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Using a powered sub with my tube amp

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I'm very new to the tube amp thing so any help would be great. I just purchased a Yaqin MC-10l and I am going to build my own two way book shelf speakers. I would like to hook up my velodyne powered sub to the system for the bottom end. What is the best way to hook this up to the tube amp considering the amp does not have RCA audio outputs? The powered sub does have line level imputs. Would simply running a set of wires in parallel from the left and right amp channels to the bookshelfs and to the line level imputs of the subwoofer work, or would that have an effect on the impedance? How can I go about doing this?
 
Most subs have two input types: signal line level (using RCA connector) and speaker signal level (spring loaded or banana connector). It sounds like your sub can support either type. Also, most subs support speaker level signal out as well when it support speaker level signal in.

So if that is the case, you can use loudspeaker level signal into your sub and using the speaker level out to connect to the bookshelf speakers.
 
The best would be to use active crossover or bass management device which splits line level signal at given frequency and sends them to each respective output. This will require a master volume control such as the one in preamp. Many preamps come with bass redirect feature which will take care of your situation. Without it, you may have to resort to passive crossover which is not a good thing for sonic quality. In other words, you can build your bookshelf speaker but add a low pass filter to send it to the sub (not my personal preference).
 
The MC-10L is an intergrated amp. This set up is for my office and I wanted to keep it simple and avoid the preamp. The amp has three RCA inputs and no RCA audio out. Only left and right line level. Attached is a picture of the back of the sub. It's been so long since I've dug this one out I forgot that it has line level in and then has out to speakers. It also has RCA in and out. I guess I could go either way. I would imagine if I use the line in I would have volume control over the sub by using the volume on the tube amp. I could also go RCA in from source then out to the tube amp, but I would have to control volume at the sub. Any recomendations as to which is best. Also no one answered my original question. Would going parrallel out of the left and right line level of the tube amp and into both the speakers and the sub create a problem? Would that effect the load the amp is seeing?
 
The suggestion to use speaker level I/Ps on the SW is good, but "daisy chaining" is (IMO) ill advised. Let the main speakers play as close to full range as is possible. Connect the main speakers directly to the integrated amp via decent cables. Connect the SW's speaker level I/Ps to the integrated amp via 16 AWG OFC zip cord. Adjust the controls on the bass unit to fill in underneath the main speakers.

The arrangement described allows the SW to pick up the integrated amp's sonic signature, while avoiding the SW's crossover for most of the musical info.
 
I own the MC-10L as well but did not use with sub for the bottom as it has connected to a 3ways floor standing with good bass.

I do have the old HT amp which do not have the RCA sub output. Sub manual suggested daisy chain, amp o/p to sub, sub to L/R speakers. I've been on this setup since day one with good bass response.

Recently I shifted the HT amp position, re run the speaker cable. This time, I run additional pair for the sub so I have direct L/R speaker cable from the HT amp. Surprise, I loose almost half of the bass power as I previously had. I have yet to switch it back to original daisy chain to confirm.
 
More to add in using the speaker line-out from the sub to the bookshelf:

- You need to tune the low pass cross-over freq for the sub to your bookshelf speakers.

- May have to play with the 0/180 phase switch (I do not hear differences between the 0 versus 180 phase ;-)
 
Thanks for the replies. So although I didn't get a stright yes or no answer, based on some of the responses I would imagine I would have no problem running parrallel out of the left and right speaker level of the tube amp and into both the bookshelfs and the speaker level in of the powered sub. I would imagine this would be my best bet as it would avoid the SW crossover.

If anyone can answer this specific question it would be great. Does hooking it up in the manner above have any effect on the load that the amp is seeing?
 
Does hooking it up in the manner above have any effect on the load that the amp is seeing?

There is no appreciable effect. ;) The SW's crossover presents a relatively high impedance to the main amp, below the "corner" frequency. When impedances are connected in parallel, the lowest of the set tends to dominate, according to the Law that follows immediately.

1/Z NET = 1/Z1 + 1/Z2 ... + 1/Zn

If 8 Ohms and 80 Ohms are connected in parallel, the net is approx. 7.3 Ohms.
 
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