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New Preamplifier ugrade

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Preamplifier upgrade.

The new power supplies in the Klein II DAC definitely picked the sound quality up a few notches so I thought I should implement it into the preamp as well. Also the level control using the motorised pot was not optimal so I have switched to full digital control. This works way better with very smooth progressive control & excellent low level precision. Mute is also instant vs the motorised pot which just very slowly went down. The Muse 72320 chip is totally noise free in operation with no discernible level steps or clicks. As there is now no volume knob so a display has been added to show volume level, input & mute. An owner in the USA suggested a gain switch might be handy on the new revised model so I have included this.

Gain - after a lot of R&D in this area I finished up with just a little over 1x. Most DAC’s CDP’s output of 2 v rms on a 0 dB signal which is perfect to drive most power amps, a line level preamp does not need much gain. The rear gain switch doubles this to 2x (+6 dB) so that gives you lot of flexibility. I am more than happy to customise the output levels to suit individual requirements. The output stage runs on plus & minus 15 v rails so fairly high output levels are no problem.

Bandwidth – there are no output capacitors, all sections being DC coupled so this baby runs from DC to 100k+ with an extremely flat response. When I get time I will update the website with full technical specs. Noise levels are very low too so it should be fine with high efficiency speakers.

Summing up – the differences between the original & revised are

Major upgrade to the power supplies – higher output stage voltage & extra Gyrator noise filtering on all audio circuits.

Improved & shorter signal line paths.

Full digital volume control allowing very smooth & precise control.

LCD display showing input, level & muting.

There has been a small increase in cost due to the longer build time & extra parts - cost is now $1000 which includes delivery Australia wide.

 

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If anyone is sick and tied of using typical expensive mechanical volume pots, this is the ticket you're looking for, I'm using the BB PGA 2310 on a commercial preamp @ $6k. Love or hate this some of the high profile brands are taking this concept on. No wear and tear, perfect channel balance, and consistant SQ for the life of the unit! When you sit in the sweet spot the channels come in dead centre, no volume variation and it's accurate to within 0.5d, try getting that out of typical mechanical volume pot, no matter what price you pay! At a $k, it's a bargain, especially to sample the new Muse chip.

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joz   

Looks very schmik.

 

Well done Clay.

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StevenZ   

I'm looking forward to receiving mine.  Should be here by end of the week, I hope.  Will report back when it arrives and thankfully my unit is fully burned in according to Clay.  Excited is an understatement.  Hahah!

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StevenZ   

Alright, now to report on the stuff you've all been waiting for.  My preamp arrived early last week and even though Clay said my preamp had been run in for a bit, I decided to put another 150hrs on it before I did any real critical listening.  This weekend I had a bit of time to sit down and what I heard was just ridiculous.  I'm thrilled to announce that Clay has hit this one WAY out of the park.  By removing the actual potentiometer he's gone to a remote only control which is smooth as butter in operation with no audible clicks or clacks throughout it's range.  Couple this with the adjustable gain setting that he's now including on the rear of the pre and you have a VERY versatile preamplifier that should mate well with virtually any power amp.  

 

The new display is also pretty awesome and with the option to turn it "off" you'll be happy to listen in low light settings and not be hindered by any bright lights.  That's not to say the display is bright at all or intruding in the least, it's not.  I usually listen in near pitch black with my eyes closed and if any component has one of those flash light LEDs on the front panel I find it hard to concentrate.  This pre with the display on is just fine for me and lets me just drift away into audio nirvana.

 

If you guys are on the fence, fear not, this thing is awesome.  I'm using this preamp with a Benchmark AHB2 amplifier which is known for it's downright honest presentation and virtually zero noise floor.  I don't feel that the preamp adds any of it's own flavor to the signal and keeps the noise floor at such low levels that I'd describe the background as inky black.  This allows for incredible instrument separation and air between sounds in the recording with no smearing or overhang.  Everything stays right in it's appropriate soundstage placement with no drift.  Depth is also quite good, extending far beyond my speakers and also well into the room.  

 

This preamp fits right in with what I consider to be a world class amplifier so that said I can't recommend it high enough.  Not only is it a stellar product but you also have the full support of Clay which is invaluable these days when it seems like most companies only see you as a paycheck.  Clay is able to custom tailor the gain settings of the preamp to match whatever amplifier you'll be using with it and I feel that seemingly small customization is just the cherry on top in Clay's devotion to his customers and their satisfaction with his products.  Buy this preamp if you need one. Hell, even if you don't need one, you need this preamp in your life.  Bravo, Clay. Job well done!

 

Sincerely,

Steven Z.

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woadl   

Thanks for that fantastic review Steven it looks like Clay has come up with something quite special

I'm looking forward to the combined DAC/Preamp for my system, my spies tell me it's very close

Edited by woadl

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StevenZ   

Thanks for that fantastic review Steven it looks like Clay has come up with something quite special

I'm looking forward to the combined DAC/Preamp for my system, my spies tell me it's very close

Boy oh boy you are going to be in for a real treat! What amplifier will you be using?

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woadl   

Boy oh boy you are going to be in for a real treat! What amplifier will you be using?

Hi Steve I have the Quad Eighty valve mono blocks driving the ML2 ref speakers

At the moment I don't have a DAC and I'm using a vintage Mark Levinsom JC-2 pre amp

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Jonny   

Alright, now to report on the stuff you've all been waiting for.  My preamp arrived early last week and even though Clay said my preamp had been run in for a bit, I decided to put another 150hrs on it before I did any real critical listening.  This weekend I had a bit of time to sit down and what I heard was just ridiculous.  I'm thrilled to announce that Clay has hit this one WAY out of the park.  By removing the actual potentiometer he's gone to a remote only control which is smooth as butter in operation with no audible clicks or clacks throughout it's range.  Couple this with the adjustable gain setting that he's now including on the rear of the pre and you have a VERY versatile preamplifier that should mate well with virtually any power amp.  

 

The new display is also pretty awesome and with the option to turn it "off" you'll be happy to listen in low light settings and not be hindered by any bright lights.  That's not to say the display is bright at all or intruding in the least, it's not.  I usually listen in near pitch black with my eyes closed and if any component has one of those flash light LEDs on the front panel I find it hard to concentrate.  This pre with the display on is just fine for me and lets me just drift away into audio nirvana.

 

If you guys are on the fence, fear not, this thing is awesome.  I'm using this preamp with a Benchmark AHB2 amplifier which is known for it's downright honest presentation and virtually zero noise floor.  I don't feel that the preamp adds any of it's own flavor to the signal and keeps the noise floor at such low levels that I'd describe the background as inky black.  This allows for incredible instrument separation and air between sounds in the recording with no smearing or overhang.  Everything stays right in it's appropriate soundstage placement with no drift.  Depth is also quite good, extending far beyond my speakers and also well into the room.  

 

This preamp fits right in with what I consider to be a world class amplifier so that said I can't recommend it high enough.  Not only is it a stellar product but you also have the full support of Clay which is invaluable these days when it seems like most companies only see you as a paycheck.  Clay is able to custom tailor the gain settings of the preamp to match whatever amplifier you'll be using with it and I feel that seemingly small customization is just the cherry on top in Clay's devotion to his customers and their satisfaction with his products.  Buy this preamp if you need one. Hell, even if you don't need one, you need this preamp in your life.  Bravo, Clay. Job well done!

 

Sincerely,

Steven Z.

 

 

I agree! great post and it's spot on. I got the preamp today and I'm using it with the Klein II. It sounds astonishingly good! great work Clay. 

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Can the low noise PSU be used with the new pre?

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No - The preamp is powered by a external transformer - 9v AC. It already has multiple internal low noise power supplies.

 

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bhobba   
Posted (edited)

Hi Clay

 

Great to hear mate.

 

My friend Kev who has the ML5 references or whatever he want's to call them on order form Mike, and who you saw at Mikes last Monday may want one depending on the way he want to go with amps.

 

I think he may like mix and match.

 

For stuff with real 'ooomph' he has the Arion 500's - for less 'loud' stuff he might like my heavily upgraded Leak you worked on - its sounding even better now.

 

BTW Clay has my Truth pre to repair a simple fault - his pre easily bests that - but admittedly its higher priced.

 

Thanks

Bill

Edited by bhobba

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