External DAC with Integrated Amp

[antanast]

Hi guys. Can someone explain to how this works, as I am confused.

I have an external DAC (ADI DAC 2 FS) connected to my Integrated Amp (Rotel A11 Tribute). The DAC plays in most cases from my PC (Roon). To my understanding, the DAC's purpose is to convert Digital to Analog. But since the DAC connects to the A11 which is an integrated AMP, doesn't the A11 also use its internal DAC, which then defeats the purpose of having an external DAC or did I get something wrong? In other words, can you have the external DAC the only DAC working in the chain with the integrated AMP?

Thanks alot!

 

[Dunring]

It mentions that has Bluetooth for an input, which would need a DAC chip. For the cable inputs, it would go by an analog signal from your external DAC. Some other models like from SMSL has that feature, but the DAC portion only works on the Bluetooth input.

 

[antanast]

It mentions that has Bluetooth for an input, which would need a DAC chip. For the cable inputs, it would go by an analog signal from your external DAC. Some other models like from SMSL has that feature, but the DAC portion only works on the Bluetooth input.

So you mean that A11 only uses it's internal DAC for bluetooth connection?

 

[audio_tony]

The Bluetooth module probably has it's own on board DAC and therefore none of the other inputs would be using the DAC.

There are no digital inputs on this amp, so therefore no access to the Bluetooth DAC.

It's exactly as @Dunring says.

 

[antanast]

Thanks @audio_tony and @Dunring !

 

[Overseas]

A11 Tribute is excellent but has no DAC except for BT connection, which audibly seens very nice (Aptx hd connection).

 

[staticV3]

@antanast By default, the A11 Tribute's analog inputs bypass the built-in DAC and go straight to the Amp.

However, as soon as you switch the Tone Control from BYPASS to any other option (ENABLED/ROTEL BOOST/ROTEL MAX), the A11 Tribute's analog inputs get digitized, processed, converted by the built-in DAC, and then sent to the Amp.

 

[audio_tony]

@antanast By default, the A11 Tribute's analog inputs bypass the built-in DAC and go straight to the Amp.

However, as soon as you switch the Tone Control from BYPASS to any other option (ENABLED/ROTEL BOOST/ROTEL MAX), the A11 Tribute's analog inputs get digitized, processed, converted by the built-in DAC, and then sent to the Amp.

Are you sure about that?

There's no mention of an ADC (which is what would be required based on your comment).

All the info I can find suggests the amp is pure analogue apart from the Bluetooth component.

 

[staticV3]

Are you sure about that?

There's no mention of an ADC (which is what would be required based on your comment).

All the info I can find suggests the amp is pure analogue apart from the Bluetooth component.

Can't do remote-controlled EQ presets and Bass/Treble control in 1dB steps without digitizing the signal first.

So yes.

Edit:
Well, to be fair, it is physically possible to implement those features in analog.
But a manufacturer would have to be out of their mind to seriously pursue that.
Cost and complexity would shoot through the roof.

 

[antanast]

@antanast By default, the A11 Tribute's analog inputs bypass the built-in DAC and go straight to the Amp.

However, as soon as you switch the Tone Control from BYPASS to any other option (ENABLED/ROTEL BOOST/ROTEL MAX), the A11 Tribute's analog inputs get digitized, processed, converted by the built-in DAC, and then sent to the Amp.

So that means, that if you switch the tone control from BYPASS to another option and you have an external DAC connected, you are basically using once the external DAC, then a second time with the DAC of the A11?

 

[staticV3]

So that means, that if you switch the tone control from BYPASS to another option and you have an external DAC connected, you are basically using once the external DAC, then a second time with the DAC of the A11?

Correct.
Digital source->DAC->[ ADC->DSP->DAC->Amp ]->Speakers.

[ Rotel A11 Tribute ]

 

[audio_tony]

Can't do remote-controlled EQ presets and Bass/Treble control in 1dB steps without digitizing the signal first.

So yes.

Edit:
Well, to be fair, it is physically possible to implement those features in analog.
But a manufacturer would have to be out of their mind to seriously pursue that.
Cost and complexity would shoot through the roof.

I beg to differ with you.

From the HiFi News review:
The A11 Tribute amplifier, like the model on which it’s based, is something of a curiosity – it’s basically an all-analogue design, with MM phono and four line-ins, albeit also hosting a Bluetooth receiver on the rear panel, feeding another self-contained Texas Instruments 192kHz/24-bit DAC. However, that’s all the DAC does, with this 50W-rated amplifier keeping the rest of its signal paths relatively simple.

No digital tone controls. All analogue.

It's easy with current chips to implement electronic tone controls with 1dB steps.

Chips like the TDA7440 (albeit 2dB steps with that one) - no DAC here.

Link to review: https://www.rotel.com/sites/default/files/HFN Jan Rotel CD11-A11 Tribute_Reprint.pdf

 

[audio_tony]

Correct.
Digital source->DAC->ADC->DSP->DAC->Amp->Speakers.

I'm sorry, but you are wrong! See my post above.

There is no ADC in this amp!

 

[staticV3]

I beg to differ with you.

From the HiFi News review:
The A11 Tribute amplifier, like the model on which it’s based, is something of a curiosity – it’s basically an all-analogue design, with MM phono and four line-ins, albeit also hosting a Bluetooth receiver on the rear panel, feeding another self-contained Texas Instruments 192kHz/24-bit DAC. However, that’s all the DAC does, with this 50W-rated amplifier keeping the rest of its signal paths relatively simple.

No digital tone controls. All analogue.

It's easy with current chips to implement electronic tone controls with 1dB steps.

Chips like the TDA7440 (albeit 2dB steps with that one) - no DAC here.

View attachment 368564

Link to review: https://www.rotel.com/sites/default/files/HFN Jan Rotel CD11-A11 Tribute_Reprint.pdf

Thanks for the correction!

 

[audio_tony]

So that means, that if you switch the tone control from BYPASS to another option and you have an external DAC connected, you are basically using once the external DAC, then a second time with the DAC of the A11?

No. I explained it all above.