System #382 (reQuest)

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rdnzl999

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Mar 6, 2011
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Location
Riverview, Florida
1. Member Name: Jimbo

2. Location: Near Tampa, Florida

3. ML Model(s): reQuest


Currently gainfully de-employed.


Main Room:
ReQuest - black - bought in 1998
Acurus A250 - 1996
Benchmark DAC1-HDR as preamp - 2010
Sony XDR-F1HD Radio tuner analog out - 2010
Phillips DVD player as Coaxial Digital Transport - set to upsample CD - 2005
LG 50" PK950 Plasma TV - optical out - 2010
i7 PC optical outset to 192khz/24bit - 2008

Placement: 44" from front wall, 25" from sidewalls


2011-03-07_0833.png


Bedroom:
SL3 - Oak - 1996
Pioneer FM Receiver 45w- 1973
Sanyo LCD TV - inherited

Cables:
Analog Interconnect - awg24 solid core coax
Speaker - heavy awg10(?) solid core coax, biwire, with parallel awg24 solid core coax on the panels. Also have Kimber 8TC on loan from a friend with CLSa, and lots of old cable experiments
Digital RCA - anything that conducts the signal
Plain HDMI
Ferrite chokes on all analog cables

Music:
Carla Bley, Stravinsky, Steely Dan, Zappa, Hermeto Pascoal, Beatles, Who, Joni Mitchell, Jethro Tull, Bartok, Hindemith, Kazumi Watanabe, Monk, Bela Fleck, Bach, etc. Often prefer "live" recordings. Lots of downloads from www.DimeaDozen.org

Modifications:

The analog cables are all single core coaxial pairs, with ferrite chokes on cables and power cords.

Ferrite stops stray RF from entering the input or affecting output feedback into the gain stages on output cables. The idea being to prevent the amp from trying to amplify or correct for RF. I had so many of them available they are liberally applied to all the power cables too.

Acurus has had the internal 6amp fast-blow fuses replaced with fire-hazard copper jumpers. I could see a voltage drop across the fuses (4, one on each lead from the filter capacitors). Also, small RF caps soldered across the filter caps to shunt the RF noise from the rectifier.

Lust:
Probably getting an old KAV-250a soon. Some FPB-600 lust too, though a little afraid of the complexity in that beast.
 
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Acurus has had the internal 6amp fast-blow fuses replaced with fire-hazard copper jumpers. I could see a voltage drop across the fuses (4, one on each lead from the filter capacitors).
Welcome aboard. Nice system, but not a good idea replacing fuses with copper jumpers. If there's a fire your insurance will be void. Did you hear a difference when you replaced the fuses?

BTW you stated "Digital RCA - anything that conducts the signal". I have found that there IS a difference between digital cables.
 
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Fuses and Digital Cables

Welcome aboard. Nice system, but not a good idea replacing fuses with copper jumpers. If there's a fire your insurance will be void. Did you hear a difference when you replaced the fuses?

Don't try this at home! No user servicable parts inside!

That's a good point. It still has a fuse on the AC main (which I reduced in size and changed to fast blow sized according to testing -- when the power turn-on inrush current no longer blew it, it was juuuust big enough, and smaller than the original).

I'll testify that I heard a difference at the trial.

Looking at the web... from PSAudio... "High end replacement fuses for equipment that make a noticeable sonic improvement. While small in physical size these are, as their name implies, Critical Links in the AV chain. Consider that all the AC power in your equipment must pass through these tiny bottlenecks called fuses. Once placed in your equipment, dynamics improve, transients sound quicker with greater energy and inter-note separation improves as well. Critical Link Fuses are easy to install and make a world of difference. "

Yep, that's what I heard 12 years ago. Cleaned things up.

On the other hand, I don't play things so loudly in this house, so might re-fuse it. Solder the fuse in and forget about it.

BTW you stated "Digital RCA - anything that conducts the signal". I have found that there IS a difference between digital cables.

Could be, could also be DAC dependent -- input buffer, method of clock regeneration, etc.

I tested with a "passive preamp" -- rca cables with an attenuator -- to vary the signal level -- the result was that the music was either on or off, there was no "degraded" state that I could detect visually (error indication on the DAC) or audibly, so, at least for the time being, not concerned.

"The DAC1 HDR employs --blah--blah--blah-- Specified performance is consistent and repeatable in any installation with cables of any quality level."
http://www.benchmarkmedia.com/sites/default/files/documents/DAC1 HDR Manual RevD.pdf

If a fancy cable comes my my way I'll put it in, no harm there.

I'm new to having an outboard DAC. I don't hear a "difference" among any of the digital souces (coax and optical) attributable to the varying cables.

And optical input, same deal -- I get the cable to within about 1/2" (like I am going to plug it in) of the detector in the input to the DAC and it starts playing without errors.

Maybe yours makes a difference.

I do agree with analog cables making differences. The zip-cord went in the trash a long time ago.
 
Lusts fulfilled...

Replaced the Acurus with a Krell KAV-250 and a week later with Krell FPB 350 Mcx.

Replaced the Phillips DVD with an Oppo 93.

Added a Roku.

Replaced the rack with a steel/glass AV stand.

2011-08-11_0435.png


Cable Universal Remote works with the amplifiers.


2011-08-11_0448.png


I feel like I'm done for a while, except the place is still a bit of a mess.

---

All six DAC1 inputs are filled...
Analog - Sony HD Radio
USB - PC
Optical - TV (sometimes to PC)
Coaxial - Cable box, Oppo, and CD Player

Analog out - balanced (XLR) to the amps.
 
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Speaker Wire Change (DIY)

As probably noted above, I've become partial to single-solid core wiring for signals and speakers.

A friend bought and liked Mapleshade's cables, so it sent me on an investigation.

http://shop.mapleshadestore.com/Cleaview-Golden-Helix-Speaker-Cable-with-iPLUS_i-upgrade/productinfo/HELIX-PLUS/

Another vendor : http://www.anticables.com/




After listening and looking at the physical cable, I mumbled "this is magnet wire".

It's always colloquially referred to as "Enameled" wire, but there are various specifications.

I bought a roll of this in 18awg: http://www.amazon.com/Magnet-Enameled-Copper-0-0418-Diameter/dp/B000IJW81C/ref=sr_1_1?ie=UTF8&qid=1318560858&sr=8-1

NEMA MW 80-C and MW 80-A
Class 155 - Copper - Round Conductors - Polyurethane/Polyamide coated magnet wire/winding wire.

The copper is likely grade "Electronic Tough Pitch" so it doesn't have the highest purity, nor does it have the silver plating of the Mapleshades.

This product sheet is likely very similar to the wire I bought -- see pages 8 and 9 -- http://www.reawire.com/LinkClick.aspx?fileticket=efryCHndEnI%3D&tabid=64&language=en-US

I like them.

Wires after twisting into pairs, before trimming and exposing the ends.
MagnetWire_Cables.jpg

At the left speaker:
MagnetWire_at_Amp.jpg

At the left amp. Old cables (yellow) gathering dust.
MagnetWire_at_Speaker.jpg
 
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