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Signal path question: Tube amps with powered (solid state) subwoofers.

Ohighway

Ohighway

Wannabe Minimalist
Subscriber
A little question I've been pondering.

Let's say you're running a tube integrated amp or tube pre/power amps. If you add a powered (solid state amp) subwoofer to the system, does the tube amp signal just pass "straight through" the subwoofer power amp to the speakers, or does it pass through solid state components before reaching the speakers?
 
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Ohighway said:
Nobody with any input or opinion on this? Or did I botch the question?
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Well, the signal from the tube pre would be passing through it (since you're connecting the pre to the sub).

I assume you're using a pre with a sub output? If you're connecting an integrated, only the pre signal goes out to the speakers OR the sub. It depends on the system. If you're bi/tri-amping, then that would be different.
 
Ok, I botched the question.

I'm talking about a sub with SS amp that uses speaker level inputs. If I feed the tube amp speaker level output to the the speaker level inputs on a SS sub amp, do those signals pass through 'uncorrupted' so to speak? Or do they pass through a whole slew of SS components.
 
the tube amp is not providing the power for the sub, only the signal for the sub amp. the speaker-level inputs are for when it's not convenient to use an RCA cable for the signal.
 
Tube amp-->line input on sub-->speakers

To some degree, it simply can not be as good as a direct connection. Would you cut your speaker wires in half, splice them back together and call them the same as before?

I had my powered sub connected this way for a short while. Not anymore.

Sub is good for movies, not so good for music.

Polk 3 way M70's
Polk 12" sub
 
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Sometimes there's a crossover in the subwoofer, so it cuts the lows going to the speakers and sends them only to the sub. In that case, the speaker signal is going through additional components in the subwoofer, though they are probably passive (caps, resistors, and inductors) and not any solid-state active components.
 
I also felt there was slight latency between the powered sub and speakers. It is just not plausible that the powered sub and speakers could be in 100% sync. So to avoid any doubts, my theory was all speakers must be powered by the same amp. And it sounds great without the sub.

Which is why I prefer mono over stereo over surround sound.

Any is probably why I think electrostatic speakers sound so good. Timing accuracy.
 
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Tuxman said:
I felt the sub didn't match up to the music very well, caused by the slight latency between the sub and the speakers.
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does your sub amp have a phase control? playing around with that can help the sub output match the speaker much better. and also make sure you don't have the sub turned up too much, and that you have the low-pass point set to the low end of the speaker response. you don't want it to sound like a separate entity, and that can be tricky to achieve.

but there isn't any extra "latency" caused by using either the RCA's or high-level inputs, just so we're clear on that.
 
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I understand and set phase control, volume control, and cross over control to my liking. It was when I removed the sub I found the sound I liked best.

YMMV

Latency aka delay. It's there, but is negligible. (quantities so small that they can be ignored)

Dang, latency why you still exsist?

http://en.wikipedia.org/wiki/Latency_(audio)
 
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Tuxman said:
I understand and set phase control, volume control, and cross over control to my liking. It was when I removed the sub I found the sound I liked best.
Click to expand...

you're definitely not alone.

Latency aka delay. It's there, but is negligible. (quantities so small that they can be ignored)

Dang, latency why you still exsist?
Click to expand...

so you do or don't think your integration problem is latency?
 
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I felt the audio didn't match up. The speakers get the signal at the same time the powered sub does. But the sub still has to route the signal though it's SS amplifier before reaching the sub-woofer.

Just talking milli-seconds for that to happen. I read all I could about sound engineering and believe it's latency (delay) that I am picking up on.
 
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The inherrent maximum delay in such systems is in the area of a couple of micro seconds, not milli seconds.

That kind of signal delay is inaudible. What you're hearing and interpreting as signal daley is most likely phase differences and incorrect sub woofer settings.

In my experience almost every instance of poor integration between a sub and main speakers is because the sub is playing too loud and the crossover frequency is too high.

If you can hear the sub as being on it's almost certainly too loud.
 
the crossover will have some group delay, but audibility seems to be a bit questionable, depending on what you read. where was your sub positioned compared to the speakers?
 
Sub positioned center. Speakers 10ft apart. 1 ft from back wall.

The sub could be overdriving the bass due to the hardwood floors causing a muddy sound I preceive as delay?

so turn the power down eh?
 
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