[chirawatf]

Hi Paulo
 
Please get out of your audio nirvana for a while and add some of your after Burn-in review for us.

 
Thanks

 

[hifimanrookie]

Hi Paulo

Please get out of your audio nirvana for a while and add some of your after Burn-in review for us.

Thanks

I will do that in a couple of days...promise

 

[chirawatf]

I've read your review today and I picked up some parts here
 
...that deep bass...didnt think that a humble 5,28w amp could go that low.. Still, a Home Theater receiver with its multi million watts into trillion channels with 4x 1600watts 35cm subwoofers it is not ofcourse..
 
...because of the abundance of power u have to lower the volume to a very low level so ur head dont explode...
 
...treble can be a bit painful...
 
If I were you, I'm not sure I will watch horror movies with PaG and code-X. I'm afraid of heart attack !

 

[davidsh]

  I've read your review today and I picked up some parts here
 
...that deep bass...didnt think that a humble 5,28w amp could go that low.. Still, a Home Theater receiver with its multi million watts into trillion channels with 4x 1600watts 35cm subwoofers it is not ofcourse..
 
...because of the abundance of power u have to lower the volume to a very low level so ur head dont explode...
 
...treble can be a bit painful...
 
If I were you, I'm not sure I will watch horror movies with PaG and code-X. I'm afraid of heart attack !

That's an abundance of gain. Big difference..

 

[hifimanrookie]

A bit oftopic:

A new apreciation thread that a fellow headfi'er started about balanced amping/ headphones/cables etc. etc. To share ur experiences and share ur pics of ur balanced rig

http://www.head-fi.org/t/609155/toxic-cables-impressions-and-discussion-thread/7290#post_10996666

 

[Frihed89]

That's a very nice piece of gear and its build history reflects BC's commitment to customer service. The only thing he won't build is an amp with a tube output stage.
 
I've had very good luck with Blue Circle gear from the time I first bought the CS integrated, back in 2007.  He's built several custom products for me, including an SBH with a preamp and very big capacitor module, a custom tube preamp and a new, better, dedicated preamp to go with the SBH.  I also have a good friend who is a BC dealer (among other things) back in my home state of Massachusetts. He also made me a speaker adapter with variable output impedance that i can use with my SET and PP power amps.   I'm currently considering one of his BC1020-1022 amps with a few bells and whistles.
 
I did wonder where all the caps are: under the output boards?  I also am not sure how this amp is related to the NSL, which has gadzillion outboards and is about 5 x as high as your amp Which has 6 - enough to put out the 5+ Watts of power on your rig.
 
Also did you get a Shallco attenuator for the volume control.  It doesn't look like there's a lot of room left in the chassis, but it's clearly the best volume control I have ever owned.
 
Finally, what are the output impedances on your balanced and 1/4" output jacks?
 
Have fun.

 

[hifimanrookie]

 That's a very nice piece of gear and its build history reflects BC's commitment to customer service. The only thing he won't build is an amp with a tube output stage.
 
I've had very good luck with Blue Circle gear from the time I first bought the CS integrated, back in 2007.  He's built several custom products for me, including an SBH with a preamp and very big capacitor module, a custom tube preamp and a new, better, dedicated preamp to go with the SBH.  I also have a good friend who is a BC dealer (among other things) back in my home state of Massachusetts. He also made me a speaker adapter with variable output impedance that i can use with my SET and PP power amps.   I'm currently considering one of his BC1020-1022 amps with a few bells and whistles.
 
I did wonder where all the caps are: under the output boards?  I also am not sure how this amp is related to the NSL, which has gadzillion outboards and is about 5 x as high as your amp Which has 6 - enough to put out the 5+ Watts of power on your rig.
 
Also did you get a Shallco attenuator for the volume control.  It doesn't look like there's a lot of room left in the chassis, but it's clearly the best volume control I have ever owned.
 
Finally, what are the output impedances on your balanced and 1/4" output jacks?
 
Have fun.

so many questions and they go so deep...
 
some i cant answer..u have to ask Gilbert about it...as this amp was one of the first he did based on this board..and yep its based on the NSL..as can be read on this mail from him to me:
 

 
Paulo
It's shows the DAC and main amp driver boards.  The smaller one towards the left is the input/gain board.  The main driver boards is inditical to one of the NSL output board.  You can say I just steal
one from the NSL production to make your amp.  This kind of custom project is sort of my "pet" project and do it in my "spare" time....... if I can call it spare time.  Production people don't touch it, I do it
all myself.  Ok, may be 95%.  I tell them where to drill those holes.
 
and this:
 

 
See attached
Just passed the bench test this morning.  Max at 5.28 watt ino 50 ohms both channel driven.
 

 
last proof..another mail from gilbert, it was one of the first ones to me after i decided to get an amp to drive a he6:
 
Paulo
I did some digging into the plannar Hifiman headphone.  Were you at one point talking about in the future you may go with a HE6 headphone which require 5 watt into 50ohms to drive it?  I am doing
another customer headphone amp and this customer is using a HE6.  Instead of looking from building a headphone amp point of view, him and I are looking into building a small NSL to drive his HE6.
If you are interested, when I do the prototype for him, I will keep you in mind.
 
 
i showed u this just so no one gets doubts about the work Gilbert does...as i always said it was based on the NSL...
concerning the sound:

check this mail from him:

Regarding the sound of this DAC/headphone amp. It is going to have very large range of dynamic and lot of kick. This headphone amp is going to sound like a NSL but for headphone only. Have you read the two reviews of the NSL? Of course your headphone amp isn't going to able to drive a pair of speaker but it will the similar sound to the NSL.



but i think there is no doubt now my amp is actually based on the NSL..lolz
 
about the other questions....am not technical..so i dont have a clue to answer those my BC friend..maybe u could aks Gilbert, whil referring to this amp..called the PaG...

And no shallco.., he used another premium brand ( Alps lasertrimmed volume control) instead, as it didnt fit

pics didnt work..second try:





ps...u can find the review of my PaG also on the blue circle forum..as i wanted to share my experience with the other BC owners and Gilbert posted very positive about it

ps 2..u say that my amp looks small compared to the full NSL...did u see how huge (hight, depth and weight) )my external powersupply is? and dont forget..its made to drive a headphone only..not full size speakers

its always nice to meet another Bluecircian here on headfi!.

Gadzillion Outboards???? Where? The standard NSL has only inboard components..see this pic:

 

[chirawatf]

Breaking News
CTAG was born!

This morning came the big box from Bluecircle, 44 lbs in weight.
There are 3 tears at the box..(no..o..o..) but Bluecircle's guys wrapped around the CTAG with a very thick foam cushions, giving no chance to be damaged during shipping. No blamish anywhere to the CTAG and it's PSU. Thanks to Bluecircle's guy...Good Job!







I took some photos to share before put them into my audio chain which are

Comp with Sotm PCI usb card-->AQ Carbon USB cable-->Eximus DP1-->Cardas clear light XLR (balance) and Graham copper RCA (unbalance) -->CTAG-->Norse Skuld series headphone cable (balance)+ He6 (hard wired with Norn cable,mini 4pinXLR)
At high gain, balanced input, XLR output...my listening volume was at 9-12 o'clock. So I think CTAG has enough power and reserved to drive my He6.






CTAG Specifications...

Design;
Input Stage: trans-feed forward quasi-mirror semi push-pull differential configuration (Similar circuitry was used in the PAG and also in our $12,000.00 BC307 preamp).
Output Stage: based on the output stage of our $20,000.00 Blue Circle NSL amplifier
Input impedance: BAL is 32 kΩ and SE is 100 kΩ
total capacity ended up being more than 840,000 uF
• Tracking is 0 dB between left/right channels as all resistors in the Shallco attenuator are hand-matched.
• Distortion is < 0.0052% both channels driven into 50 Ω at 2.5 Vrms to 16 Vrms.
• Noise figure is ,< -107 dB (this simply means it is very very quiet)
• Frequency response: +0 dB -0.1 dB 15 Hz to 50 kHz, -0.5 dB @ 175 kHz
• Power supply is fully regulated and incorporates very advanced soft-start circuitry
• Power supply ripple rejection: > 100 dB full power driven into 50 Ω
• Shallco attenuator insertion loss < 0.005 dB
• Into 50 Ω power is 5 W
• Into 16 Ω power is 1.6 W
• Into 32 Ω power is 3.2 W
• Into 300 Ω power is 0.85 W
• Into 600 Ω power is 0.45 W


For the sonic impression, I will share later. Every big amp needs a few hundred hours to perform its best.

 

[Velomane]

Wow, that looks amazing. I'm looking forward to your impressions with the HE-6. Was this a custom job? Tell us a bit about the ordering process and your experience dealing with Gilbert and company.

 

[chirawatf]

Yes, this is a custom job.  At the beginning I email to Gilbert about amp for He6 after that Toby is the man who discuss with me in detail (for example shallco attenuator, the position of input/output).  It took 2 Months to arrive.

 

[conquerator2]

^ How much would that cost, if I may ask? 

 

[gjc11028]

Wow, that looks amazing. I'm looking forward to your impressions with the HE-6. Was this a custom job? Tell us a bit about the ordering process and your experience dealing with Gilbert and company.

I have about five pieces from blue circle, some i bought new, some used which were sent to bc for updates. Everything is made to order, and the product descriptions are treated more like starting points so quite a bit of stuff would be called custom. You can see this if you look at the blue circle forum. I have found him wonderful to deal with -- very flexible and very creative. Thought I would chime in.

 

[gjc11028]

Wow, that looks amazing. I'm looking forward to your impressions with the HE-6. Was this a custom job? Tell us a bit about the ordering process and your experience dealing with Gilbert and company.

I have about five pieces from blue circle, some i bought new, some used which were sent to bc for updates. Everything is made to order, and the product descriptions are treated more like starting points so quite a bit of stuff would be called custom. You can see this if you look at the blue circle forum. I have found him wonderful to deal with -- very flexible and very creative. Thought I would chime in.

 

[gjc11028]

Wow, that looks amazing. I'm looking forward to your impressions with the HE-6. Was this a custom job? Tell us a bit about the ordering process and your experience dealing with Gilbert and company.

I have about five pieces from blue circle, some i bought new, some used which were sent to bc for updates. Everything is made to order, and the product descriptions are treated more like starting points so quite a bit of stuff would be called custom. You can see this if you look at the blue circle forum. I have found him wonderful to deal with -- very flexible and very creative. Thought I would chime in.

 

[chirawatf]

^ How much would that cost, if I may ask? 

Total 3,310 usd (plus 300 usd custom tax)