# Preamp: Digital in + digital out "tape loop?"



## spreston (May 21, 2008)

Hi Guys:

I am upgrading my pre/power amps and hope to smoothly integrate the DEQ2496 for 2.1 channel use. 

I am looking to utilize the DA processor of the preamp for all sources and bypass the DEQ's DA processor by
* using the DEQ's digital in/digital out connections (and corresponding digital in/digital out connections from preamp, acting like a digital "tape loop")
* not using the analog tape in/tape out to connect the DEQ (my current method)

I just looked at a Sunfire TG2 which has a well rated DA processor. But Sunfire customer support confirmed that despite having digital in and digital out connections, I could not set up a digital in/digital out "tape loop." 

Are there any preamps that will allow me to set up a digital "tape loop" and avoid purchasing yet another DA converter? How have others dealt with DA conversion on the Behringers?

Thanks,


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## brucek (Apr 11, 2006)

> corresponding digital in/digital out connections from preamp, acting like a digital "tape loop


I don't ever recall seeing such a thing.

brucek


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## spreston (May 21, 2008)

Strange; seems such a waste not to make DA conversion fully available to enduser. 

Could that be possibly related to digital rights protection of CDs and DVDs?


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## brucek (Apr 11, 2006)

> Strange; seems such a waste not to make DA conversion fully available to enduser


Think about what you're asking them to do.

All the digital SPDIF inputs to a processor are sent to a switcher and then decoded (PCM, DTS, AC-3, etc) and processed into their respective types and multi-channels. All these digital channels (7?) are then finally sent to DACs to turn them into analog for further level control and output.

You want the manufacturer to _break out_ all those digital signals before the DAC's and process them through SPDIF transmitters and make them avalable as output jacks in SPDIF, and then provide the same number of digital loop inputs that require converting from SPDIF so the DAC's can receive the signals.

I just don't know of any processor that offers that. It would have very limited appeal to most people, so they don't waste costs on that feature.

brucek


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## spreston (May 21, 2008)

I am thinking a bit simpler 2 channel functionality. 

Digital in/out would be useful for those with CD or DAT units which have both playback and record functions...


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## Wayne A. Pflughaupt (Apr 13, 2006)

The problem is that A/V receivers and processors with digital record loops for CDR or DAT don’t have them switched like the analog tape loops of old. So, you have no access to the loop for utilizing and inserting a global processor. You would only be processing the record loop itself, for the purposes of the digital recorder...

Regards,
Wayne


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## jcfergus (Jun 10, 2014)

I'm interested in doing the same thing, but I have separate preamp and amp, so I'm not dependent on a pre-out/main-in capability. The desire to use both digital and analog sources compounds the problem. 

Currently, my preamp is setup normally, with phono input and D-to-A occurring in the CD player and in an external DAC (from streaming source). The analog pre-out connects to the analog input of the DEQ2496, where it is digitized, equalized and converted back to analog which drives the power amp. Volume information is handled and passed through by the DEQ2496.

I tried using my DAC as a preamp, routing the digital output to the DEQ2496 and the analog output from DEQ driving the power amp. While the DAC has volume control functionality, that is either not provided at the digital out or the DEQ doesn't recognize it, so I got full volume to the input to the amp, fortunately, for less than a second. 

The goal is to keep the digital music in the digital domain until it needs to drive the power amp. Currently, this doesn't seem possible without having a cobbled-together system with inline volume control and the like. 

Jim


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