advertisement


MDAC First Listen (part XXVI)

Status
Not open for further replies.
The only area where the MDAC2's "Original" headphone amplifier would have be less then optimal would have been into very low impedance loads where beyond about 100mA the output stage would drop out of Pure ClassA operation into ClassB.

This would never be be an issue with normal use - but very low impedance headphones current requirments could exceed 100mA - such as the HiFi Man ribbon headphones which really need a small power amplifier.

The idea is to design a "sliding class A circuit" where the heat dissipation can be kept under control - but if current is required beyond 100mA the circuit would insure the output stage remains in classA operation...

I'm also going to try using a MOSFET output stage... so ClassA Mosfet design...
 
PhilCTTE said:
Verdicts still out in regards and headphones. I get irritable after an hours listening. A weeks delay is well worth it, so a vote for the extra week or so form me.
Click to expand...

I'm not a headphone user - I cannot live with their "sound stage"....

But I'm aware that many are - its why I asked...
 
Hi John,

Headphones important to me, but I connect HiFiMan HE-500 directly to the XLR outputs via adapter cable, so I could continue to do that.

A proper balanced female 4-pin XLR headphone output would enable me to do away with the adapter cable though ...

Regards,

George
 
Hello John and the MDAC community,

I've added me to the MDAC2 list and sent the first payment.

JohnW said:
Question:-

For MDAC2 how important is the headphone output? - should I devote a little effort to making it a substitute for an ultra high end headphone amp?
Click to expand...
For me, it's important especially if the improvement would be benefit for high impedance headphones (HD800).

Merci et bonne chance for this exciting project !
 
JohnW said:
For MDAC2 how important is the headphone output? - should I devote a little effort to making it a substitute for an ultra high end headphone amp?
Click to expand...
A week or two spent is worth while, but may I suggest, that the relays involved shall not be "sticky" kind ;)
 
Hi John,

Making the MDAC2 an even better headphone amp as it already is, sounds really good - I'm very much in favour of it! (Especially against the backdrop of investing only one or two further weeks to reach that stage...)

Regards
Malyq
 
Sorry John I am currently in hospital and only have limited access to the net I wanth to procede with the new board not bothered about headphhone out and the full upgrade
Doyou have my paypal adress if not where should I send it
Geoff
 
GWM said:
Sorry John I am currently in hospital and only have limited access to the net I wanth to procede with the new board not bothered about headphhone out and the full upgrade
Doyou have my paypal adress if not where should I send it
Geoff
Click to expand...

Geoff,

Gosh, sorry to hear your in Hospital - Please don't worry about such matters and get well soon - it goes without saying your MDAC2 position is reserved :)

Best wishes to a speedy recovery :)
 
Malyq said:
Hi John,

Making the MDAC2 an even better headphone amp as it already is, sounds really good - I'm very much in favour of it! (Especially against the backdrop of investing only one or two further weeks to reach that stage...)

Regards
Malyq
Click to expand...

Malyq,

I've been told by many that the headphone output is even better on the Fusion'ed MDAC - your unit is in the next batch so looking forward to your feedback :)
 
JohnW said:
I'm not a headphone user - I cannot live with their "sound stage"....

But I'm aware that many are - its why I asked...
Click to expand...

Perhaps when I try them with the MDAC2 my view will change.;)

Just taken a punt on pair of Audiolab 8200mb mono blocks, as I know it will be a year away before the Mamps.
 
JohnW said:
Malyq,

I've been told by many that the headphone output is even better on the Fusion'ed MDAC - your unit is in the next batch so looking forward to your feedback :)
Click to expand...

Most of the issues I had when using my recabled/balanced K702 disappeared over some weeks of using the MDAC with a different kind of headphones, could the initial "run-in" / "burn-in" take that long? My first listen to the upgraded MDAC was after good 5-6 hours of playback - perhaps it wasn't enough.
Needless to say, the recabled AKG K702 are not really forgiving when it comes to bad/mediocre/decent recordings, which I have lots of - it takes quite a lot of effort to fill the L-R "range" so that it sounds like a room with musicians. The lack of reflections and the extent of instrument separation really got me there. However that's a good thing when it comes to a DAC, right?

I borrowed older Sennheiser HD600 headphones from a friend and the sound is indeed more "pleasant", so I guess it was just me having headphone problems with the upgraded MDAC. :)
Sorry for the false alarm.

edit: err, I meant - upgraded MDAC units in general, I have Toy, not Fusion :)
 
Status
Not open for further replies.


advertisement


Back
Top