mini-X to power rear surrounds?

[kse]

So I bought a mini-X to ultimately be used as part of a 2ch rig I plan to assemble down the road. In the mean time, rather than leave it boxed up, I figured I'd put it to use.

My HT system is 7.1. My fronts, center and sides are all powered by Emo amps, the rears are powered by the receiver.

I am thinking of using the mini-X for the rears, my question is, how/where would I set the volume control on the mini-X?

Thanks.

[novisnick]

Oct 27, 2013 12:26:51 GMT -5 kse said:

So I bought a mini-X to ultimately be used as part of a 2ch rig I plan to assemble down the road. In the mean time, rather than leave it boxed up, I figured I'd put it to use.

My HT system is 7.1. My fronts, center and sides are all powered by Emo amps, the rears are powered by the receiver.

I am thinking of using the mini-X for the rears, my question is, how/where would I set the volume control on the mini-X?

Thanks.

The rears should not be noticeable unless your watching a 7.1 incepted audio movie. There's a seine in the last 007 movie where a helicopter is moving through the room, the sound should be proportional  to your room.
just remembered the name,Sky Fall,
I have a good starting point with YOPL on my Yamaha AVR, then I adjust manually.
Hope this helps.
Peace,
Nick

[kse]

Oct 27, 2013 12:34:29 GMT -5 novisnick said:

Oct 27, 2013 12:26:51 GMT -5 kse said:

So I bought a mini-X to ultimately be used as part of a 2ch rig I plan to assemble down the road. In the mean time, rather than leave it boxed up, I figured I'd put it to use.

My HT system is 7.1. My fronts, center and sides are all powered by Emo amps, the rears are powered by the receiver.

I am thinking of using the mini-X for the rears, my question is, how/where would I set the volume control on the mini-X?

Thanks.

The rears should not be noticeable unless your watching a 7.1 incepted audio movie. There's a seine in the last 007 movie where a helicopter is moving through the room, the sound should be proportional  to your room.
just remembered the name,Sky Fall,
I have a good starting point with YOPL on my Yamaha AVR, then I adjust manually.
Hope this helps.
Peace,
Nick

Thanks for the input, but not sure I follow you...? With PLIIx the rears are always active regardless if audio mix is 5.1 or 7.1.

When you say, "YOPL", are you meaning YPAO? If so, yes, I understand this would need to be re-run with the introduction of the mini-X.

So, back to the original question, where would I set the volume on the mini-X?

[knucklehead]

All the way up.

[novisnick]

Start at max then, and if it's noticeably over bearing start to trim it down and yes to the YPAO.
Please let me know how the mini works in this capacity! I'm looking for the least expensive way out of accomplishing an almost identical problem.
I was looking at this route but I am undecided. Your response would be greatly appreciated.

Peace,

Nick

[GreenKiwi]

^^^ what he said.

I think the earlier comment was just generally saying that the receive is probably more than competent at driving 2 rear channels.

[kse]

Oct 27, 2013 12:54:26 GMT -5 GreenKiwi said:

I think the earlier comment was just generally saying that the receive is probably more than competent at driving 2 rear channels.

I don't disagree, but like I said, no reason to leave it boxed up.

[GreenKiwi]

Or get another set is speakers and start your second 2ch system early =P

I've though some tekton m lores would match nicely.

[jlafrenz]

I don't think I would max it out. I would probably leave it in the 50-75% range and then make sure all your channels are level matched. Turn the volume up/down and make sure they are still level matched.

[unsound]

I'm considering this exact same thing. Please let me know how your experiment turns out. One thing to keep in mind is that the mini-x only requires 600mv to reach max output. So depending on the output of your preamp and whether the volume control on the mini impacts the input gain or output gain you may not want to set it to full volume. I'm just learning about matching gain stages, so I could be wrong and would appreciate a correction if I am.

[Jim]

I could be wrong, but from what I've read the volume adjustments really don't change the gain. The amp is fixed gain. All it does is attenuate the input signal.

So, I'm in the "turn it all the way up" camp - and you can likely trim it enough in your AVR/processor. Most have very flexible levels.

[unsound]

Well, it doesn't change the internal gain of the amp,sure. But, if you consider the amp as 1 block of equipment, the volume control impacts the gain of that block. So, it either impacts the input stage or the output stage. If your amp takes a max signal of 600 mv and your preamp can output 2V, there is a possibility of overloading the input stage. If the volume control impacts the input stage, then it can be set to where 2V from the preamp is feeding 600 mV to the mini-X. At least, that's my understanding.

[Jim]

Oct 27, 2013 14:12:54 GMT -5 unsound said:

Well, it doesn't change the internal gain of the amp,sure. But, if you consider the amp as 1 block of equipment, the volume control impacts the gain of that block. So, it either impacts the input stage or the output stage. If your amp takes a max signal of 600 mv and your preamp can output 2V, there is a possibility of overloading the input stage. If the volume control impacts the input stage, then it can be set to where 2V from the preamp is feeding 600 mV to the mini-X. At least, that's my understanding.

On my Onkyo - I can change the level from super low levels up to very very high ones.

Kse- what processor/AVR are you using?

My thinking was as long as the level is adjustable enough, it seems silly to output a higher than necessary level - only to reduce it with the mini-x. Ideally you only want to change level settings in one place and not two.

[unsound]

You can set the volume of your Onkyo at a particular point, but the Voltage going to each channel also depends on the information being played through that channel. Setting the volume at a specific level doesn't mean everything coming out of your Onkyo will have the same loudness. If you have 2 different amps connected to the Onkyo and they're both 100W/ch but one amp takes 1 V to reach max output whereas the other one takes 2 V to reach max output, where will you be setting the volume? You'll have to control the volume by channel (through the channel level controls). So, it all can be done, of course, you just have to be careful when trying to use very different amps with the same preamp. This is one of the reasons some of the Emo amps have a gain control in the back - Emo used a 32dB gain where industry standard was more 29 dB.

[Jim]

Oct 27, 2013 14:20:22 GMT -5 unsound said:

You can set the volume of your Onkyo at a particular point, but the Voltage going to each channel also depends on the information being played through that channel. Setting the volume at a specific level doesn't mean everything coming out of your Onkyo will have the same loudness. If you have 2 different amps connected to the Onkyo and they're both 100W/ch but one amp takes 1 V to reach max output whereas the other one takes 2 V to reach max output, where will you be setting the volume? You'll have to control the volume by channel (through the channel level controls). So, it all can be done, of course, you just have to be careful when trying to use very different amps with the same preamp. This is one of the reasons some of the Emo amps have a gain control in the back - Emo used a 32dB gain where industry standard was more 29 dB.

I feel like I'm missing something. You set the channel levels because of differing speaker sensitivities, distances and potentially amp gains. Is there an issue I'm missing?

If you set a speaker with a 75db test tone - you're going to be raising or lowering the level (and in effect the max output level) that's sent to the amp.

I believe normally amps that have adjustable gain (like 29/32) are most often used by integrators -- because it can easily fix the gain mismatch - if other amps are being used. I don't think 29 is a standard as much as it's what THX specs.

I agree that an amp that's fully driven at 600mv is quite different than 1.2. So perhaps - you'd set the knob half way on the mini x - and that way you'd have similar AVR output level settings. But it shouldn't make any difference.

[unsound]

Oct 27, 2013 16:12:58 GMT -5 Jim said:

Oct 27, 2013 14:20:22 GMT -5 unsound said:

You can set the volume of your Onkyo at a particular point, but the Voltage going to each channel also depends on the information being played through that channel. Setting the volume at a specific level doesn't mean everything coming out of your Onkyo will have the same loudness. If you have 2 different amps connected to the Onkyo and they're both 100W/ch but one amp takes 1 V to reach max output whereas the other one takes 2 V to reach max output, where will you be setting the volume? You'll have to control the volume by channel (through the channel level controls). So, it all can be done, of course, you just have to be careful when trying to use very different amps with the same preamp. This is one of the reasons some of the Emo amps have a gain control in the back - Emo used a 32dB gain where industry standard was more 29 dB.

I feel like I'm missing something. You set the channel levels because of differing speaker sensitivities, distances and potentially amp gains. Is there an issue I'm missing?

If you set a speaker with a 75db test tone - you're going to be raising or lowering the level (and in effect the max output level) that's sent to the amp.

I believe normally amps that have adjustable gain (like 29/32) are most often used by integrators -- because it can easily fix the gain mismatch - if other amps are being used. I don't think 29 is a standard as much as it's what THX specs.

I agree that an amp that's fully driven at 600mv is quite different than 1.2. So perhaps - you'd set the knob half way on the mini x - and that way you'd have similar AVR output level settings. But it shouldn't make any difference.

Not sure I understand how you're setting the max output level to the amp with your test tone. Are saying that if I calibrate my speaker with 75 db test tone and then try to listen at 105db, there won't be any increase in the level sent to the amp? Edit: I understand what you're saying. Yes, you do affect (not set like I previously thought) the max output level by raising or lowering. But, there's no guarantee that you've lowered it enough for it not to go over 600 mV. You may want hear at louder volumes or you may be listening to something that's dynamic where the peak is significantly higher.

Are you saying it is no problem sending, say, 2v to the mini or are you saying that 2v will not be sent to the mini?

[Jim]

Well, so gain structure is quite fun. Clipping is just as much fun. 2v sent to the mini will clip it. I would think that if you use the onboard volume knob you COULD attenuate 2v down to a reasonable level that doesn't clip it. If you lower the channel volume ENOUGH, you can probably keep it below 600mv (but it's totally dependent on the AVR - as to how much you can trim it). So is it possible that the other channels could play 100db, and the Mini is on the verge of clipping? It's possible.

My experience with clipping has been interesting. I've managed to clip a couple sub amps, they're easier to clip because there are times when the signal hits 0dbfs --- and the THX standard expects 115db from the sub (which can be a big demand).

I've used MiniDSPs which have a .9 or 2v sensitivity, and you can tell what the signal input looks like and when you might be close to clipping the MiniDSP. Now, how to tell if you're potentially clipping an amp? That's hit or miss. From what I understand, generally using a multimeter and looking at the RMS voltage isn't very useful (but I believe with test tones it can work)....... so what you really need is an Oscilloscope to see what the real peaks are.

In my setup (in boxes at the moment!), I have plenty of overhead, so should never come close to clipping. You can learn a lot about your system by playing test tones and measuring the RMS voltage and changing the channel level output (and system volume) of the pre/pro.

What may seem like plenty of overhead can be little/nothing when you're at reference volume. It's A LOT more power.

I'm a big fan of this URL, as it can give you a pretty good idea of what wattage is needed for whatever sound level:
myhometheater.homestead.com/splcalculator.html

If anyone has any more insightful/useful ways of detecting clipping, I'm always interested. I want to buy an oscilloscope, but it's $$ and I wouldn't use it very often!

[garbulky]

Oct 27, 2013 16:49:48 GMT -5 unsound said:

Oct 27, 2013 16:12:58 GMT -5 Jim said:

I feel like I'm missing something. You set the channel levels because of differing speaker sensitivities, distances and potentially amp gains. Is there an issue I'm missing?

If you set a speaker with a 75db test tone - you're going to be raising or lowering the level (and in effect the max output level) that's sent to the amp.

I believe normally amps that have adjustable gain (like 29/32) are most often used by integrators -- because it can easily fix the gain mismatch - if other amps are being used. I don't think 29 is a standard as much as it's what THX specs.

I agree that an amp that's fully driven at 600mv is quite different than 1.2. So perhaps - you'd set the knob half way on the mini x - and that way you'd have similar AVR output level settings. But it shouldn't make any difference.

Not sure I understand how you're setting the max output level to the amp with your test tone. Are saying that if I calibrate my speaker with 75 db test tone and then try to listen at 105db, there won't be any increase in the level sent to the amp? Edit: I understand what you're saying. Yes, you do affect (not set like I previously thought) the max output level by raising or lowering. But, there's no guarantee that you've lowered it enough for it not to go over 600 mV. You may want hear at louder volumes or you may be listening to something that's dynamic where the peak is significantly higher.

Are you saying it is no problem sending, say, 2v to the mini or are you saying that 2v will not be sent to the mini?

You will not have a problem with input overload in real life.
If you adjust the volume via the mini-x then you can send the maximum volume of your reciever to it no problem. If you adjust the volume with the reciever (and set the mini-x at maximum) then you will still not be overloading anything. When your mini-x maxes out, then it will max out just like any piece of equipment. But you won't be encountering situations where you've set your reciever to a normal volume and the output spikes due to dynamic range and the mini-x badly distorts because it has gone over the 600mv limit - not in regular listening. It just doesn't happen. The mini-x has dynamic range and then some.

[Jim]

Oct 27, 2013 17:59:32 GMT -5 garbulky said:

Oct 27, 2013 16:49:48 GMT -5 unsound said:

Not sure I understand how you're setting the max output level to the amp with your test tone. Are saying that if I calibrate my speaker with 75 db test tone and then try to listen at 105db, there won't be any increase in the level sent to the amp? Edit: I understand what you're saying. Yes, you do affect (not set like I previously thought) the max output level by raising or lowering. But, there's no guarantee that you've lowered it enough for it not to go over 600 mV. You may want hear at louder volumes or you may be listening to something that's dynamic where the peak is significantly higher.

Are you saying it is no problem sending, say, 2v to the mini or are you saying that 2v will not be sent to the mini?

You will not have a problem with input overload in real life.
If you adjust the volume via the mini-x then you can send the maximum volume of your reciever to it no problem. If you adjust the volume with the reciever (and set the mini-x at maximum) then you will still not be overloading anything. When your mini-x maxes out, then it will max out just like any piece of equipment. But you won't be encountering situations where you've set your reciever to a normal volume and the output spikes due to dynamic range and the mini-x badly distorts because it has gone over the 600mv limit - not in regular listening. It just doesn't happen. The mini-x has dynamic range and then some.

But if you had low sensitivity speakers and were using the Mini-X and had it cranked up?

But yeah, realistically, surrounds just don't need the power 99% of the time.

I don't own a Mini-X, so I don't know how politely it handles over 600mv..

[unsound]

Oct 27, 2013 18:02:21 GMT -5 Jim said:

Oct 27, 2013 17:59:32 GMT -5 garbulky said:

You will not have a problem with input overload in real life.
If you adjust the volume via the mini-x then you can send the maximum volume of your reciever to it no problem. If you adjust the volume with the reciever (and set the mini-x at maximum) then you will still not be overloading anything. When your mini-x maxes out, then it will max out just like any piece of equipment. But you won't be encountering situations where you've set your reciever to a normal volume and the output spikes due to dynamic range and the mini-x badly distorts because it has gone over the 600mv limit - not in regular listening. It just doesn't happen. The mini-x has dynamic range and then some.

But if you had low sensitivity speakers and were using the Mini-X and had it cranked up?

But yeah, realistically, surrounds just don't need the power 99% of the time.

I don't own a Mini-X, so I don't know how politely it handles over 600mv..

Yes, in most situations, I imagine it would be fine. I don't know how big his room is and how far away he is from his rear surrounds or how sensitive they are. I just think it's something for the OP to be aware of, that's all. And, that, pretty much was the motivation for my initial post.