|
|
Post by tonycamphd on Mar 29, 2015 19:39:59 GMT -6
It has a bit more setup than what has been eluded to. There are a bunch of dip switches that need setting. There is also 2vdc coming out of the inputs that you need to watch out for, you can't use it with transformer outputs without some kind of dc blocking. You also need to put it in a box and the connections are not all on one side of the board, so you'll need to do that wiring along with building a quiet power supply. One last thing, the board has no screw holes so no good way to affix it in the box, and also suffers a bit from ground noise because of this. I did read the PDF of the board and it seems no to hard. But on the other hand it will need time. And if there is even a tiny problem there is lack of experience. I will rethink it start. Maybe if a few of us go for it at the same time? reading that makes me feel like i can build it as well, weird, only a couple of years ago i'd have looked at that and been like "what are ya kiddin me?" 8) |
|
|
|
Post by gouge on Mar 29, 2015 21:14:16 GMT -6
you can pick up a Tascam da3000 for under 1k or a second hand korg unit for less.
either way. dsd
|
|
|
|
Post by jimwilliams on Mar 30, 2015 9:57:24 GMT -6
The dip switches are set for 48k out of the box, switch those if you need a different rate. The data sheets have all the switch combos spelled out. Add 4 wires and go, +15, -15, +5 and ground. There is no ground noise on this Burrbrown designed EVM (evaluation module). It was layed out to show the capabilities of the chipset and was done well. Just use a quality low noise power supply. I built mine with Linear Tech LT1085 and LT1033 adjustable regulators, those give me a very clean rail with far less noise than common regulators like 317/337's.
Yes, it's a bit of a DIY thing, but most with patience and thoughful care will make it work as many have over the years. It was quite the rage in Nashville when these became popularized. It's easier than building a mic for example.
|
|
|
|
Post by svart on Mar 30, 2015 10:30:21 GMT -6
So what about the opa1632 diff amp? You've mentioned more than a few times how much you dislike it.. however it is in a tiny msop package and has no direct substitutions..
|
|
|
|
Post by mrholmes on Mar 30, 2015 11:02:19 GMT -6
you can pick up a Tascam da3000 for under 1k or a second hand korg unit for less. either way. dsd Yupp have seen the DA 3000 yesterday at my retailer. www.tascam.eu/de/da-3000.htmlWhich one is the Korg Unit? |
|
|
|
Post by gouge on Mar 30, 2015 16:42:06 GMT -6
I use the old korg mr-1000 and there is also the mr-2000
|
|
|
|
Post by Johnkenn on Mar 30, 2015 21:34:46 GMT -6
Er...That's more than a little complicated...especially when an already built one can be had for around $450. (We are just talking AD here, right?
|
|
|
|
Post by jimwilliams on Mar 31, 2015 9:44:54 GMT -6
So what about the opa1632 diff amp? You've mentioned more than a few times how much you dislike it.. however it is in a tiny msop package and has no direct substitutions.. I ran that for a couple of years and decided to try an opamp based replacement. When the ADA4898-1 was released, I built up some perfboards with the circuit shown on the PCM4222 data sheet, Figure 51 on page 32. I replaced the 560 ohm input resistors with 1k ohms to achieve digital zero at +20 dbu. Now you know where my recommendation for the ADA4898 opamp as an input buffer came from. Give credit where credit is due, so said me mum. |
|
|
|
Post by bradd on Apr 11, 2015 20:24:15 GMT -6
Thanks, Jim,
|
|
