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The John Westlake/Lakewest MDAC/FDAC, VFET and Detox

JohnW said:
Clive,

Yes the same level into balanced headphones upto 0dB volume setting, but not the MDAC's +3dB overrange...

Whats the Max level do you listen to your Sennheiser HD800S headphones at?
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Hi John

Just been listening to Mahler's 2nd Symphony (Simon Rattle, City of Birmingham Symphony Orchestra, EMI 1987) at 0dB. This CD hits 0dB (analyzing the .wav suggests that the peaks are perhaps 6dB or so compressed) and yet many passages are so quiet that the MDAC level indicator doesn't even flicker. Occasionally I have turned up to +3dB to really listen to the quiet bits!
 
Arh - the good old days of recordings with Dynamic range - really not for late night listening...!

The DevDAC (We need a better name) will sound far better then MDAC, but max level is only 0dB....
 
JohnW said:
Arh - the good old days of recordings with Dynamic range - really not for late night listening...!

The DevDAC (We need a better name) will sound far better then MDAC, but max level is only 0dB....
Click to expand...

In the evenings I have to go into the conservatory, close the doors into the house and listen via my DAP. It has 3.6v available on its 2.5mm balanced output and I have to listen to the above with volume at 100%.
 
JohnW said:
Whats the Max level do you listen to your Sennheiser HD800S headphones at?
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FYI John, I tend to listen at say-18dB to -8dB on my Pro-Ject S2D with my HD800Ss, and about 2dB quieter with my LCD-3s. I never get the sense that there is any constraint of power.
 
adamdea said:
So. With Christmas coming:-
a) is the PCB design complete? If not what part of the design remains to be completed and when is it likely to be completed? By when does the manufacturer need the completed design in order to meet that date?
b) when can the PCB be manufactured?
c) has the chassis been designed. If not what part of the design remains to be completed and when is it likely to be completed?
d) when can the chassis be manufactured? Has this been firmed up with the manufacturer? by when does the manufacturer need the completed design in order to meet that date?
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I'm hoping you are on John's ignore list seeing as he's been here today and not answered any of your questions. I would ask him but I'm on his ignore list also, nor do I get a great response when emailing him. Still waiting for a response I sent him 8th November.
Can someone else copy and past Adam's questions in to a new post so John can see it and hopefully reply?
 
Mark Dirac said:
FYI John, I tend to listen at say-18dB to -8dB on my Pro-Ject S2D with my HD800Ss, and about 2dB quieter with my LCD-3s. I never get the sense that there is any constraint of power.
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Good to know, the DevDAC II when used with balanced headphones (using the 4W XLR) will have double the output level when compared with the ProJect DAC.
 
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killie99 said:
I'm hoping you are on John's ignore list seeing as he's been here today and not answered any of your questions. I would ask him but I'm on his ignore list also, nor do I get a great response when emailing him. Still waiting for a response I sent him 8th November.
Can someone else copy and past Adam's questions in to a new post so John can see it and hopefully reply?
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Yes please. Or is everyone else happy that this thread shows a new businesslike and quite-clearly-getting-on-with-it attitude at variance with past history such that asking questions about progress is unnecessary and impertinent?
 
I think too many people are frightened to question John Westlake about how he has conducted himself in this fiasco - I can't quite get my head round that.

He has £100k of our money for a project that is 6 years late and seems to care not a jot that his belligerent attitude, sooner or later, is going to piss someone off so much that they will take him to court to recover their money.

For the record, my last email to him on the 8th November was asking about when he thought FDAC would be delivered - 6 months, 12 months, 18 months? I've had no reply despite re-sending him the email and asking for a response. Take from that what you will.
 
adamdea said:
Or is everyone else happy that this thread shows a new businesslike and quite-clearly-getting-on-with-it attitude at variance with past history such that asking questions about progress is unnecessary and impertinent?
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Personally I've given up.
 
I would like to be proven wrong in my fears that this is playing out as usual. Sorry to be a nuisance but would @Tony L be prepared to ask John for update. On 30th October John said he hoped to have a PCB spin issued within 3 weeks.
 
Hey John,

Got some Q’s for you please to keep this thread serving it’s intended purpose. Please see Adam’s quoted text and consider removing him from your ignore list.

adamdea said:
a) is the PCB design complete? If not, what remains
b) when can the PCB be manufactured?
c) has the chassis been designed. If not, what remains?
d) when can the chassis be manufactured? Has this been firmed up with the manufacturer?
Click to expand...
 
Mdac quite regularly gets used at +1 to +2db into Ncore n400s... Pretty insensitive speakers.
At times I wish for more, so may need a second preamp between the dac and amp, which somewhat negates the point :/
 
Just an Update on DevDAC timeline, we have a weekend listening session arrange for the last week of January - where we will be comparing the DevDAC against a Chord Dave + the Chord oversampling filter... I understand that the Chord DAC system is rather highend so its going to be an interesting few days!!! I have NO idea how it will compare but good to set the bar high :)

So DevDAC has to be ready for listening by end January...
 
sam_cat said:
Mdac quite regularly gets used at +1 to +2db into Ncore n400s... Pretty insensitive speakers.
At times I wish for more, so may need a second preamp between the dac and amp, which somewhat negates the point :/
Click to expand...

We might be able to push the level a few dB, but we are PSU headroom limited on the DevDAC.... remind me when we build your board to try and increase the 0dB output level for you...
 
sam_cat said:
Mdac quite regularly gets used at +1 to +2db into Ncore n400s... Pretty insensitive speakers.
At times I wish for more, so may need a second preamp between the dac and amp, which somewhat negates the point :/
Click to expand...
Quick google search showed one kit for sale and for it Input sensitivity was 2.05V. A bit unusual.
 
JohnW said:
We might be able to push the level a few dB, but we are PSU headroom limited on the DevDAC.... remind me when we build your board to try and increase the 0dB output level for you...
Click to expand...

Thanks,
Got to do some reading as apparently the gain can be easily modified on these (change a couple of 0603 resistors).. Bumping the gain on the amp a bit feels more sensible. Saves 'custom' on other this.

https://www.diyaudio.com/archive/bl...01-ncore-based-power-amplifier-nc400_04xx.pdf

Discussion on gain :-
https://www.hypex.nl/img/upload/doc/an_wp/AN_Voltage_gain_hypex_modules.pdf
Voltage gain is 26 dB (20x) - its an arbitary choice and easily changed by swapping the value of R141
 
At my age I can’t see most of these new-fangled SM components, LOL. When I were a lad we used RLR05s, and we were grateful for it!
 
JohnW said:
Just an Update on DevDAC timeline, we have a weekend listening session arrange for the last week of January - where we will be comparing the DevDAC against a Chord Dave + the Chord oversampling filter... I understand that the Chord DAC system is rather highend so its going to be an interesting few days!!! I have NO idea how it will compare but good to set the bar high :)

So DevDAC has to be ready for listening by end January...
Click to expand...
Can someone have another go to extract some coherent information as to the state of development.
This is merely a generalised aspiration without any indication of how it is to be achieved. It also doesn't specifically address anything in terms of delivery of the product as opposed to some sort of prototype. It may be inferred that in the space of some 4 weeks the delivery date has gone back by more than 4 weeks. So when is the DevdacII supposed to be delivered now February, March, Munich?

It does not help that it is justified in terms of personal convenience rather than commitment to investors.
 
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