Mcintosh MA-7900 home theater bypass with subs - not doable?


I acquired the MA-7900 and would like to use it in HT bypass mode.  I have my front mains and two subs (via Pre Outs) hooked up to the Mcintosh.  I want the front speakers AND subs to work on HT bypass, but can only get the front mains to work.  The subs will not play in "Passthru" mode.  

Does anyone know a work around to this or is this just a product of the amps age?  My Anthem has HT bypass for subs and mains.  
dtximages

I don’t own the 7900 but you can do it with an external crossover. You could pull the bars in the back that connect the preamp section to the amp and insert it there. Out of the preamp to the crossover then back into the amp input. From the crossover then out to the subs and from the home theater processor into the subs at the same time. 
 

An active crossover like the JL audio CR1 will take both a 2ch preamp and home theater LFE at the same time. Something like a mini dsp might work too but I have not used one before. 

I think the preamp outputs will work. Have you thought about high level inputs to the subs and bypass EQ when listening in stereo?

Did this ever get resolved? If so how as I have a 7900 coming and hope to do the same….? Thank you

Yes that's my issue.. I did get the FRONT's to work.. The manual says nothing about a subwoofer so I was hoping there was a way to do it.  
I found this on page 27 of the MA-7900 owners manual:

Equalizer Bypass

Press the Front Panel EQ BYPASS Push-button to remove the MA7900 Equalizer Control Circuitry from the signal path for the currently selected Input Source. The LED above the EQ BYPASS Push-button will il- luminate. Refer to figure 50. The MA7900 remembers for each selected Input whether the Equalizer Control Circuitry is deactivated. To reactivate the Equalizer Control Circuitry for the currently selected Input Source press the EQ BYPASS Push-button.

Note: 1. The audio signal present at the RECORD OUT Jacks is unaffected by the Tone Circuitry.

2. The EQ BYPASS can also be accessed by the TRIM Function, refer to page 24.

AND, I also found this:

• PassThru Mode: The Automatic PassThru Mode allows the MA7900 to become part of a Multichannel Sound System for DVD-Audio, SACD and Home Theater Movies.


AND, please see page 19, etc. for more info:

Passthru

The MA7900 can be part of a Multichannel Sound System for SACD, DVD-Audio and Home Theater. The Right and Left FRONT Channels from an Audio/ Video Control Center or Surround Decoder can “Passthru” the Preamplifier Circuitry of the MA7900, and then on to the Power Amplifier Circuitry of the MA7900. The Setup Mode allows the activation of the Passthru Mode and the selection of the specified MA7900 Input Source. In the example below,

the Right and Left Front Channels from the Audio/ Video Control Center will be connected to the SRVR (Server) Input Jacks on the MA7900. Refer to page 10 for additional connection information.

Notes: 1. The Phono Input Connectors and Digital Input Connectors are not assignable as a Passthru Input.

2. If the Balanced Input Connectors are already reassigned to a given Input, they will not appear in the list of available Inputs for the Passthru Mode.

3. When one of the RCA Inputs is selected as a Passthru Input, it is advisable to remove it from the list of available Inputs by switching it Off. Refer to “Source Inputs Reassignment” starting on page 18.

1. Press and hold the INPUT CONTROL until the Front Panel Display indicates the Setup Mode is active. Then rotate the INPUT CONTROL and select the Setup Menu item “SETUP: PASSTHRU, Source: OFF”. Refer to figure 15.

Figure 15

2. Rotate the VOLUME Control until “SETUP: PASSTHRU, Source: SRVR<RCA> appears on the....please see the manual for more info.


The above says "The Right and Left FRONT Channels from an Audio/ Video Control Center or Surround Decoder can “Passthru” the Preamplifier Circuitry of the MA7900, and then on to the Power Amplifier Circuitry of the MA7900". THIS MIGHT BE YOUR PROBLEM.  I DO NOT KNOW.


As several others have posted above, please call McIntosh direct for assistance or a McIntosh retailer.




OK.  Got it.  I would try a McIntosh dealer or the factory.  There is a very helpful dealer in Ann Arbor, MI called Paragon Sight & Sound.  Ask for Matt.  He can assist over the phone and guide you in the right direction. Let me know how it works out.  Which Anthem do you have?  I have a Statement D3. Lastly, don't forget to make sure you have the latest firmware upgrades on both the Anthem and the McIntosh.
OK.  Got it.  I would try a McIntosh dealer or the factory.  There is a very helpful dealer in Ann Arbor, MI called Paragon Sight & Sound.  Ask for Matt.  He can assist over the phone and guide you in the right direction. Let me know how it works out.  Which Anthem do you have?  I have a Statement D3. Lastly, don't forget to make sure you have the latest firmware upgrades on both the Anthem and the McIntosh.
@woots yes it mentions regular passthru which I'm currently and successfully using for the front 2 channels only.  I cannot get the subs to work on Passthru which are connected to the MA-7900 Pre Outs.
I saw that there were 2 mentions in the owners manual on pages 5 and 20.  Not sure if that helps but am curious if you have the latest firmware upgrade? I have mostly McIntosh equipment and would reach out to a local dealer or the company headquarters and they will point you in the right direction.  
Hope this helps.