MDAC First Listen (part 00100001)

[LarsS]

Of course I agree with all of you on this.
But on the other hand, the common citizen is hardly responsible for political decisions. You may possibly be 'punishing' just another hifi and music lover that happens to live in Russia.

Michael

That may happen ... as coming from Sweden we have a long, long ... long history of wars with Russia.

Initially (1700 - 1800) we usually whipped them but as of the late 1800's they did it to us.

Anyway, Sweden is probably, as small as we are (they envy our democracy, HBTQ rights (maybe not Putin) ), a pain in the ass for Russia.

/Lars

 

[misterdog]

For the record, sadly due to the recent actions at this time I will not accept requests for MDAC2 shipments directly or indirectly to Russia - any payments received will be returned.

While this situation very much saddens me, I feel that its morally important to make a stance against such actions.

Send Mr Putin an MDAC I say, but alter the default screen message from Lake West, to I am A Twat. As the reflection he sees of himself in his mirror seems somewhat skewed.
One of his predecessors incarcerated my stepmother in a labour camp for 15 years for not worshiping him.

Though the more I think about it the bigger the market for such exists.

 

[LarsS]

Send Mr Putin an MDAC I say, but alter the default screen message from Lake West, to I am A Twat. As the reflection he sees of himself in his mirror seems somewhat skewed.
One of his predecessors incarcerated my stepmother in a labour camp for 15 years for not worshiping him.

Though the more I think about it the bigger the market for such exists.

My great grandfather fought the russians 1884 in the north of Sweden, lost his life but won north of Sweden to us.

 

[iansr]

John
Re the MDAC L3/ L4, will it output a digital signal via the BNC connector at the same time as producing an analogue output through the XLRs? I ask because I want to have multiple subs which will be controlled via a DCX 24/96; I therefore want to take a digital output from the MDAC to the DCX.
Also, the digital input on the DCX is an XLR connector, so is it possible to have a cable with a BNC at one end and an XLR at the other or is there an impedance mismatch?
Ian

 

[JohnW]

Ian

The initial software versions will output the digital data "unmodified" so no level control - however on later software builds once we start to perform the Level control with the FPGA we can also offer the option to adjust the SPDIF output level.

 

[JohnW]

One of his predecessors incarcerated my stepmother in a labour camp for 15 years for not worshiping him.

My family and myself are victims of the Soviet occupation of Czechoslovakia - we where persecuted because my Uncle was a famous dissident. My mother was effectively exiled in England - as a result my Childhood was ripped apart, I could speak better Czech then English so my first years at school where not easy.

Its hard to see the potential that history (and the Evil) will repeat itself...

 

[JohnW]

The digital input on the DCX is an XLR connector, so is it possible to have a cable with a BNC at one end and an XLR at the other or is there an impedance mismatch?

No problem, the DCX will work with a suitable RCA to XLR lead - and with the impedance mismatch.

 

[iansr]

Ok thanks John. Once implemented, will the digital output level be controlled by the analogue volume control - so that it is in sync with the analog output?

 

[JohnW]

Is it a coating or is it just a 'soft touch' injection mould pattern?

IIRC, I believe its a spray on "silicon" coating.

 

[JohnW]

Hey John, when MDAC2 is finally ready for us all to set things in stone, etc., how are you going to announce it? Do we need to keep checking out this thread, or will you send out an email? Asking as I'm scaling back my PFM time these days... might miss something important though...

John,

Renata will PM you once we are ready

 

[JohnW]

Sorry for being absent for a few days while I've been worked on the Lab, wirings now in place, heating, Air-con, Airlines, network, security systems etc.... Now the decorator will be performing his magic and I can get back to work.

While I can ill afford the time, its important to have the lab completed for the MDAC2 / VFET Amp production before the bad weather sets, after installing the bundles of wiring I'm dreading having to install all the wall sockets etc. once the decorator has finished... Still I'm so looking forward to having the full lab back online - and having the space to employ someone to help out with production and PCB testing etc.

 

[misterdog]

Sorry for being absent for a few days while I've been worked on the Lab, wirings now in place, heating, Air-con, Airlines, network, security systems etc.... Now the decorator will be performing his magic and I can get back to work.

While I can ill afford the time, its important to have the lab completed for the MDAC2 / VFET Amp production before the bad weather sets, after installing the bundles of wiring I'm dreading having to install all the wall sockets etc. once the decorator has finished... Still I'm so looking forward to having the full lab back online - and having the space to employ someone to help out with production and PCB testing etc.

Are you introducing any acoustic treatments ?

 

[JohnW]

Are you introducing any acoustic treatments ?

Well not really, the wooden floor is mounted on rubber "mats" to dampen it & uneven bare brick work to defuse wall reflections - but there is a dedicated mains supply to the "listening" area...

I'll add rugs on the floor and a large soft sofa + curtains on the balcony window once the lab is completed.

I'd like to have a "representative" listening room, rather then a "fully treated" sonically "Dead" room.

 

[Steven Toy]

Well not really, the wooden floor is mounted on rubber "mats" to dampen it & uneven bare brick work to defuse wall reflections - but there is a dedicated mains supply to the "listening" area...

I'll add rugs on the floor and a large soft sofa + curtains on the balcony window once the lab is completed.

I'd like to have a "representative" listening room, rather then a "fully treated" sonically "Dead" room.

I like the 'sound' of that and hope to experience it for myself in the near future.

I am concerned though that rubber + wood is going to play havoc with speakers. Laminated floors are really not nice acoustically and this seems like laminate on steroids.

I would also anticipate 'smearing' effects on equipment placed on this type of flooring resulting in loss of dynamics, texture, imaging, separation and focus, bass overhang and 'bloom'. That rubber is going to 'sink' /store energy rather than 'ground' it.

I could be wrong of course.

I would prefer a solid floor plus underlay and carpet. Spikes can penetrate through that to the solid floor beneath.

 

[ChrisPa]

Ian

The initial software versions will output the digital data "unmodified" so no level control - however on later software builds once we start to perform the Level control with the FPGA we can also offer the option to adjust the SPDIF output level.

Excellent. Just what I was hoping for

 

[JohnW]

I like the 'sound' of that and hope to experience it for myself in the near future.

I am concerned though that rubber + wood is going to play havoc with speakers. Laminated floors are really not nice acoustically and this seems like laminate on steroids.

I would also anticipate 'smearing' effects on equipment placed on this type of flooring resulting in loss of dynamics, texture, imaging, separation and focus, bass overhang and 'bloom'. That rubber is going to 'sink' /store energy rather than 'ground' it.

The upper floor of the lab (the listening area) is supported by massive oak beams - with 25mm "partial board" I'm not sure of the English term, its not chipboard but larger chunks compressed into flat Tongue and grooved boards, then a thin layer of damping rubber, and then 22mm Tongue and grooved Oak floor boards.

The floor under the speakers is not supported by Oak beams, but 50cm wide thermal Breeze blocks, so a very sold mounting - more of a problem will be the Balcony triple glazed windows about 1.5m behind the speakers - I'm putting my faith into thick curtains.

We will see how it goes, I'm aiming for a typical domestic environment rather then an optimal room.

 

[fusion5]

Sounds good to me

 

[Steven Toy]

The upper floor of the lab (the listening area) is supported by massive oak beams - with 25mm "partial board" I'm not sure of the English term, its not chipboard but larger chunks compressed into flat Tongue and grooved boards, then a thin layer of damping rubber, and then 22mm Tongue and grooved Oak floor boards.

The floor under the speakers is not supported by Oak beams, but 50cm wide thermal Breeze blocks, so a very sold mounting - more of a problem will be the Balcony triple glazed windows about 1.5m behind the speakers - I'm putting my faith into thick curtains.

We will see how it goes, I'm aiming for a typical domestic environment rather then an optimal room.

I think I would still do away with the rubber - it is a nasty energy store. It is irrelevant to being a domestic environment or any other.

My own room is domestic; there are no room treatments as such. We also have lined curtains, carpet plus underlay which is soft and allows my kit to bed into it and 'ground' with the floor beneath. Additional stuff like another rug and two sofas serve to deaden the room and picture frames break up some reflections.

Lamp shades are fabric so they don't add ringing noise. They also match the décor.

 

[jirij]

I think I would still do away with the rubber - it is a nasty energy store. It is irrelevant to being a domestic environment or any other.

I guess that depends on one's belief and what the overall goal is. Coupling the speakers to the room (and the building) isn't always an obvious solution - the vibrations don't always go "to the ground". I guess we'll see how it works out for John.

 

[JohnW]

I think I would still do away with the rubber

No can do, the Rubber is there to prevent resonant vibration between the mating surfaces (Beams / Partial board / Oak Floor boards).

Tapping the structure without the rubber and it rings / buzzes, the rubber damps it dead.

Energy is not stored in Rubber, its converted to heat as the rubber molecules vibrate against each other.

Structure resonant "Buzzes" are very annoying - speaking from our current situation where the suspended ceiling resonates at certain Bass notes...