Senior Member
Location: Surrey
Posts: 7,219
I'm Rob.
The guy who calls his version the Lampucera, says that the chip supports balanced operation. It seems that you can get a balanced out by connecting 4 wires plus grd to the vacant pads left by removing c27, c28, c30 and c31 ?
http://www.lampizator.eu/LAMPIZATOR/...ampizator.html
Trade: Longdog Audio
Location: Halifax, UK
Posts: 1,394
I'm Nick.
Ah, another who has tried the JVC, I built one up a month or so ago, and it was remarkably good, it was more of a shock when it went to its owner and I had to go back to my old tosh DVD as a transport. Mo on here was at mine at the time and he heard what a difference it made.Originally Posted by iihay
I have another still in its box to try when I find time, but I might see if I can connect it directly to my DAC I am working on, as the chip on the transport does have a digital (not the spdif one) output, its just not i2s, but I should be able to manipulate that into i2s in the cpld I am using.
Senior Member
Location: Cheltenham U.K
Posts: 412
I'm John.
That's right. If you remove the caps you will see the pads are marked R+ R- L+ and L-.
Senior Member
Location: Surrey
Posts: 7,219
I'm Rob.
Goody Goody, more time spent bodging !. I bought a kit from White Noise years ago to accept a balanced in and balanced out. I didn't then and haven't since had a pre with balanced inputs, but I found a significant improvement by using the balanced outs on a Dacmagic and into the module and out as single ended. Far superior to the single ended outs. So, will have to give it a go.
Member
Posts: 34
I'm planning on buying a couple more for tinkering. They are hard to find but ASDA near me has loads left
Iain
Circuit Junkie & DIY Room Forum Leader
Location: Notts UK
Posts: 1,804
Yes, the dac chip already has differential outputs so running balanced is easy enough
Senior Member
Location: Cheltenham U.K
Posts: 412
I'm John.
I have finally got my board working at 96kHz, thanks to some help from error401 over at diyAudio. In case anyone is interested, the mod. involves lifting pin 2 of the CS4397 (to remove its ground connection) and wiring it direct to pin 16 of the CS8416. The board will then process all sampling rates up to and including 96kHz (and maybe 192kHz, though I'm not able to test that).
Doing this involved micro-surgery more delicate than I generally care to undertakeso don't do this at home unless you have to, or you are comfortable with such things. It does sound really good at 96kHz, though!
Last edited by jonners; 17-06-2008 at 17:56. Reason: additional information
Senior Member
Location: Chester
Posts: 429
That's a useful discovery, nice one.
I've come to the end of my search for the ideal input capacitor. Vishay/ERO MKP1837 0.1uf does most things very well indeed, and as a bonus it actually fits on the board. Quite happy with it all now.
Senior Member
Location: Surrey
Posts: 7,219
I'm Rob.
I've now got mine working in balanced mode. IMHO much better than single ended.
jonners. Is that all there is to it (96khz) direct connection from pin to pin ?and you get 44.1 and 96khz ?
Senior Member
Location: Cheltenham U.K
Posts: 412
I'm John.
Yes it will then receive and convert a 96kHz signal but it won't upsample of course. You have to lift pin 2 of the CS4397 away from its ground connection on the board. Its no use trying to cut the trace leading from it - possibly the pad connects to the ground plane in some inaccesible place under the board. You then solder a thin wire from that pin to pin16 of CS8416 - no need to lift pin 16.
I'm using balanced out too - direct into a TVC. I found that with no filtering after the dac outputs the hiss level rises somewhat, so I'm experimenting with a bit of passive filtering. At present I've got the + and - outputs going through series resistors of 240 ohms followed by 2.2nF bridging between + and -. That cuts the noise out, but I might experiment with slightly smaller caps.
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