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krell ksa5 klone


kevin gilmore

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I actually figured out what the morons did to the cable, and what transistor popped

because of their stupidity before the thing actually showed up. So other than taking

it apart, the repair was easy. And while I was at it, 4 of the blackgate caps in the

power supply were replaced with 35v versions instead of the 25v versions running

at 34V which Mikhail stuffed in there.

 

Pictures later as I take the cable apart.

 

I get to listen this weekend to the real thing vs the klone. Its a rough job, but someone

has to do it ::)

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WARNING to any one that would even think of buying a Revelation Audio Labs power supply

to amplifier cable for a real krell ksa5. These fucking morons can't even wire a simple cable

and get the pins in the right order.

Tom found this out when his ksa5 blew up. So its sitting on my lab bench, and about 3 hours

of repair time to repair the damage. And tom was very lucky, it could have been worse.

Ended up with -21 on the +21 line and vice versa. Without the protection diodes, very

bad things would have happened.

Waiting for tom to give me permission to rip the cable apart and see how bad the assembly

job is. Shades of coconut audio with blobs of modeling clay.

You mean these guys? Not sure I understand paying a whole bunch of money for an umbilical. Audio grade connectors? Uhh, yeah :rolleyes:

 

Glad the damage wasn't worse and that you can fix it for him.

 

I guess an addition will need to be made on the "apology" on the home page:

 

A word from the Owner and President, Brad Vojtech:

 

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Sweet! Almost done collecting parts here....just need a few more and the boards to come in from Lil' Knight and I'm building. :)

What value Pot did you end up using?

I'm going to use Amphenol military PT06A84 as the connectors for the umbilical....but then considered trying Neutrik RJ45 connectors.

http://www.mouser.com/ProductDetail/Neutrik/NE8FDV-Y110/?qs=sGAEpiMZZMvQhAhQbXdbBsdmA6gGtClgIownSYewpEY%3d

Looks like they can handle the load and would be very tidy. Thoughts?

planked the amp out with a Blue Velvet. sounds excellent even with a cheap pot. some noise beyond sane listening levels with the 102dB AD2000 and 103dB D2000, and basically dead silent until the last hour or so on the pot with the 93dB K701, but a rats nest of wiring right now. can't wait to get it in a chassis with a TKD or GP.

if my maths are correct, the gain is 5x?

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You mean these guys? Not sure I understand paying a whole bunch of money for an umbilical. Audio grade connectors? Uhh, yeah ::)

 

 

yes those fucking incompetent morons.

 

After over 30 minutes of attacking it with an xacto knife, this

 

http://gilmore.chem.northwestern.edu/dsc_0510.jpg

 

gardenhose and glue

 

here are 2 more.

http://gilmore.chem.northwestern.edu/dsc_0511.jpg

http://gilmore.chem.northwestern.edu/dsc_0512.jpg

 

2 of the wires are not even fully soldered.

and does anyone really think this is 99.999% pure silver.

 

there is no such thing.

 

This is a $700 cable...

 

but wait, there is even more

http://gilmore.chem.northwestern.edu/dsc_0513.jpg

 

there is white shit leaking out of the hose inside the

connector.  Its talcum powder or some such crap.

probably why they tried to fill the ends of the gardenhose

with industrial strength glue, which since it does not bend

with the cable (like rtv would) ends up cracking and leaking

out the powder.

 

WHAT THE FUCK...  they really must have hired Patrick to make

this crap.

 

speaking of which, his latest website is quite funny.

Edited by kevin gilmore
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OMg, that's crap! $12 connectors filled with goo. What brand/model is stamped on the cable...or is that a "custom" bundle?

yes those fucking incompetent morons.

 

After over 30 minutes of attacking it with an xacto knife, this

 

http://gilmore.chem.northwestern.edu/dsc_0510.jpg

 

gardenhose and glue

 

here are 2 more.

http://gilmore.chem.northwestern.edu/dsc_0511.jpg

http://gilmore.chem.northwestern.edu/dsc_0512.jpg

 

2 of the wires are not even fully soldered.

and does anyone really think this is 99.999% pure silver.

 

there is no such thing.

 

This is a $700 cable...

 

but wait, there is even more

http://gilmore.chem.northwestern.edu/dsc_0513.jpg

 

there is white shit leaking out of the hose inside the

connector.  Its talcum powder or some such crap.

probably why they tried to fill the ends of the gardenhose

with industrial strength glue, which since it does not bend

with the cable (like rtv would) ends up cracking and leaking

out the powder.

 

WHAT THE FUCK...  they really must have hired Patrick to make

this crap.

 

speaking of which, his latest website is quite funny.

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Sweet! Almost done collecting parts here....just need a few more and the boards to come in from Lil' Knight and I'm building. :)

What value Pot did you end up using?

I'm going to use Amphenol military PT06A84 as the connectors for the umbilical....but then considered trying Neutrik RJ45 connectors.

http://www.mouser.com/ProductDetail/Neutrik/NE8FDV-Y110/?qs=sGAEpiMZZMvQhAhQbXdbBsdmA6gGtClgIownSYewpEY%3d

Looks like they can handle the load and would be very tidy. Thoughts?

 

 

if i go with a loop-out, it will be a 25K pot, otherwise 10K if no loop-out.  i'm going to call Parts Connexion to see if they have any TKDs in stock while the 20% sale is on, otherwise i'll just go with a Goldpoint.

 

the Amphenol Econo-Mate are nice, but physically big.  i really like these from JAE Electronics as well - http://jae-connectors.com/en/pdf/2008-96-97-SRCN.pdf .  

 

Par-Metal sent me a a lid with paint drippings.  they're sending me a new lid, but may end up going with a Lansing chassis instead, so no chassis work until i get this sorted.  Par-Metal is another 6 mo. out from doing any anodizing since the fire.

 

i didn't do any BJT matching, but without the opamps installed, i get 16mV and 120mV DC offset.  with the opamps installed, i get 0.6mV and 2.4mV respectively.

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All three of those I had not considered, thanks! The Lemos I had completely forgotten about and are very cool. What caught my attention on using cat6 is it's available in 22awg and good to 250Mhz. Using the whole cable, much like the DB9 Krell originally used, I've convinced myself it will work well and look good.....until of course my kids plug the computer network into it. :(

Still not sure I'll do it though, there's something special about the mil spec connectors.

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yes those fucking incompetent morons.

 

After over 30 minutes of attacking it with an xacto knife, this

 

http://gilmore.chem.northwestern.edu/dsc_0510.jpg

 

gardenhose and glue

 

here are 2 more.

http://gilmore.chem.northwestern.edu/dsc_0511.jpg

http://gilmore.chem.northwestern.edu/dsc_0512.jpg

 

2 of the wires are not even fully soldered.

and does anyone really think this is 99.999% pure silver.

 

there is no such thing.

 

This is a $700 cable...

 

but wait, there is even more

http://gilmore.chem.northwestern.edu/dsc_0513.jpg

 

there is white shit leaking out of the hose inside the

connector.  Its talcum powder or some such crap.

probably why they tried to fill the ends of the gardenhose

with industrial strength glue, which since it does not bend

with the cable (like rtv would) ends up cracking and leaking

out the powder.

 

WHAT THE FUCK...  they really must have hired Patrick to make

this crap.

 

speaking of which, his latest website is quite funny.

Every time i visit head-case, i see brands i previously admired ripped apart. Alo,RSA,Cavalli etc. Stupidity and gullibility due to good marketing does cost money. Reading reviews of people talking about how the cable revealed another layer of the music their previously 5000 dollar cable could not open makes me go =___=. Now, im very apprehensive about buying something even if it sounds good. And there is only one innerfidelity.com

I think there should be a thread where makes of audio products whose items have been thoroughly ripped apart, photographed and have been checked by trusted members should be listed. Purely based on the schematics and build quality. I understand there could be advert and possibly self interest threat but i dont see any way around for us non-tech newbies to do some serious research. I saw the internals of the Alo Studio Six and Woo Wes and my only comment was...they look pretty... and almost got one prior to this forum.

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the original krell db9 cable is wired with stranded 22 gauge spc wire. one wire for each power

supply and 3 for ground. correctly soldered and heatshrink on the pins.

the morons wired all 9 pins with 24 gauge wire. with something higher in resistance.

and at 400ma that makes a defference!

monsterslayer sells pure silver wire at rational prices. even 9 wires 22 gauge total length

of 18 feet is less than $30. so maybe $75 to make a better cable plus an hour of labor.

my guess is that tom is going to get a replacement stax mafia cable that performs correctly

and is way better built. minus the magic pixie dust.

real cryo treatment a no cost option. 77K. now if tom wants 4.2K that is going to be expensive.

Edited by kevin gilmore
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I've always been meaning to buy a pound or so of 925 sterling silver wire to make some cables.  You know me... I buy in bulk!!!  :) 

 

We so have to cryo some headphones one of these days.  Take a SR-009 down to 4.2K and see if it changes anything.  I do wonder how peek will behave after doing that... 

 

Every time i visit head-case, i see brands i previously admired ripped apart. Alo,RSA,Cavalli etc. Stupidity and gullibility due to good marketing does cost money. Reading reviews of people talking about how the cable revealed another layer of the music their previously 5000 dollar cable could not open makes me go =___=. Now, im very apprehensive about buying something even if it sounds good. And there is only one innerfidelity.com

I think there should be a thread where makes of audio products whose items have been thoroughly ripped apart, photographed and have been checked by trusted members should be listed. Purely based on the schematics and build quality. I understand there could be advert and possibly self interest threat but i dont see any way around for us non-tech newbies to do some serious research. I saw the internals of the Alo Studio Six and Woo Wes and my only comment was...they look pretty... and almost got one prior to this forum.

 

A specific thread about ripping shit apart and analyzing it would be fun.  Cables are extra fun too as it is all BS.  Virtual Dynamics was my favorite, garden hose filled with ferrite powder and bog standard inwall wiring (solid core). 

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The connectors on this RAL cable are anything but audiophile grade. The cheapest of

the cheap, plastic insides. I did fix the cable but the thin silver has a resistance of

.250 ohms on each wire, double that of the original cable.

 

amphenol part numbers 

L77DE09S

L717DE09P

 

printed right on the shell.

http://gilmore.chem.northwestern.edu/dsc_0514.jpg

 

this is what they should be using which has machined pins

and high temp polyester instead of the super cheapass thermoplastic

http://www.newark.com/itt-cannon/demm9p/connector-d-sub-plug-9pos/dp/37P0488?in_merch=Popular%20D-Subminiatures

 

and none of this .925 stuff. we need the real thing

http://gilmore.chem.northwestern.edu/silverbar.jpg

 

this is the powder

http://www.shop3m.com/3m-ceramic-microspheres-white-grade-w-610-1-gal-sample.html

Edited by kevin gilmore
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  • 2 weeks later...

swapped out the RK27 for a TKD 2CP-2511.  preferred the Alps with my Belden screened ICs but coming around to the TKD with some Mogami ICs.  just need to finalize the FPE design.  here's a badge i'm tweaking at the moment.  haven't decided on button-heads or socket-heads.  hole is for an illuminated latching Bulgin switch.

 

http://i23.photobucket.com/albums/b353/fishski13/krellbadge1_zps176452fb.jpg

 

 

amp board standoffs are 3/8 and the PS board 1/4 to allow easy routing/securing of wires a distance away from the bottom of the PCB.  very,very quiet even with the sensitive AD2000 up to 4-5 o'clock.  i bet an encapsulated TX would get you a few dB or of noise attenuation, but any noise is still 6hrs or so past sane volume levels and a 2Vrms source.  dead silent with both the K701 and T50RP throughout full volume sweep.  

 

http://i23.photobucket.com/albums/b353/fishski13/012_zpsdfd46a29.jpg

Edited by fishski13
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Nice! How is your circuit ground tied to chassis ground...looks like you have an RC network there?

swapped out the RK27 for a TKD 2CP-2511.  preferred the Alps with my Belden screened ICs but coming around to the TKD with some Mogami ICs.  just need to finalize the FPE design.  here's a badge i'm tweaking at the moment.  haven't decided on button-heads or socket-heads.  hole is for an illuminated latching Bulgin switch.

 

http://i23.photobucket.com/albums/b353/fishski13/krellbadge1_zps176452fb.jpg

 

 

amp board standoffs are 3/8 and the PS board 1/4 to allow easy routing/securing of wires a distance away from the bottom of the PCB.  very,very quiet even with the sensitive AD2000 up to 4-5 o'clock.  i bet an encapsulated TX would get you a few dB or of noise attenuation, but any noise is still 6hrs or so past sane volume levels and a 2Vrms source.  dead silent with both the K701 and T50RP throughout full volume sweep.  

 

http://i23.photobucket.com/albums/b353/fishski13/012_zpsdfd46a29.jpg

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