24 feet DIN to XLR phono cable for Graham Phantom?

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