[KTS]

Good morning,
I have been experimenting with different amps, primarily class A. I have noticed a large difference between amps on my OB subs. I have the RCA’s connected from the subs to a Freya + pre amp. My question is, how does the amp impact the pre-amp to impact the subs when the subs are not connected to the amp? Is the due to the impedance relationship of the amp and pre amp?

Thank you, Kelly

[emailtim]

Are you sure it is the sub and not a level match change caused by swapping amps on the mains ?

Are you measuring the subs before/after the swaps to see what is going on ?

[emailtim]

Another question. 

What mode are you running your Freya+ in ? 

There appears to be a big difference between Freya+'s pass through, SS and tube modes.

[Tyson]

A lot of the bass harmonics are coming through the main speakers, that's probably why you are hearing a difference.

[KTS]

Are you sure it is the sub and not a level match change caused by swapping amps on the mains ?

Are you measuring the subs before/after the swaps to see what is going on ?

I am not measuring the subs, I do not have the tools for that. I am not sure I understand level match, I do understand that increasing the volume on the pre amp will increase the output of the sub. I turn down the volume on the sub to match the SPL’s coming out of NX studios, by ear.

[KTS]

Another question. 

What mode are you running your Freya+ in ? 

There appears to be a big difference between Freya+'s pass through, SS and tube modes.

Tube mode- I will check to see if the difference is the same on unity gain.

Tyson you might be correct, I know how to check that pretty easy.

Thank you everyone for the responses.

[KTS]

A lot of the bass harmonics are coming through the main speakers, that's probably why you are hearing a difference.

It was a combination of the difference in the topology of the difference amps on my main speakers and my I lack of ability to level match the SPL by ear. When I turned off the subs the difference was apparent. Also running the preamp in SS as emailtim suggested the differences were not as obvious, so the gain was impactful. Thank you everyone for all the suggestions and help. It was not an issue, but to have a better understanding of the impact of the amp on the over all sound and not get fooled. Such a fun hobby!

Kelly