Hi!
What will you suggest?
I use it as a active crossover before the amps
I want to control the volume from a distance, ~ 5m.
Is there a good easy cheet out there for a good active 6ch controler?
Passive will be to destructive on the signal? Or maybe a digital volume pot?
Thanks for any tips!
you get the idea with this:
What will you suggest?
I use it as a active crossover before the amps
I want to control the volume from a distance, ~ 5m.
Is there a good easy cheet out there for a good active 6ch controler?
Passive will be to destructive on the signal? Or maybe a digital volume pot?
Thanks for any tips!
you get the idea with this:
a volume controller has to adjust all 6channels by the same attenuation to get effective channel matching of the levels arriving at the power amps.
You can do this passively if you get the source impedances low enough to become effective drivers of the long cables. This is the easy bit if you use Buffers.
You also need a good balance of attenuation between the channels. This is the difficult bit.
Jan Didden designed a kit to do this inside the DCX. It may be possible with a few mods to make this into a remote adjuster.
You can do this passively if you get the source impedances low enough to become effective drivers of the long cables. This is the easy bit if you use Buffers.
You also need a good balance of attenuation between the channels. This is the difficult bit.
Jan Didden designed a kit to do this inside the DCX. It may be possible with a few mods to make this into a remote adjuster.
A volume control is an oddly challenging problem with numerous issues starting with deciding the location along the chain. I've concluded that ganged pots just ahead of the amps is the place to control volume so that all the devices upstream and right through the 2496 will not lose any digits. How to do that at 15 feet away is another question. Unless you love ping-pong over ambience or beautiful dipole sound, exact channel balance is a non-issue.
It may be appropriate to (again) mention what I think is the best configuration with a 2496: put all your music on a little chip-card plugged into your computer (and I have my music all databased in FileMaker that also plays the files) and drive the 2496 with a USB-to-AES converter. That makes the most of the system digital. BTW, with that kind of line-up, you can use your smartphone to control your computer (including volume, if you want to control it that far upstream). Good way is iPhone and iTunes.
Not everybody knows that ripping your CDs to a lossless (but compressed) computer file (such as Apple Lossless) results in a cleaner data stream than playing that CD in real time.
I've also wired-up another wireless link for some rooms: after your computer-source. Pretty credible fidelity using WiFi (not BlueTooth) to a Sonos or Apple Airport Express (not AP Extreme!!!!). So, so fidelity using BlueTooth to any number of self-powered speakers available.
Many options, eh.
Ben
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Viper,
You might start here, DCX2496 active output mod & 6-channel vol control | Linear Audio NL,
Have Fun!
NS
You might start here, DCX2496 active output mod & 6-channel vol control | Linear Audio NL,
Have Fun!
NS
Thank's Jan! will check that out.
Personaly i think this will be more pleasant sounding than a digital bit loss volume from the windows program(dcx rem) that i have now. But you have to place it next to the unit: Big Blue - Page 3
Personaly i think this will be more pleasant sounding than a digital bit loss volume from the windows program(dcx rem) that i have now. But you have to place it next to the unit: Big Blue - Page 3
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I guess it depends on what you consider worse - the quantization noise from losing some low bits vs. the noise level of the analog inputs of the DCX2496. The analog input dynamic range is specified as 109 dB (equivalent to 18 bits), so for the first 36 dB of attenuation, the digital attenuation is superior.
The audibility of "bit loss" at such low levels is another discussion...
You seem knowledgable about these matters, so how about explaining it further.
For example in the system I'm finishing, I remain digital from the USB port, into AES, into Input A. Then my plan is a 4-gang voiume control into three or four power amps (and with other VCs on downstream amps).
On the basis of standard level digital signals going into the DCX, what analog voltage comes out the far end?
If I need to cut the DCX output by more than 36 dB (95%) downstream for ordinary/critical listening levels, you say I'm better off trimming loudness with an analog VC after the DCX and leaving everything upstream full bits?
Ben
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4-gang volume control directly on the DCX outputs, without buffering? What input impedance do your amps have, and what value pots are you planning to use?
Depends on your filter settings, of course, but you are basically still limited by the +22dBu (approx. 10 V rms) maximum output level of the DCX.
I would say that if you need to cut the DCX output by that much, you should look at the gain structure of your amps. I would adjust the gain of the amps so that close to maximum level output from the DCX gives you the maximum volume you ever need, and then use digital volume control to reduce it to "normal" levels.
my dcx2496 with 2 v200 digital amplifier in i2s.
One remote , no dac, less cable. the best sound with my dcx (battery 7.4v 65ah, regulator lt1963 etc).
Cool!
Can you please describe how you wired your setup?
--source--> dcx --> and so on.
Julf - many thanks for your in-depth reply.
From memory since I am on vacation now, i have ganged four nice small Bourns audio pots, about 20kOhm, going into amps with about 80kOhm input rating (starting with 100kOhm VCs). Should be OK passively (esp at middle rotations), but I can buffer with an op-amp if not.
I gather from what you say that going full digital results in clean, low noise DCX output of about 10v. From there downstream, my only volume controls are the ganged Bourns and the input VC on the amps. In other words, "adjusting the gain structure of my amps" is all in the those VCs, since I hesitate to touch the feedback loops inside my amps.
So by measurement or by ear, I gather you recommend using the analog VCs to set the amp inputs at max listening level (say, about 1 volt, representing a loss of 20dB in the Bourns VC) when all the digits are playing and to use my music player's digital control (iTunes or QuickTime player) for quotidian adjustments?
Ben
Footnote: having said all that, I am very happy with the low noise and good sound from my stock DCX which has been running for two years very rarely peaking as high as 3 LEDs (which is pretty low, with analog inputs. But running full LED scale, with most of the digits inputted as described above, sounds appealing.
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Those values should be more than large enough not to cause any issues with the output impedance of the DCX.
Yes, but as the analog volume/gain adjustment is pretty much a one-time thing, you might look into a fixed attenuator (basically 2 resistors per channel), as an attenuator is smaller, cheaper, less noise-prone and probably more linear than a potentiometer.
Again, I appreciate your sound advice. Inexpensive ganged pots as VCs can lose synch and be noisier.
In practice, depending on how good I can see my laptop screen and how long my arms are, the Bourns VCs may be the quotidian adjustment next to my listening chair. Hard to say yet. Also, I haven't finished exploring the wonderful world of smartphone laptop remote controls apps.
Ben
Fair enough - and I doubt there is an audible difference either way.
Let us know what you end up using!
older Yamaha recievers like rx-v657 have a digitally controlled analog multipot.Hi!
What will you suggest?
I use it as a active crossover before the amps
I want to control the volume from a distance, ~ 5m.
Is there a good easy cheet out there for a good active 6ch controler?
Passive will be to destructive on the signal? Or maybe a digital volume pot?
Thanks for any tips!
you get the idea with this:
and actually pretty nice amps to, but these have multi pre outs untainted by adda uglieness. Its the best way to go. I run my stuff through jriver and back out this way.
So called Bit Loss is overrated. The DCX has 24 in its name because it works in 24 bit. That means in the DSP you have 144dB of range. That's enormous. The AKM chips aren't that good, and the stock analog section certainly is not. But if you use a decent output stage, I used transformers, then no worries with 10-12 dB of attenuation. You're still better than 16 bit.
I set my power amp gains to use the full range of he DCX outputs, as far as possible. I use digital volume control going in. No worries. I measured, I listened, I tested. It's probably better than analog volume control. If you need to use the analog inputs of the DCX, build a better input stage (it's easy) and use a volume control in front of that.
Some goofball wrote an article about all this; it's over in the articles section of the site.
I set my power amp gains to use the full range of he DCX outputs, as far as possible. I use digital volume control going in. No worries. I measured, I listened, I tested. It's probably better than analog volume control. If you need to use the analog inputs of the DCX, build a better input stage (it's easy) and use a volume control in front of that.
Some goofball wrote an article about all this; it's over in the articles section of the site.