[Bigload]

I have a new VPI Classic and a Benz Glider SH headed my way and can't wait until it gets here (next week).  Due to my room configuration and component rack limitations, I really need to do a 15ft cable run from the turntable to my AVAStar preamp/phono stage.  The Benz is rated at 2.5mV.  I am using low capacitance LC-1 BJ Cables rated at 12.2pF/ft.  Am I messing up with this long of a cable run? 

[wywires]

Too long, IMO. You're better off placing the phono stage close to the TT and running a long cable to your linestage. Or better yet, Have all your sources and preamp close together and run the long cable from your preamp to the power amp.

[Sonny]

Too long, IMO. You're better off placing the phono stage close to the TT and running a long cable to your linestage. Or better yet, Have all your sources and preamp close together and run the long cable from your preamp to the power amp.

agreed!

[Scottdazzle]

The output from the cartridge is very, very low.  The shorter the interconnect to the preamp, the better.

[wywires]

The output from the cartridge is very, very low.  The shorter the interconnect to the preamp, the better.

Yes, I'd say 2 meters max. Although it's a high output cartridge it's still very very low compared to a line level source.

[Bigload]

I am about as far from being an electronics engineer as one can get!  I do understand the difference between a line level input and the low level signal from a phono cartridge.  But I was hoping the low capacitance of the cables might make it possible to do a longer cable run.  In the end, I will probably have to do a reconfig of my gear, rack, etc., which will be a major, major PIA..... like reversing the whole room and getting the electrician back to redo my dedicated power supplies, redo my acoustic treatments and on and on.  I will do some more serious thinking about how to make it work without having to call in the wrecking crew.  Maybe I can figure something out.  Thanks for your feedback.

[wywires]

I am about as far from being an electronics engineer as one can get!  I do understand the difference between a line level input and the low level signal from a phono cartridge.  But I was hoping the low capacitance of the cables might make it possible to do a longer cable run.  In the end, I will probably have to do a reconfig of my gear, rack, etc., which will be a major, major PIA..... like reversing the whole room and getting the electrician back to redo my dedicated power supplies, redo my acoustic treatments and on and on.  I will do some more serious thinking about how to make it work without having to call in the wrecking crew.  Maybe I can figure something out.  Thanks for your feedback.

15 feet of cable at 12.2pF is 183pF plus the capacitance of the connectors at each end plus the capacitance of the tonearm wire and you're close to 200pF, maybe more. It will work but expect some level of signal degradation. How much? Who knows. I do recall reading somewhere that the RIAA recommends that the total capacitance from the cartridge to the preamplifier must not exceed 220pF. I have no idea how they came up with that number. I still think that shorter is better, especially for phono cables.

[neobop]

This is a HOMC, not a MM cart. Although capacitance will be higher than almost all LO carts, it shouldn't present a problem with the Benz. The problem is really with the length of wire. There's only a few mV of signal. Why don't you give it a try and see what happens.
neo

[Wayner]

The Avastar is a preamp with a built in phono card, so it's not really possible to move the "phono" preamp closer as they are all in one.

The 15 foot length is pushing the envelope a bit as Neo has suggested, and I also like his answer of try it first ass/u/me(ing) that you already have the Bluejeans cables. I've done about 9 feet at once, because of physical limitations.

On another thought, if this doesn't turn out, how about trying a Intelix Audio balun? You need 2 of them, and some CAT-5e wire and you may successfully transmit that distance with little change in the performance. I've often thought of trying this, just to see if it would work out, but never did. Partsexpress sells the baluns, and I'm sure there is a money back deal if it just doesn't work out.

Just a thought.

Or how about a cheap A/D to D/A comversion to get thru the distance thing. Anybody ever try this approach with long distances?

Wayner

[Wayner]

I just got off the phone with Partsexpress and they thought that the balun would work perfectly for the distance.

If you want to go this route, go to www.partsexpress.com

Here is the link for the balun: http://www.parts-express.com/pe/showdetl.cfm?Partnumber=183-600&FTR=183-600

You need 2 of these and some Cat-5e shielded wire.

Wayner

[Bigload]

Thanks Wayner.  I will check it out.  I did try some swapping and rewiring today.  After all of that major swapping, I think I can get the TT close to the preamp but it will be on the top shelf of a 58inch high Sanos Euro rack (wobble-wobble), which is something I was trying to really avoid.  I will definately check this stuff out.  Thanks again.

[Bigload]

I finally have everything here and working great.  The VPI Classic 1 turntable arrived, but it had a Benz Glider S LOW installed instead of a HIGH output from the dealer.  Dealer was helpful and overnighted the correct one to me right away.  So, I did my first cartridge install this morning.....   Tonearm perfectly parallel with the record.  Alignment- stylus precisely in the middle of the white dot and cartridge precisely square and parallel with the grid lines.  VTF set precisely at 1.9 using the enclosed Shure balance guage/scale (my Benz spec range was 1.7 to 2.0).  Azimuth- Used the enclosed silver guide rod laying in the groove on top of the toneam and adjusted the azimuth ring until the guide rod was in alignment with a folded 3x5 lined index card sitting on the record.  Rechecked everything.  Made more adjustments... again and again, until it was all right.   Then I hooked up the 2 baluns and cat 5 cable Wayner suggested for long cable runs.  Great sugggestion and great result.  Then sat back and listened to Jennifer Warne, Pat Matheny, a little Beethoven, Diana Krall, and some Eagles.  Oh my gosh!  This is awesome.  Just can't believe how nice everything sounds and I know it will get better with some break in time.  Thanks for your help and feel free if you have any pointers on the set up process that I might have missed.

[dlaloum]

Glad to hear it all worked out well!

The original documentation for my XLZ7500s (LOMM) specifically states that the low inductance allows for long cable runs...

Most MC's are fine with relatively long runs of decent quality cable.

Most MM's are not (I run the LC1 cable too, but only 75cm of the stuff... keeping the capacitance ultra-low for the MM's)

bye for now

David