cable from the step-up transformer to the phono preamp. Zu Mission cable proved up to the task. It's quiet and the xformer output has no trouble driving the length resulting in uncompromised, full-bodied sound.
*This would not work if the cartridge had to drive its signal through that length of cable* alone, but if you use a MC with a xformer, Zu Mission will likely suffice at 24', however you terminate it. So I suggest a normal length tonearm cable to SUT, then 20 - 24' from SUT to your electronics. If you're using a HOMC or MM cart and expect to drive 24' directly from the cartridge motor, don't.
Phil |
Hi All, Thanks for not flaming me for hijacking....
Admittedly I haven't read in detail all of the posts since mine. I hope I don't run off topic, or step on toes.
To respond/comment:
Jbuenech: Glad your phono cables are working. Mine do too! ;-)
But I've put my phono pre right next to the TT, 12ft from my integrated.
But in answer (from (me) a novice really) XLR Can be converted effectively to unbalanced by use of a audio transformer circuit (like the Jensen units Sarcher30 suggests.) But can also be converted using what I've seen as even higher quality OPamp circuitry - near or at audiophile quality.
Conversely, unbalanced output can also be converted to balanced using the same circuit types. In the case that you'd need to run an unbalanced analog source over a distance to a pre amp. Say Reel to Reel, or similar.
This is essentially what audiophile components offering both balanced and unbalanced connections have built into their internal circuitry providing BOTH types of analog input/output.
Radio and pro audio set ups have been doing this for years!
I too found the pro audio stuff has low quality as far as audiophile. But, I've sourced, by sheer accident & luck something that looks promising: Benchmark Media Systems, inc - Yes those guys with the Highly rated DAC & ADC equipment - make several low noise hi audio quality converter boxes and circuits.
I've just found on e-Bay, used an IFA-8 4 channel Input amplifier. Converting XLR to RCA using very good OpAmp circuitry. I intend to wire it up to bridge fully balanced over the 10-15ft then short 12" RCA unbalanced into my integrated. If these units are still not to the quality I'd prefer, I'm pretty sure I can DIY them with upgraded components on their boards, or have someone do them for me.
Benchmark Specs on the IFA-8:
A quad input amplifier with CMRR = 90 dB to 2 kHz, a +28
dB input clip point, DC offset of 120 dB
dynamic range.
> 200 kHz bandwidth
- THD @ 2 kHz = 0.0008%
- 10 kOhm balanced inputs
Benchmark also offers the raw circuit boards of similar quality (these are what are used in the IFA-8 etc) as well if any of you DIY'ers want to modify the internal inputs or outputs of your components.... (I take no responsibility for your success of failure - you attempt at your own risk.)
For completed converters - Check out IFA-8 Quad Balanced Input Amp, IFA-3 Stereo Balanced Output Amp, IFA-4 2 Ch line amp for ridiculously long runs,) IFA-5 QUAD BALANCED OUTPUT AMPLIFIER, IFA 7 Stereo Headphone Amp
Power is either by PS-11 or PS-1 Power supplies.
For raw XLR to RCA / XLR to RCA IN / OUT conversion circuits - See DIA-1, DIA-2 Input amplifiers, and DOA-1, DOA-2 Output amplifiers.
And... Nope, I in no way work for nor profit from sales of Benchmark products. Got mine on eBay.
But I did call them and spoke to one of their sales managers - very helpful and pleasant fellow - he sold me a PS-1 Pwr supply for $36, and I also bought 2 15ft XLRF/XLRM Cables for my set up. He also advised to put the phono pre next to the TT, run the distance with XLR, then step down with the IFA-8 placed right next to & feeding the integrated... So, I seem to be on the right track.
I'm currently running phono cables over the distance (they actually sound quite good.) As I'm still waiting on parts to arrive, I have not installed my balanced set up yet. So, I cannot yet provide real world/first hand testimony to the audio quality, but the specs look very good to me, and I do expect the balanced set up to sound better, and be much more noise immune as compared to the phono cables.
Cheers All! |
Listening test results!
- Installed qty (2 L+R) Benchmark 15ft XLRM-XLRF cables, 1 Benchmark Media Systems IFA8 & PS-11 pwr supply; 3ft (1m) Cheapo high-end consumer phono cable to integrated/receiver - Yamaha RX-V992. Spkrs Boston A-150 II's.
Analog source: Rega P5 + Rega TTPSU, Rega Exact cart, PS Audio GCPH phono stage.
Listening to the TT playing while switching between the 2 source paths - Balanced 15ft, and phono cables 15ft - I could not noticeably hear a difference in audio/music quality. To my ears, both sounded very comparable & musical. Crisp highs, full mids and great fast and low bass.
With TT turning but the arm in the up position, setting the mains volume to MAX, the noise floor between the 2 paths was very contrasting. The Bal setup appeared to cut the noise floor by full 1/2. As I don't have a scope handy here to measure, I'll settle on my ears test.
I'm sure audio purists may descent opinion, but the BAL/SE input amp I'm using even with consumer grade cabling appears (to my ears) to perform extremely well and much reduces the already low noise of my last config.
So, It works. I'm happy. And my first play of "Let It Bleed" from my new box set remastered copy of the Rolling Stones 1964-1972 - sounds fantastic!!!
If anyone needs to input Bal to unbal / single ended equipment it can be done quite effectively.
Cheers,
Dave |
