How do I know I need a new amp or to bi-amp?

[ryanosaur]

Well of course you have to increase cabinet size as you add drivers. If you have two drivers, then that doubles the VAS, and that means you have to double the cabinet size, if you add four then you have to quadruple it. The point is that although the cabinet size will increase, the F3 won't using the same drivers. However sensitivity will increase which is the major gain. This occurs not only because of the addition, but also the impedance drop.
So two 8 ohm drivers in parallel will give you 6db more sensitivity over one. That is 3db for halving the impedance and 3db from the proximity driver coupling. That is just another illustration of Hoffman's iron man's law.

Mark, can a Driver be designed to have a smaller Vas?
Presumably, such a Driver would also have a higher Fs. What about Sensitivity, would that suffer with such an intentional design choice?

 

[TLS Guy]

Mark, can a Driver be designed to have a smaller Vas?
Presumably, such a Driver would also have a higher Fs. What about Sensitivity, would that suffer with such an intentional design choice?

The Vas is the equivalent volume of the speaker. What this means is that the speaker requires a volume of air with the same compliance as a weighted spring. That is why Vas id specified as a volume.

So lets take the spring. If you increase the weight on the spring it will oscillate at a lower frequency. If you make the spring looser, which means also more complaint then it will also oscillate slower. The reverse of the above will up the resonant frequency.

So, if you make the cone heavier, and or, make the suspension more compliant you will lower Fs. But a heavy cone means loss of efficiency, and a higher volume of air also lowers frequency. So the iron law holds.

So what you were asking is not solvable with current passive designs. For one thing, a sealed box still always has a box resonance, and this contributes to lower frequency ripple which is audible, and not really controllable with a passive design.

However with active designs and DSP, then far more is possible. You see the trend to small boxes and F3 at around 100 Hz, coupled to a matching sub.

This allows for much greater spl. and efficiency as there are no passive losses. Active crossovers with DSP are more accurate than passive ones, and allow for time correction which passives can not.

So it is no wonder these new speakers designed with these principals are getting rave reviews. However, the electronics must be made to the quality standards of car audio, and spares be available for the long term. If these speakers only have the reliability of receivers people will be very upset.

The other downside is sub localization. However in my view placing subs around the room is WRONG. As I have said many times, separating fundamentals from their harmonics is a bad thing. For movie mixes and the highly artificial pop culture, it is not of any great concern. For classical and instrumental music it is not good.

This move will be a huge advantage in home HT, as speakers will be small and very powerful as these new designs are. So this will garner much better social acceptance (WAF).

In my designs I have been moving in this direction for nearly 50 years. In my fronts they are active except for the high pass. Twenty years ago, there where no small low powered class D amps. There are now. So if I were designing now, it would be fully active. Active designs do not need large expensive inductors and caps. When I modified my Shure SR 106 crossover, to give the slopes and changing orders I wanted, the components cost cents. I could also do what could not be done with passive crossovers.

My speakers are essentially active speakers with tightly integrated subs. Which leads me to the last point that going forward speakers need to be installed and closely integrated with their subs. Sigberg Audio are correct to go down this road.

With this approach the improvement is SQ for the masses at reasonable cost will be beyond what most of you can envision. So at a cost many will be able afford, you will be able to enjoy better performance than a huge costly Perlisten, which is yesterday's design, and still not have to file for divorce.

 

[ryanosaur]

The Vas is the equivalent volume of the speaker. What this means is that the speaker requires a volume of air with the same compliance as a weighted spring. That is why Vas id specified as a volume.

So lets take the spring. If you increase the weight on the spring it will oscillate at a lower frequency. If you make the spring looser, which means also more complaint then it will also oscillate slower. The reverse of the above will up the resonant frequency.

So, if you make the cone heavier, and or, make the suspension more compliant you will lower Fs. But a heavy cone means loss of efficiency, and a higher volume of air also lowers frequency. So the iron law holds.

So what you were asking is not solvable with current passive designs. For one thing, a sealed box still always has a box resonance, and this contributes to lower frequency ripple which is audible, and not really controllable with a passive design.

However with active designs and DSP, then far more is possible. You see the trend to small boxes and F3 at around 100 Hz, coupled to a matching sub.

This allows for much greater spl. and efficiency as there are no passive losses. Active crossovers with DSP are more accurate than passive ones, and allow for time correction which passives can not.

So it is no wonder these new speakers designed with these principals are getting rave reviews. However, the electronics must be made to the quality standards of car audio, and spares be available for the long term. If these speakers only have the reliability of receivers people will be very upset.

The other downside is sub localization. However in my view placing subs around the room is WRONG. As I have said many times, separating fundamentals from their harmonics is a bad thing. For movie mixes and the highly artificial pop culture, it is not of any great concern. For classical and instrumental music it is not good.

This move will be a huge advantage in home HT, as speakers will be small and very powerful as these new designs are. So this will garner much better social acceptance (WAF).

In my designs I have been moving in this direction for nearly 50 years. In my fronts they are active except for the high pass. Twenty years ago, there where no small low powered class D amps. There are now. So if I were designing now, it would be fully active. Active designs do not need large expensive inductors and caps. When I modified my Shure SR 106 crossover, to give the slopes and changing orders I wanted, the components cost cents. I could also do what could not be done with passive crossovers.

My speakers are essentially active speakers with tightly integrated subs. Which leads me to the last point that going forward speakers need to be installed and closely integrated with their subs. Sigberg Audio are correct to go down this road.

With this approach the improvement is SQ for the masses at reasonable cost will be beyond what most of you can envision. So at a cost many will be able afford, you will be able to enjoy better performance than a huge costly Perlisten, which is yesterday's design, and still not have to file for divorce.

I knew i was asking the question from a clumsy perspective. I think I got it though, now. Thank you.

 

[Sawtaytoes]

Just to confirm I understood the power draw, these Polk Reserve R700 speakers are only using 7W of power each in my home theater and 1-2W from my PC? And only when listening at reference levels?

 

[lovinthehd]

Just to confirm I understood the power draw, these Polk Reserve R700 speakers are only using 7W of power each in my home theater and 1-2W from my PC? And only when listening at reference levels?

Well, if listening at -10 on the reference scale and that's matching up to 75dB average levels the average power at 10 ft is within that range. Nearfield would be less of course. Those aren't reference levels, tho (that would be 0 on the reference scale and would take 10x the power)....peaks from average can be up to 20dB more, which is 100x power, tho.

 

[PENG]

Just to confirm I understood the power draw, these Polk Reserve R700 speakers are only using 7W of power each in my home theater and 1-2W from my PC? And only when listening at reference levels?

Did you use the linked calculator? I entered your Polk's 88 dB sensitivity and got the following results:

So if you sit from 13 feet, 1 W should get you about 76 dB SPL, and for music listening that is loud enough for a lot of people especially considering in the following calculation, room gain is ignored and only 1 speaker is making sound. So for stereo listening, with the speaker near a wall, you would probably get closer to 80 to 82 dB and that would be quite loud.

Entering the correct distance is necessary though as every time you double the distance you will lose about 6 dB of SPL (assuming no room gain).

 

[Sawtaytoes]

The sensitivity was 89dB based on the Audioholics article, but that means it'd take even less power.

If I'm understanding correctly, I only need 1W of power for these speakers to get roughly reference levels of playback in my home theater. Why would I need an amp providing more than 200W/ch?

Are there that many people using speakers with super low sensitivity? I've always bought Polk, so I'm not sure what to expect. I did buy some Revels months before getting the Reserve R700s, but returned them after a few weeks. I didn't do any SPL meter stuff back then, but those Revels were easily driven at a normal listening volume from the 2006 Yamaha receiver I was using at the time.

If most people can run their speakers at 1W, I don't get why you'd need much more power; it doesn't make sense. Jean always talks about how newer receivers have more channels for Atmos, but less power available overall compared to older receivers. Based on these calculations, it doesn't look like you'd need much power per channel at all. A 40W amp in the receiver should be enough for an entire Atmos setup.

 

[AcuDefTechGuy]

If I'm understanding correctly, I only need 1W of power for these speakers to get roughly reference levels of playback in my home theater.

No. not “REFERENCE“ THX levels, which is 85dB AVERAGE and 105dB PEAK for a loudspeaker.

The 1W is to to produce about 76dB Volume, which is “LOUD ENOUGH” for many people.

 

[lovinthehd]

The sensitivity was 89dB based on the Audioholics article, but that means it'd take even less power.

If I'm understanding correctly, I only need 1W of power for these speakers to get roughly reference levels of playback in my home theater. Why would I need an amp providing more than 200W/ch?

Are there that many people using speakers with super low sensitivity? I've always bought Polk, so I'm not sure what to expect. I did buy some Revels months before getting the Reserve R700s, but returned them after a few weeks. I didn't do any SPL meter stuff back then, but those Revels were easily driven at a normal listening volume from the 2006 Yamaha receiver I was using at the time.

If most people can run their speakers at 1W, I don't get why you'd need much more power; it doesn't make sense. Jean always talks about how newer receivers have more channels for Atmos, but less power available overall compared to older receivers. Based on these calculations, it doesn't look like you'd need much power per channel at all. A 40W amp in the receiver should be enough for an entire Atmos setup.

Because you want an amp for more than an average level generally, need to allow headroom for peaks. The THX standard as mentioned (for movies) is 85dB average level (at your seat) with allowance for peaks of up to 20 dB (100x the power). So a 200wpc amp isn't all that unusual if listening at higher levels, or at longer distances from the speakers, etc.

 

[Swerd]

If most people can run their speakers at 1W, I don't get why you'd need much more power; it doesn't make sense. Jean always talks about how newer receivers have more channels for Atmos, but less power available overall compared to older receivers. Based on these calculations, it doesn't look like you'd need much power per channel at all. A 40W amp in the receiver should be enough for an entire Atmos setup.

Music is almost never at a constant loudness. It varies widely from moment to moment. So, it can be hard to predict exactly how much power you need to drive your speakers.

What's more, the relationship between Power (in Watts) and loudness (in dB) if you graph it, is not a simple linear curve, its a logarithmic curve. In the curve below, if you get quieter (moving from left to right), it takes less and less power. But those changes are much bigger than if the relationship was linear. A drop in power by half results in a 3 dB loss in loudness, where a change of ±1 dB is roughly the smallest change most people can hear. And, a drop of 6-10 dB in loudness is perceived by humans as half as loud.

 

[fmw]

How do I know I need a new amp or to bi-amp?
More importantly how do you know you want a new amp or to bi-amp. Lower frequencies require more current (hence more watts) than higher frequencies. The first thing you do is deal with the lower frequencies. The solution is a subwoofer or two or however many you think you want. If you have done the subwoofer(s) right then the rest is trivial. It is unlikely that you would use more than 10 or 20 watts per speaker given the high sensitivity of your chosen speakers. So, assuming you took care of the low frequencies, you don't need a new amp or any bi-amplification at all. Whatever you have will do just fine.

Now when we get to what you want, I can't help you. That is up to you. You are entering into a crazy world that is audiophilia. I was addicted to it for quite a while and worked hard to wean myself from it. It was an incredibly expensive pursuit. Audiophilia isn't about music or movie soundtracks or even entertainment. It is about equipment. It is a bottomless pit. You only need to read the posts on this forum to understand that.

Set it up and enjoy it. It is really meant for entertainment. Let it entertain you.

 

[Sawtaytoes]

How do I know I need a new amp or to bi-amp?
More importantly how do you know you want a new amp or to bi-amp. Lower frequencies require more current (hence more watts) than higher frequencies. The first thing you do is deal with the lower frequencies. The solution is a subwoofer or two or however many you think you want. If you have done the subwoofer(s) right then the rest is trivial. It is unlikely that you would use more than 10 or 20 watts per speaker given the high sensitivity of your chosen speakers. So, assuming you took care of the low frequencies, you don't need a new amp or any bi-amplification at all. Whatever you have will do just fine.

Yep, both my PC and home theaters have subs! I couldn't imagine not having one. I'd be missing a huge chunk of the audio.

 

[fmw]

Yep, both my PC and home theaters have subs! I couldn't imagine not having one. I'd be missing a huge chunk of the audio.

Excellent. I even have a sub on my business computer in the office and another one in the bedroom and another one in the exercise room. Did I mention the home theater? Happy listening.

 

[highfigh]

You've fallen in to the trap many do. I spent a lot of time researching bi-amping. Here's the kicker:
4 out of 5 boutique Speaker Designers said it's pointless. 1 Speaker designer thought it was pointless, but though bi-wiring was effective.

The thing is, you were answered, just not the way you wanted.
Speaker sensitivity will tell you how much power (usually 2.83v) is required to achieve a certain dB level at 1 meter. Shady measured the R700s at 89dB sensitivity and a nominal 6-ohm impedance. The impedance minima doesn't look like it dips below 5ohms in his measurements, and the worst phase angle does not coincide with that impedance minima.
In short, and as Shady reported: these are not a difficult load to drive.
Your Amp, in the Monolith, has more than enough power to handle them. You do not need more power.
But since you insist on asking... your Amp will deliver between 250w and 300w of power (maxed out) to your Speaker and it should produce approximately 113dB of output at 1m.
To be certain: this is an unhealthy SPL level that can produce hearing damage at sustained levels.
Again, you do not need more power.

Now... you make an assumption above that bi-amping will deliver more power to the Speakers.
This is not true.
The amount of power sent to the LF and HF sections of the XO... IS NOT ADDITIVE. The LF and HF sections of the passive XO network built into the Speaker will still see the same amount of power as they would if you just run the wiring conventionally, which is to say a single cable to a single pair of Binding Posts with the Jumper Bars in place.

Bi-amping is not bad. It just does not really do what everybody insists it does. At best, each Amp channel involved will see a different load (so to speak) but this will not result in a difference in SQ.
Perhaps if you had a much more demanding Bass section on your Speakers that required much more current at a severe phase angle, this could result in an audible difference, but you would likely need a more robust amplifier in that specific use case.
That being said, if you really just want to do it, go for it. Just do it properly, and no harm should befall your equipment. However, if you mess something up, you can quite possibly blow your Amp and Speakers both.
This is not meant to be a scare tactic: simply a warning.

Another issue: 8" Woofers? So what.
I have 8" Woofers in my Speakers. They don't require anything special.
My Subs are 13" Woofers. They have their own Amps. I am building 15" Subs. They will require more Power than my other Subs, but learning a little aboiut how these things work isn't difficult.
There are Speakers out there that use 10" and 12" Drivers that are not designed to be used as Subwoofers.
Subwoofers are a specific beast, but the usage is bastardized. I've see 4" Subwoofer Drivers on the market, and they should never be called "Subwoofer Drivers."

There is a lot to learn if you really want to get to know how Speakers and Amps operate. There are a lot of great resources here at AH and in other Forums and Web articles that can help you learn. Likewise, there are a lot of very knowledgeable cats her and at the other Audio Forums who will gladly help you learn more, as well. The caveat there is to not pretend that you know more than you do.

Please rest assured in knowing that your Monolith and R700s are a good match and will serve you well.

Cheers.

As I have posted several times, dual pairs of binding posts appeared in the early-'80s after the audio rags started talking about separating the frequency bands and after a couple of "high end" speaker cable manufacturers began to sell cable with two pairs of conductors. Not wanting to be left out of the fad, speaker manufacturers followed like sheep. People who hadn't heard of this wanted to be seen as 'I know things', so they bought it hook,line and sinker. They often came into the store asking "How many amps does this receiver put out?", but they knew all about speaker wire.

 

[highfigh]

Yep, both my PC and home theaters have subs! I couldn't imagine not having one. I'd be missing a huge chunk of the audio.

Computer speakers couldn't produce bass if they wanted and most home theater speakers are designed specifically to NOT produce it, because they're rarely packaged as a set without a sub. The speaker manufacturers make a lot more money when they sell subwoofers.

 

[mono-bloc]

As I have posted several times, dual pairs of binding posts appeared in the early-'80s after the audio rags started talking about separating the frequency bands and after a couple of "high end" speaker cable manufacturers began to sell cable with two pairs of conductors. Not wanting to be left out of the fad, speaker manufacturers followed like sheep

Actually your not quite correct, quite a few high end designs only come with a single set of speaker connections. The like of Wilson, Magico, Rockport, Kharma, YG. And of cause Gryphon. Some come with a fully sealed section in the base of the speaker to hold the crossover units Also some of the larger models such as MBL, and Gryphon Pendragon come with a independent powered external crossover. And you won't find anything more high end on the planet. The idea of duel speaker connections comes with the idea of by-amp configurations, Which is completely meaningless except it has that selling point. And it also allows the fancy speaker cable manufacturers to sell more over priced cables

 

[StephenHernandez]

I don't know about that.

 

[highfigh]

Since we're already drinking, here's the Audioholics article on bi-amping / bi-wiring https://www.audioholics.com/frequent-questions/the-difference-between-biamping-vs-biwiring

As to subs, most of us look to response down to 20hz or better to be a true sub, I can't think of any 8" subs that can do that at a reasonable spl or distortion level.

ps For your desktop/nearfield use just how loud are you listening ?

This loud?

 

[highfigh]

Actually your not quite correct, quite a few high end designs only come with a single set of speaker connections. The like of Wilson, Magico, Rockport, Kharma, YG. And of cause Gryphon. Some come with a fully sealed section in the base of the speaker to hold the crossover units Also some of the larger models such as MBL, and Gryphon Pendragon come with a independent powered external crossover. And you won't find anything more high end on the planet. The idea of duel speaker connections comes with the idea of by-amp configurations, Which is completely meaningless except it has that selling point. And it also allows the fancy speaker cable manufacturers to sell more over priced cables

How am I wrong? They use one pair of terminals, now, sure- I commented on when this BS started. Gryphon, as an audio company, didn't exist until 1985, after the dual binding post trend began. I don't know when MBL started, but I never saw anything from them until relatively recently (the last 20 years. or so)- they certainly weren't selling speakers in the US when this BS began to pollute peoples' minds.

We're not talking about 'ultimate high end' and all of the brands you showed are on the fringe, not mainstream.

There were almost no 'fancy speaker cable manufacturers' in the early-'80s and the speaker manufacturers didn't start to cross-advertise until later.