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Analogue RCA input expander recommendation ?

tw99

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I use a Dspeaker Antimode 2.0 as the DAC and room correction device in my system. While I've seen at least one technical review that suggests this device doesn't measure brilliantly well, subjectively I don't have any problems with it, and I really like the features and flexibility it offers, so I'm not intending to change it.

I'm currently using an ATC integrated amp to drive ATC speakers, so I effectively have two pre-amps in the system.

I could potentially replace the ATC amp with a power amp (maybe an Ncore-based unit), and just use the Dspeaker as the pre-amp. The main issue with this is losing analogue inputs as the Dspeaker only has one, so I'd need an input expansion device to cover 3 analogue inputs.

Are there any recommendations for an affordable and technically competent analogue input switcher for unbalanced RCA connections ? I see that Amir reviewed a couple of similar devices recently, but both of those had volume controls which I don't need. It'd be nice to have a device with remote control, but a manual one could be OK as I mainly use one analogue source.
 

sergeauckland

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gene_stl

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I am interested in a similar but not quite identical problem. I am planning expansion from 2 Ch to five or seven dot one or two.

I have an Oppo 205 which is quite talented and has a dedicated "audiophile stereo out" as well as 7.1 outs both balanced and unbalanced.

I also have a Marantz AV preamp processor (AV7005) which came to me. This also has both balanced and unbalanced out.

The big speakers at the moment are driven by a Pioneer D-23 crossover which is UNbalanced only inputs and outputs. I also have some newer pro crossovers which I haven't tried yet, as well as being interested in some multichannel DACs. Also I have had some pro balanced input amps fall into my lap too.

Consequently it would be nice to , for example be able to switch the crossovers between the SchMarantz and the Oppo, not to mention future Okto or whatevers. Because of how well the Oppo has measured here I would like to use it directly to drive the crossovers and sub amps.

China Incorporated has an interesting variety of switch boxes , mostly aimed at the do it yourself, put it in your own box market. These look good to me. Has anyone used such things.

I have considered just getting a set of three or four passive switch based devices or building something similar. You couldn't get into too much trouble with switches only. Much to my surprise I just saw a character assassination piece on mercury reed relays. Check Linear Audio volume #14 and one of the author's no less an authority than Bruno Putzeys. Perhaps Amir would like to see whether he can replicate their findings.

Reed Relay Distortionpreview
Reed Relay Distortion
v13%20sg%26bp%20abstract.PNG

In this brief article authors Groner and Putzeys discuss nonlinear distortion in reed relays. Measurement data is presented as well as simple model to estimate the 3rd harmonic distortion contribution in a circuit. The authors have tested several types and found no substantial difference regarding their distortion behavior.






Alie Express Page

A suspect

diy kit from hackaday Tindi kit of same for $69
 
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tw99

tw99

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sergeauckland

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Thanks for the reply @sergeauckland . That link gives me a list of 225 products, do you have an exact link or the name of the one you use ?

The first one on that link is like the one I use, but I now can't find any that don't also have composite video switching as well as L&R audio. As these boxes are entirely passive, there's no harm in buying one with the extra video path and just ignoring the extra sockets.

You can always use the video channel to switch S-PDIF, as composite video and S-PDIF are both nominally 75 ohms, although for short cable distances, digital audio is very uncritical.

They can also be used in reverse, for switching one input to four destinations. Very simple and inexpensive.

S.
 
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