How about this http://www.altavistaaudio.com/dact.html using Bent Audio's remote control system.
Byron
Byron
Why no remote controlled discrete resistor volume?
Shadorne, my experience is that I like the discrete resistor controls better than pots, because I sense greater clarity, definition and coherence. I only have one experience with a chip control (which I think sounds ok) but received some feedback on another forum; http://db.audioasylum.com/mhtml/m.html?forum=amp&n=159528&highlight=help+understanding+mitch2&r=&search_url=%2Fcgi%2Fsearch.mpl%3Fsearchtext%3D%26b%3DAND%26topic%3D%26topics_only%3DN%26author%3Djnr%26date1%3D%26date2%3D%26slowmessage%3D%26sort%3Dscore%26sortOrder%3DDESC%26forum%3DALL I found it interesting that while they thought the PGA2310 was an upgrade of the CS3310 from Cirrus Logic, they still found the chip controls as a group to be crappy, including the PGA2320 in the $10K Esoteric C03. |
Byron - that's great! I was not aware anyone had accomplished that. I still find it amazing that something so simple and relatively inexpensive (compared to the $5K+ preamps we purchase) has not been implemented by more companies compared to using a basic volume pot. Thanks also Ngjockey, although the Altavista solution is more what I was looking for. |
John Chapman does a number of resistive based remote units using logic and high quality relays to do the switching. http://www.bentaudio.com/remotes/oem.html dave |
Motorizing a switched control can be a bit of a trick. You can have some torque to overcome, if the switch is worth a hoot. No way are you going to see this for $35.00! I've been watching the chip technology for 17 years now. The new ones are a lot better, but to this day if you have a state of the art preamp, those chips will shoot the preamp down before it can even get off the runway.... You did not mention relay operated controls but they are the next best thing to a motor turning a switch. So that makes the chip controls 4th on the list. Bent Audio is one of the better places to look if you want to do a remote properly. |
Blue Circle makes one as well. http://www.flickr.com/photos/17843311@N00/3768616815/in/set-72157619245521825/ |
I had a DACT in the TEAD Vibe I used to own. I liked the sound of that preamp for solid state. Resolution was quite good, but I have heard better dynamics and better high frequencies. Nikki, I am sure Gilbert's Blue Circle attenuator sounds outstanding, although installation could be a challange in most normal sized preamps. Thanks for the picture. |
Ralph, I was not clear. I was pointing out how manufacturers of very expensive preamps use a low cost $35 part for one of the most critical aspects of a preamp - the volume control. My experience indicates the volume control is important to the sonics, and that spending $300-$500 or so for a quality volume control is totally reasonable for a preamp costing $5K and up. Based on the posts above, it seems the options are available but the manufacturers using the less expensive pots either decide the benefit does not improve sonics, or that they can sell preamps without the more expensive (and better sounding) volume control and that the remote option is more important. Some like at Joule, indicate the volume control is "outside of the signal path" and that their use of a pot doesn't matter. I do not quite understand how that works. |
Mitch2, your experience is correct. There is no way around the fact that you have to control the volume; the more revealing your system is the more you have to make sure that the volume control is not messing things up. You can get the control outside of the signal path by having it control the gain of the circuit rather than the signal level getting to it, but by no means does this allow you to skimp on the control. Anyone who has heard the effects of good quality resistors will understand this. |
Mitch2, Gilbert's VC is big and barely fits in my pre which is over 14" deep. He had to install a little cap on the end so that the end of the motor could stick out a little past the chassis. He may be able to make it a little shorter, but you would need to ask him. It works really well and is a no compromise remote VC using Shallco attenuators. It requires quite a bit of torque and virtually impossible to turn by hand. |