[Stanfoo]

Would you suggest the NFB-11 or NFB-15 to pair with the HD598?

 

[willowbrook]

Yes, the mute relay problem has been fixed with a switch to disable it.
NFB-11 or NFB-15 might be an overkill for HD598, but I can suspect that NFB-11 will sound very good with it. You can always upgrade headphones later to maybe HD600/650, so it's never a bad investment
I always found E17 to be a good match with the HD598, so I never bothered getting a better DAC/amp until I decided to buy HD650 and DT880.

 

[Stanfoo]

Thanks. I too am currently using the E17 with my 598. But I'm looking to upgrade to the NFB-11/15 for better SQ.
 
Just worried if going the NFB-11 route would lose out on noticeable warmth, since the E17 is warm.

 

[willowbrook]

The HD598+E17 was noticeably warm and I am guessing that you will lose some of that warmness when you switch to NFB-11. The NFB-11 isn't all that neutral/dry, it is a tad bit on the warm side (the amp). I doubt you would notice considerable improvement of SQ of HD598, but I have never heard HD598 with NFB-11, so I cannot give you a definite answer.
The NFB-11 is really a worthwhile equipment to invest in and you won't be disappointed, especially with the new switch for the relay fix.

 

[SpirosG]

NFB-11 was pairing in a fantastic way with my older HD-595, which is exactly the same can as 598 ... 

 

[acbred]

Could anyone please explain why the custom option page says "There are two TCXO can for upgrade. Cost is USD20 per..." Is it possible to only upgrade 1 out of the 2? Would that even make sense?
 
I would email them to ask but I was hoping to try here first if someone who speaks English well could try and explain. Thanks.

 

[robbo0]

I opted for the upgrade and they put the quota in for x2 (40USD). I don't know the specifics to audio engineering, but I would have thought you'd want standardisation across units to ensure quality, proper function - especially with audio as there's more likely to be an audible difference in the result I would have thought.  My logical metaphor would be - Like having one wheel go faster than the other on a car. But it may be that whatever this specific audio component is that you can get away with one and still get something out of it  I'm sure someone here will know the proper in's and out's and be able to tell you.
 
EDIT: That said it seems odd that they'd put 1 TCXO as 20 USD instead of just stating upgrade: 40USD TCXO x2 if you couldn't have just one upgraded. 

 

[Stanfoo]

I have no idea what TCXO is. Can you briefly explain it and the purpose of the upgrade?

 

[acbred]

Yea it just doesn't make sense to me but I don't know even know what a TCXO is either. Unless someone provides an explanation of what it is and how it makes sense to have either 1 or 2 I'll shoot audio gd an email to try and get an answer.

 

[mandrake50]

  Yea it just doesn't make sense to me but I don't know even know what a TCXO is either. Unless someone provides an explanation of what it is and how it makes sense to have either 1 or 2 I'll shoot audio gd an email to try and get an answer.

"A TCXO is a temperature compensated crystal oscillator. Compensation components have been added to enhance the temperature stability of the basic oscillator to improve performance in more critical applications."
 
It is the clock for the DAC... higher precision than the stock one I presume. You would want one for each DAC chip  ... in a maxed out design.(I see that in the NFB 11 they are offering one for the USB chip")
To reduce jitter. Some say it makes an audible difference, some say it does not... I guess the next step up is the FEMTO clock used in some higher end digital equipment.
 
I see what they are doing... offering one for the DAC and one for the USB chip... I would think one would go for the DAC clock first.... in asynch, it is reclocking everything... then USB... if you just want all of the bells and whistles.. and don't mind spending the $40

 

[Surlias]

Who knows, could be total placebo. I hate skimping though, so I went ahead and got them. I know it would have bothered me not to have upgraded them, knowing that there was a potentially "better" version of the device I bought. Silly but psychologically significant in my case.

 

[willowbrook]

  Who knows, could be total placebo. I hate skimping though, so I went ahead and got them. I know it would have bothered me not to have upgraded them, knowing that there was a potentially "better" version of the device I bought. Silly but psychologically significant in my case.

Exactly the reason why I also got them

 

[mandrake50]

  Exactly the reason why I also got them

I got neither the upgraded clocks nor the bigger transformer (which is now standard I think). I am quite happy with the unit that I have though..
They say ignorance is bliss...

 
Of course I may have sprung for the upgrades had I seen that they were available. Somehow I missed that whole section on upgrades when I ordered mine.
 
I would love to hear about it if anyone has had the chance to listen to a unit with and one without the upgrades. Impressions would be quite interesting.

 

[robbo0]

 
I got neither the upgraded clocks nor the bigger transformer (which is now standard I think). I am quite happy with the unit that I have though..
They say ignorance is bliss...

 
Of course I may have sprung for the upgrades had I seen that they were available. Somehow I missed that whole section on upgrades when I ordered mine.
 
I would love to hear about it if anyone has had the chance to listen to a unit with and one without the upgrades. Impressions would be quite interesting.

 
I've got the upgraded transformer and TCXOs for the NFB-11 arriving soon, but cannot say personally what the differences are as I've not heard the original.
However according to their site the differences are:

 1, Transformer upgrade, from 20W to 35W, which is improve on  the drive ability and the sound quality richer.

 2, Upgrade TCXO for USB chip and ES9018.
     There are two TCXO can for upgrade,  Cost is USD20 / per without shipping delay .This upgrade only can slightly improve on the sound transparency .

 

[Stanfoo]

What did you guys choose for the declare value of the item? By default they declare it at $80 but they allow you to change this.