The original A16

[Conqueror's Reign]

How good is the original A16 compared to the current competition like the alesis AI-3 and the behringer ada 8000 and others? Would it still today be a good buy?

[hubird]

yes, at least that's said to be true (soundwise) in threads with this question that comes up so often these days, even speaking of the non ultra model

[astroman]

well, it's a bit like a 2-sided sword:
I like the audio quality a lot, but those units with 'regular' use are suspect to significant aging, emphasized by the supply power regulation (which could get quite hot) located below(!) the main circuit board.

my own A16 has developed occasional noise on some channels, and the noisefloor is not identical throughout the channels - symptoms have slightly increased since I bought it (2nd hand) a couple of years ago.
it's not exactly dramatic (and the box is still usable), but it's not perfect - ok, but then it's at least 7 years old and I almost never switch it off....

if you can get one for a reasonable price which you can tryout (connect each channel to a mixer and check the noisefloor), it's still a great buy today.
Its 18 bit converters will deliver 16 rock-solid most significant bits
The documentation mentions that the BNC outs are capable to supply a high quality studio clock signal.
Unfortunately there are no precision specs available, but the circuit itself does look impressive (it is a dedicated sub-section, not just a crystal), so imho that's a reliable statement. The unit was pretty expensive when new.

check the audio tracks forum for recordings by Wayne - all his analog stuff comes in via the old A16.
there are people who swear by this thing (occasionally reflected in eBay prices), and I will replace all electrolytic capacitors (parts with a limited life span) in mine - imo it's worth the effort.
more than 100 parts, tho... (if memory serves)

btw I know someone who had a Scope system some years ago, but he eventually sold it - except the A16, which he wanted to keep under all circumstances.

cheers, Tom

[Conqueror's Reign]

Thanks Astroman and Hubrid , yea i have seen posts where its said to be a great box but i also have read about this heat issue that makes the unit only good for so many years. I dont know if this a truth but i have read it in posts.

Astroman is it really that extensive a job to get rid of the heat issue? Is there a way to keep or make this unit run cooler?

[astroman]

no, I wouldn't consider this a 'rule of thumb' - you don't need it if an A16 performs well with a noise floor below 80 db, and all channels are more or less equal.
my box has some irregularities on 5 or 6 channels and it's usually faster to replace all parts than to search for the bad ones - it was also to meant to emphasize how much the unit is 'worth' to me

I assume that the internal operation level is 15V (and not 18V, which is also a common value with opamps) , but no diagrams are available.
My guess is from the fact that I run it from a fat 150W light transformer with rectifier diode network and capacitors that output exactly 16.3 V DC into the A16's power connector.
The unit gets only handswarm, as there's obviously 'less regulation' taking place than with the original PSU. The latter also had the typical 'voltage drop' by load (measured 'empty' it showed over 20V), which is pretty unlikely with the 150W transformer.
Of course this was no option on delivery - that transformer is a sell-out item from a supermarket, as noone buys halogene lights anymore since there are white LEDs...

And I'm not entirely sure about the dynamic range as I didn't measure values with the original PSU, at least it shows no obvious misbehaving...
NEVER run an old A16 from a notebook (or TFT monitor) switching powersupply, even if those have exactly the 18V spec printed on the backside of the A16. It will get hot as a boilerplate - and it won't sync anymore.
The 2 regulations work against each other, so to say

cheers, Tom

[hubird]

Is there a way to keep or make this unit run cooler?

you could use it upside down, to have the heat going up from above the board

[Shayne White]

Does the A16 Ultra have these heat issues??

Shayne

[ali]

Does the A16 Ultra have these heat issues??

Shayne

the original A16 used to have a fan on the left side to keep it cool

the new A16 Ultra does not have a fan and use better technology then the old one

however both sound good.

[hifiboom]

are the d/a converters on the new ultra version better concerning soundquality.?
I mean not only the technical details like bit depth.... where it is obviously better.

Sometimes old technology has the better sound....

[ali]

Quote: Sometimes old technology has the better sound....

true but not in the case of the A16 U.

converters are the same used for Scope cards.

[Shayne White]

true but not in the case of the A16 U.

converters are the same used for Scope cards.

...But without the added computer noise.

[katano]

no noise here

[Fede]

strange: my Scope Plus analog inputs have -85dB noise floor with nothing connected while my a16 ultra ins have -80dB (worse), is that normal?
I would have expected a16u to be less noisy being it an external unit...

Fede

[Conqueror's Reign]

Is the fan noise really an issue with the A16? I have read in posts where some have decided to turn it off.

[astroman]

1st it's annoying as it's one of those high speed 40mm things and 2nd it's rather uneffective as it blows over the top of the parts while the heat still 'burns' their bottom. It does prevent heat stuck, though if the A16 has a middle position in the rack.
As already mentioned it helps to mount the A16 upside down in the top position (or leave some space), or to put it on a solid metal plate to take some heat from it's bottom. Those 'tips' were of course marked as 'do at your own risk'

cheers, Tom

[Immanuel]

It depends. How noisy is the rest of your gear. My gear is not noisy, so I took out the fan. Tom did the same thing to his.

[Conqueror's Reign]

I guess it makes sense to off the fan if it is ineffective and just making noise seems there is not much lost doing that.

[astroman]

it may not be very efficient, but it is definetely required if the unit is mounted in a location with few airflow around it.
Btw memory betrayed myself, as there is indeed at least some airflow between the main circuit board and the regulation, sorry for the inconvenience...

Only if there's lot of free space around and/or the A16 is positioned downside up, the fan may be avoided (at own risk) - if a capacitor blows up inside (due to heat) there may be a short circuit as a follow up damage (in the worst case setting the unit on fire).
When I decided to turn the fan off I had the A16 on a table with a stone plate and I frequently checked how warm the case became - as it didn't exceed (imho) reasonable values, I kept it off.

cheers, Tom

[Conqueror's Reign]

Can the case be loosened just a tad bit to get a little more air thru it and is the fan loud enough to annoy a vocalist if the unit is in the same room?

[astroman]

well, it's not that dramatic - considering someone singing under headphones anyway.
Opening the case would have just the opposite effect, as the air comes in on the left side through a 40x40mm entry and is blown out on the right side through an equally sized outlet (rectangular) - that way an airflow is generated that would breakdown at any extra openings.
Acoustically shieding the outlet with some foam is probably most effective.
Btw that box is a hell to open - 32 nuts from the connectors, a tight supply cable and the BNC connectors have to be de-soldered to even get the cover off...
according to my memory
I am oversensitive to fan noise anyway and I live in a location that is extremely quiet at night - in fact it's so quiet that if the cover isn't on the PC I could hear the operation of my flash drive... don't laugh, it's not a joke... just to put this into some realworld context

cheers, Tom