In short in many ways its as good or better than any commercial DAC. It has more output drive and lower distortion than all but a few of the latest premium DAC's. Here is a plot of an extremely challenging test signal- http://www.diyaudio.com/forums/equi...n-audio-range-oscillator-686.html#post5116959 If you look closely its really free of HD and IM products.
The short time I have had to listen to it (need to get the audio system back up) it sounds really good.
The short time I have had to listen to it (need to get the audio system back up) it sounds really good.
Hi Demian,
That's $1,000 well spent. Many audiophiles spend much more and get substantially less performance.
So, would you describe it as sounding "clinical" ?
Hi manpowre,
Personally, I think the project is fine for timeline considering it's a full-blown commercial product with a company behind it. I'm pretty pleased sitting here waiting for such a capable piece of test equipment that I couldn't afford to get any other way.
The only thing that would make me happier is a big honking box with flashing lights, displays and switches along with the front panel jacks. How about a large LCD (or whatever is the current darling of displays) to show the data. But that would mean using an internal computer and the price would skyrocket. I guess I'll take it as it comes. Can we at least have a big honking box? Actually, in my situation, a 19" rack case would have been perfect. I'll probably try and mount it in a panel somehow to keep it off the bench surface. Also the connections are easier to make if it isn't skidding all over the place.
-Chris
That's $1,000 well spent. Many audiophiles spend much more and get substantially less performance.
So, would you describe it as sounding "clinical" ?
Hi manpowre,
Personally, I think the project is fine for timeline considering it's a full-blown commercial product with a company behind it. I'm pretty pleased sitting here waiting for such a capable piece of test equipment that I couldn't afford to get any other way.
The only thing that would make me happier is a big honking box with flashing lights, displays and switches along with the front panel jacks. How about a large LCD (or whatever is the current darling of displays) to show the data. But that would mean using an internal computer and the price would skyrocket. I guess I'll take it as it comes. Can we at least have a big honking box? Actually, in my situation, a 19" rack case would have been perfect. I'll probably try and mount it in a panel somehow to keep it off the bench surface. Also the connections are easier to make if it isn't skidding all over the place.
-Chris
Hi Kevin,
I was thinking of this as a separate thing entirely. There is no way Jens would change so much as a screw position now I don't think.
I'd make room for the Amber (which is an excellent instrument) if I were you. I think it is more capable than anything I have right now in fact. Sad to hear you have one that is rarely used.
As for rack space, it is easy to create once you know the depth you need. I had to go back 24" or so, and 30" for the rack for the network analyser. Its all very heavy stuff. Anyway, having stuff in a rack is a wonderful way to keep stuff off the bench if planned properly. I did the gear-on-bench thing for years, had a semi-rack system, and finally a full rack system where it was easy to accommodate non-rack gear.
-Chris
Edit: I see the audio analyser as adding to the clutter since it also needs a power supply and wires between them. It certainly would be in my world.
I was thinking of this as a separate thing entirely. There is no way Jens would change so much as a screw position now I don't think.
I'd make room for the Amber (which is an excellent instrument) if I were you. I think it is more capable than anything I have right now in fact. Sad to hear you have one that is rarely used.
As for rack space, it is easy to create once you know the depth you need. I had to go back 24" or so, and 30" for the rack for the network analyser. Its all very heavy stuff. Anyway, having stuff in a rack is a wonderful way to keep stuff off the bench if planned properly. I did the gear-on-bench thing for years, had a semi-rack system, and finally a full rack system where it was easy to accommodate non-rack gear.
-Chris
Edit: I see the audio analyser as adding to the clutter since it also needs a power supply and wires between them. It certainly would be in my world.
It used to live on my bench, but I never, ever used it, defaulting to the FFT system when it worked, and the 3501A for source and basic thd+n or gain measurements. (It's actually better than a 5500 even with all of the high performance options.)
FFT is much more useful IMO in my design process. I can compare FFT generated in Spice with those measured on a piece of equipment I have designed - way more informative than the simple numbers the Amber gives me.
If you lived closer I'd loan it to you..
FFT is much more useful IMO in my design process. I can compare FFT generated in Spice with those measured on a piece of equipment I have designed - way more informative than the simple numbers the Amber gives me.
If you lived closer I'd loan it to you..
Hi Kevin,
The feeling is mutual, but that's okay. I would love to try one out some day if someone who has one lived closer to me. I have heard that the 3501 was a little better.
I generally use the THD meter (HP 339A) and use the FFT on the residual from the THD meter. That acts as a tuned filter for the fundamental and I can extend the range of the FFT instrument (HP 35665A), but the absolute levels are in question doing it that way. At least I can see into the noise. My problem is that a lot of my work is under the noise floor of the 339A these days.
-Chris
The feeling is mutual, but that's okay. I would love to try one out some day if someone who has one lived closer to me. I have heard that the 3501 was a little better.
I generally use the THD meter (HP 339A) and use the FFT on the residual from the THD meter. That acts as a tuned filter for the fundamental and I can extend the range of the FFT instrument (HP 35665A), but the absolute levels are in question doing it that way. At least I can see into the noise. My problem is that a lot of my work is under the noise floor of the 339A these days.
-Chris
This will give a better idea of the size and scale of the RTX vs. 19" rack devices. Its a little more than 1/2 rack. A little larger than my Keithley 2015. Rack mounting would be pretty simple but wasteful unless you can use the rest of the space for other useful things.
Attachments
Or additional a Notch (tun-able, fixed 1/10khz and post notch gain amp) after the attenuation...
and all remote switchable from a tablet sitting in a couch hp
Lots of great ideas for improvements
And who knows, some of them might find their way into a future model.
Along the way I have built some designs to test various ideas, like a 1 kHz bandpass filter, to reduce the distortion from the DAC, a passive 1 kHz notch filter, in order to verify the DAC performance and a low distortion 1 kHz oscillator, to verify the performance of the input amplifier and the ADC.
Some of these could be be included into an upgraded model. But if it will ever happen is an open question.
I did think of using a 19" box. Actually the first (partial) prototype was built into a 19" Schroff box. But I wanted to make a smaller unit and I don't like the sharp edges on the front plate of the 19" boxes I used. So it might have to go into a desktop enclosure, unless used in a rack system.
You can get brackets for the box I used. These will allow you to mount it on a 19" front plate with a suitable cut out.
I didn't really think of HpW's remote control idea, but i guess it shouldn't be too difficult these days
One of the things on my to-do list is a digital I/O. This might be included in a follow-up model. But it won't make it into the group buy version.
Jens
And who knows, some of them might find their way into a future model.
Along the way I have built some designs to test various ideas, like a 1 kHz bandpass filter, to reduce the distortion from the DAC, a passive 1 kHz notch filter, in order to verify the DAC performance and a low distortion 1 kHz oscillator, to verify the performance of the input amplifier and the ADC.
Some of these could be be included into an upgraded model. But if it will ever happen is an open question.
I did think of using a 19" box. Actually the first (partial) prototype was built into a 19" Schroff box. But I wanted to make a smaller unit and I don't like the sharp edges on the front plate of the 19" boxes I used. So it might have to go into a desktop enclosure, unless used in a rack system.
You can get brackets for the box I used. These will allow you to mount it on a 19" front plate with a suitable cut out.
I didn't really think of HpW's remote control idea, but i guess it shouldn't be too difficult these days
One of the things on my to-do list is a digital I/O. This might be included in a follow-up model. But it won't make it into the group buy version.
Jens
The PCB's could go into a similar 19" box if you really want it to. But that would involve a lot of drilling of holes. I don't have a 19" box prepared for it. The one I used for the early test circuit is too small and was reused from another project, so it didn't exactly look good either.
Hi Jens,
Is it possible to make the digital I/O user-upgradable for the GB version?
Thanks
Paul
Yes, I do remember the discussion of adding digital I/O to the GB version, which is too late to change the design because this product has passed all the necessary EMI/EMC tests. However, I am just hoping to have some pins or a socket inside the GB version for the future digital I/O daughter board, as long as the product does not have to be sent to do EMI/EMC certification again with this (minor ?) change.
Interesting protection circuitry.. news to me, maybe not to you guys.
Too late for this rev anyway, but figured I'd share.
Overvoltage Fault Protected Analog Switches | Analog Devices
Too late for this rev anyway, but figured I'd share.
Overvoltage Fault Protected Analog Switches | Analog Devices