Topic: Anyone running a mic2496 in front of a JB3?

[pfife]

Soliciting opinions/experiences/disadvantages of this pre/AD in use with an NJB3.

Thanks in advance.

[setboy]

i think some one with the name MATTZS or MATTSZ runs one


Raphael

[Brian Skalinder]

Disadvantage:  The Mic2496 only outputs 24-bit word length, so the JB3 will truncate it down to 16.

And, it's a Core-Sound product.  I'll let you decide whether that's an advantage or disadvantage. 

[sml42]

Originally posted to the recent "critique your rig" thread by me:

Mic2496. Basically, don't bother. I've had a switch break off... it
drain a battery in a blink... it is totally unsuited to the dpa4060 I
bought with it (the mic2496 gain is too high... even on the low
setting it brickwalls pretty much anywhere) although I concede a
dpa4061 may be a better match... and the battery life (when working
well) sucks (at the exact point where the battery low indicator comes
on... the output from the ADC mutes! Absolutely zero chance to change
batteries at a convenient point... grrr).  Oh yes, and it's sold by
core-sound.  Now I concede that other people may or may not have had
better experiences than me, but.. well.. coresound basically jerked me
around, so I shan't be deaing with them again ever (my order was
originally "lost", they didn't respond to emails... needed constant
badgering on the phone... took 7 weeks for me to actually receive what
I'd ordered.... no thank you).

I think I ought to add a little more to my original comment... I was not in a great frame of mind when I wrote that, so I do want to say this of the mic2496: when it works, it sounds very good.  Here is a sample: http://www.landamore.com/bw2004-07-17t02.flac (Brian Wilson, New Theatre, Oxford UK... DPA4060 ("high boost grid" fitted) > mic2496 > jb3.  My location... the audience... the sound... brian fucking WILSON, dammit!... this was going to be an absolutely KILLER tape... but oh no, the mic2496 decided it was going to eat the battery... drained flat in 4 songs time. Was I ever angry. I've not used the mic2496 since, and I'm not sure I will again.

The switches. Two switches to select 44.1/48/88.2/96, but the switches are not clearly labelled! No documentation came with the mic2496... I had to record a test tone at each of the 4 positions, to work out where to set my switches... which is simply needlessly annoying.

As I wrote previously, one switch broke off. This was the P48V switch... fortunately this switch is redundant, since my mic2496 was configured to provide the correct voltage to power my dpa4060 mics... but even so it doesn't inspire confidence in the build quality. Just taking the lid off... looking inside... yeah it has great specs (on paper) but it doesn't strike me as being terribly well put together... a nice 4 layer PCB, well laid-out if a little cluttered... and mounting holes that don't line up properly... it has been well engineered, but not put together well, if you get my drift... like it was 90% designed meticulously, then the last 10% was thrown together... it is confusing to me, why someone who so obviously set out to design a real high-end part... why is it in a shoddy bent aluminum case? it just doesn't make sense (and I speak as an electronics engineer, so hopefully with some authority).

One thing I would have liked... the mic2496 doesn't have a belt clip.

And my experiences dealing with core sound were very negative.  Never again.

But.  When it worked, it worked well. Listen to my Brian Wilson clip above for proof. Of course as Brian wrote, feeding mic2496 > jb3 will truncate from 24- to 16-bit...

There. I've vented. I feel better now... I'll shut up :-)

best regards,
stephen

[lds490]

My Mic2496 outputs 16 and 24 bit.  I've never used anything else so I can't compare, but I think it works fine.  The switches to change sample rate are a little confusing.  It outputs both coax and optical.  Core sounds is a pain in the ass to deal with.  I've never used it with a JB3, but I don't see any reason why it would not work just fine.

[BC]

My Mic2496 outputs 16 and 24 bit. 

Do you know if it dithers or just truncates to get the 16 bit output?

Just curious.

[sml42]

My Mic2496 outputs 16 and 24 bit. 

Do you know if it dithers or just truncates to get the 16 bit output?

Just curious.

Actually the mic2496 outputs 24 bit always. I looked into this some time ago, it is basically outputting a standard S/PDIF signal. A S/PDIF frame is basically 32 bits: 24 bits of data and 8 bits of control. One of the control bits indicated whether this was a left/right sample, and I forget the rest of the control bits. Probably framing and copy protect (SCMS) I would imagine. If you look on the wire, it is a continuous stream of 1s and 0s, clocked at a different speed depending only on the sample rate.

Likewise the JB3 accepts a standard S/PDIF signal input. Which means it will ALWAYS receive 24 bits... except the JB3 will truncate, and only save the 16 most significant bits.

Similar story with the AD-20, except that only uses a 20-bit ADC.  How does that work? Well, it also outputs a standard S/PDIF signal... 24 bits of data, plus 8 bits of control (= 32 bit frame). Obviously the ADC fills in the first 20 data bits... but what about the other 4 data bits? Simple: they are 0. It's like the difference between writing 0.123 and 0.123000 (i.e. no different). And if you feed the ad-20 into a jb3, it still truncates at the same place (this time throwing away the four 0's along with the four least significant bits of real data).

best regards,
stephen

[lds490]

My Mic2496 outputs 16 and 24 bit. 

Do you know if it dithers or just truncates to get the 16 bit output?

Just curious.

Actually the mic2496 outputs 24 bit always. I looked into this some time ago, it is basically outputting a standard S/PDIF signal. A S/PDIF frame is basically 32 bits: 24 bits of data and 8 bits of control. One of the control bits indicated whether this was a left/right sample, and I forget the rest of the control bits. Probably framing and copy protect (SCMS) I would imagine. If you look on the wire, it is a continuous stream of 1s and 0s, clocked at a different speed depending only on the sample rate.

Ok, so what is happening when I switch my Mic2496 to 16 bit output?  Is this different from any other ADC?

[sml42]

Ok, so what is happening when I switch my Mic2496 to 16 bit output?  Is this different from any other ADC?

You've got me confused there. How are you selecting 16-bit output? The two switches (X1, X2) only select the sample rate, not the bit depth. You should still be getting a full 24 bits, even at 44.1kHz. Unless there is some internal jumper you've been changing?

best regards,
stephen

[lds490]

Ok, so what is happening when I switch my Mic2496 to 16 bit output?  Is this different from any other ADC?

You've got me confused there. How are you selecting 16-bit output? The two switches (X1, X2) only select the sample rate, not the bit depth. You should still be getting a full 24 bits, even at 44.1kHz. Unless there is some internal jumper you've been changing?

Sorry, my mistake.  I wrote before I thought.  The mic2496 outputs 24 bit and I control bit depth with the recording software.  Now I'm wondering if the software dithers or truncates.  It does not make a big difference to me because I record mostly in 24 bit anyway.