This week, we reviewed the Logitech Harmony Remote:

http://www.logitech.com/en-us/product/harmony-ultimate

There are some quirks, a few things we’d love to see improved – pretty much entirely on the software and programming side – but overall, we really love what the Harmony Ultimate offers, and we’re super impressed with it.

If you can afford its $350 price tag, we definitely recommend it highly.

AV Rant Listener Toby H. —

bought himself a new AV Receiver (congrats!)

But that means saying goodbye to his old Receiver that allowed him to connect two pairs of Surround speakers (Surround A and Surround B) and easily switch between them inside the AV Receiver so that one pair could be positioned and used for 5.1 music while the second pair could be positioned and used for movies and TV.

That connection scheme didn’t stick around very long as crowded AV Receiver back panels gave way to height, zone, and now Atmos speaker connection. But some folks would still like to be able to have one pair of Surround speakers for music, and a second pair of Surround speakers for movies.

It isn’t a perfect solution – you’ll have to carefully consider things like EQ, level, and distance settings – but one way to at least keep everything physically connected is by using an external Speaker Selector Switch:

http://www.monoprice.com/Product?c_id=109&cp_id=10903&cs_id=1090305&p_id=9995&seq=1&format=2

This is also a great device to have around for when you want to audition speakers. With a Selector Switch, you can rapidly switch between 2 pairs of speakers for proper A-B comparisons without long pauses in between selecting which speakers are playing.

AV Rant Listener Jason S. —

We’ve been talking quite a bit about surround sound audio-only recordings lately. Especially any that are in 7.1 channels.

Jason found a 40 (!) disc collection over on Amazon. What makes this special is that it’s in the “Blu-ray Audio” format using DTS-HD Master Audio in 7.1 channels. That means almost any Blu-ray player will be able to play this back; no need for a special SACD, DVD-Audio or multi-channel FLAC-capable player.

Check it out: http://www.amazon.com/Blu-ray-Signature-Classical-Collection-Updated/dp/B00JSDAW9Y/

AV Rant Listener David F. —

sent us a link to an article by author John Watkinson entitled “We need to talk about SPEAKERS: Sorry, ‘audiophiles’, only IT will break the sound barrier”.

http://www.theregister.co.uk/2014/07/02/feature_the_future_loudspeaker_design/

It’s a dense and lengthy article that covers a very large range of topics, but ultimately, we don’t agree with his conclusion that “legacy” speaker manufacturers will never change and that only IT companies can move speaker technology forward. One look at the sorts of things that companies like JBL, Phase Technology, Axiom Audio and others are doing today makes it pretty clear that “traditional” speaker manufacturers are advancing speaker technology in exactly the sorts of ways that John Watkinson describes.

But read through the article for yourself and let us know what you think in the comments below!

AV Rant Listener Eliezer —

heard the effects of a “Phase Inversion” switch on a high end Integrated Amplifier.

This is not a speaker polarity switch – it has nothing to do with the red and black speaker wire connections. No, this is about “absolute phase”, which is the notion of preserving the phase of the original signal all the way from the microphone to the loudspeaker. That’s essentially impossible if the signal has be edited, mixed, or adjusted in any way whatsoever. But nevertheless, some people believe it is important, and so this type of “Phase Inversion” switch exists on certain pieces of equipment.

If you would like to test whether you can hear the effects of “Absolute Phase” for yourself, there’s a nice blind test set up over at audiocheck.net just for that purpose:

http://www.audiocheck.net/blindtests_abspolarity.php

AV Rant Listener Eliezer —

made a list of some of the not-too-expensive external DACs (Digital to Analogue Converters) and headphone amplifiers that he has tried and recommends.

We’ve posted a few of these before, but just consider that confirmation from another avid user 🙂

Starting with desktop units:

– Schiit Audio Modi — $99 : http://schiit.com/products/modi

– Emotiva XDA-2 — $250 : https://emotiva.com/products/dacs/xda-2

– Peachtree DAC-it — $299 : http://www.peachtreeaudio.com/dac-it-digital-to-analog-converter.html

– Cambridge Audio DACMagic 100 — $299 : http://www.cambridgeaudio.com/products/hifi-and-home-cinema/dacmagic-100

—– And on the more portable side —–

– Audioquest Dragonfly — $150 : http://www.audioquest.com/usb_digital_analog_converter/dragonfly-dac

– iFi nano iDSD — $190 : http://ifi-audio.com/portfolio-view/nano-idsd/

– Cambridge Audio XS — $190 : http://www.cambridgeaudio.com/products/hifi-and-home-cinema/dacmagic-xs

– HRT Microstreamer — $200 : http://www.hirestech.com/product/?pid=107

AV Rant Listener Carlos C. —

is having a problem where his ceiling-mounted front projector vibrates whenever people in his house walk on the second floor above his theater room.

We wish we had a cheaper and easier solution to recommend to Carlos (and if you’re reading this and you know of something, please post it in the comments below!), but the only things that we could think of include beefing up the construction of his house so that the floors and ceiling joists no longer shake when people walk on them.

Tom had the good suggestion that Carlos’ current ceiling mount might not be screwed directly into a strong joist (perhaps it’s just screwed into the ceiling drywall or it’s a suspended ceiling). But if that isn’t the case, we’re back to a renovation being our top suggestion.

That said, using a shelf (suspended from the ceiling or attached to a nearby wall) rather than a ceiling mount might help – particularly if Carlos damps and decouples the projector from that shelf.

One way to do this is with IsoNodes: http://www.brightstaraudio.com/isonode.html

They’re definitely over-priced, and the claims made about them on Bright Star’s website are utterly ridiculous, but they do work quite well as easy-to-use damping feet.

Of course, another, much less expensive solution is good ol’ Blu-Tack, which you can get at pretty much any hardware or office supply store: http://www.blutack.com/

AV Rant Listener Jason A. —

wanted an easy way to calculate how many Watts of amplifier power he will need in order to reach a certain dB SPL level using a given speaker at a given distance.

Jason found an online calculator from Harman (the link will be posted below), but there’s one that Rob H. likes even better on the same website as the popular Online Viewing Distance Calculator.

It’s their SPL Calculator: http://myhometheater.homestead.com/splcalculator.html

and it allows you to take room gain and proximity to walls into consideration, which is important because it can make a very large difference when it comes to how many Watts are needed in a room vs. something like an outdoor venue.

Speaking of which, the Harman calculator that Jason found will work as long as you’re aware that they are assuming a loss of 6 dB SPL for every doubling of distance. That is exactly what happens when there are no walls around you. But once you’re in a room with walls, not as many decibels of output are lost when you move farther away from the speakers.

Harman’s calculator: http://www.crownaudio.com/elect-pwr-req.htm

If you want to just figure it out for yourself, you can approximate things with the following figures:

1) Start with your speaker’s sensitivity. Normally, this is stated as dB / 1 Watt / 1 meter.

But sometimes you will see it stated as dB / 2.83 Volts / 1 meter

If the sensitivity is given using 2.83 Volts instead of 1 Watt, then you will need to look at the nominal impedance specification of that speaker.

If the impedance is 8 ohms, then 2.83 Volts is the same as 1 Watt. Easy.

If the impedance is 4 ohms, then 2.83 Volts is the same as 2 Watts. This is a common way to make a 4 ohm speaker appear to be more efficient than it really is. For example, a 4 ohm speaker with a sensitivity listed as “86 dB / 2.83 Volts / 1 meter” is actually “86 dB / 2 Watt / 1 meter”. So it takes 2 Watts of power to get it to play 86 dB SPL from 1 meter away, not 1 Watt. It’s a way to fudge the numbers.

If the impedance is 6 ohms, then 2.83 Volts is the same as 1.33 Watts.

2) Now we look at our physical distance from the speaker. The sensitivity of the speaker is given at 1 meter – or about 3 feet. We’re usually farther away than that in a home theater.

The easy rule of thumb is to reduce the dB figure by 3-4 dB for every doubling of distance. So a speaker that produces 86 dB / 1 Watt / 1 meter will produce roughly 83 dB if we’re 2 meters (about 6 feet) away, still using just 1 Watt. If we double that distance again to 4 meters (about 12 feet), then we lose another 3-4 dB. So now 1 Watt is producing roughly 79 or 80 dB at this 4 meter distance.

If we are outdoors with no walls around us, every doubling of distance will reduce the output by 6 dB. But inside a typical home theater, we don’t lose as much output because the walls are reflecting quite a bit of sound energy and keeping it in the room.

3) Finally, the easy rules of thumb are that doubling the number of Watts gives you 3 dB more output. And multiplying the Watts by 10 gives you 10 dB more output.

————————————–

So putting it all together, let’s say our speaker in question has a sensitivity of 86 dB / 1 Watt / 1 meter. And let’s say we’re sitting 4 meters (about 12 feet) away. And let’s say we want to know how many Watts we’ll need in order to hit full Reference Volume. That’s 85 dB continuous, and peaks as loud as 105 dB.

So because of our 4 meter distance, we’ve lost about 3 dB when we doubled the distance from 1 meter to 2 meters, and then lost another 3-4 dB when we doubled the distance again from 2 meters to 4 meters where we are now. So our 86 dB / 1 Watt / 1 meter sensitive speaker is now producing roughly 79 dB using just 1 Watt at our seat that is about 4 meters away.

To hit 85 dB at our seat, we need to add 6 dB. Remember, doubling the Watts gives us 3 dB more output. So we double the Watts from 1 Watt to 2 Watts – that gives us 82 dB at our seat. And now we double the Watts again from 2 Watts to 4 Watts – and that gives us our target of 85 dB at our seat that is 4 meters away from the speaker.

Yup. 4 Watts. That is very often how little power it takes to hit full Reference Volume.

But now let’s hit those 105 dB peaks.

We need to get from 85 dB up to 105 dB. Remember, multiplying the Watts by 10 will give us 10 dB more output. So 40 Watts (4 Watts x 10) will get us to 95 dB.

And to hit 105 dB? We need 400 Watts!

So you can see how the power demands increase exponentially when we’re trying to produce those very loud peaks.

Still, compared to the outdoor figures, this is small potatoes. If we were losing 6 dB of output every time we doubled our distance, we’d need over 1200 Watts to hit 105 dB using this same speaker and sitting just 4 meters away. That is the figure the Harman calculator would give us. And it’s correct – but only in an outdoor setting. The SPL calculator that takes the room into consideration gives us results that are much closer to our “rule of thumb” calculation example here.

Enjoy!

AV Rant Listener Mike —

wants to connect a tactile transducer to his computer while still using his Logitech Z-5500 5.1 speaker package.

The only way to do this properly is using the 5.1 analogue audio output from his computer. Using a 3.5mm stereo “mini” plug Y-splitter, Mike can take the “center/sub” analogue output from his computer and split that 2-channel signal. He can then feed one end of that Y-splitter into his Z-5500 Control Center connection as normal. The other end of that Y-splitter can be connected to a 3.5mm – to – RCA adapter cable. That RCA cable can then feed the amplifier for his tactile transducer.

It sounds a bit complicated in text, but the ButtKicker website has more details on this connection method. The key is to use those analogue audio outputs from your computer, though.

http://www.thebuttkicker.com/gaming/G2-hookup.html

AV Rant Listener Jonathan F. —

asked about the Logitech Harmony Remotes and whether they work with Sonos.

The older Harmony models do not. But thanks to the new “Harmony Hub”, new models like the Harmony Ultimate do!

http://blog.logitech.com/2014/06/09/logitech-harmony-delivers-the-perfect-gift-for-dad-just-in-time-for-fathers-day/

Logitech actually made an announcement specifically about Sonos a couple of months ago, including a Google Hangout (hey, we use those, too!) that does a nice job of explaining some of the very cool features of the current Harmony remotes:

https://plus.google.com/u/0/events/cjmi0ii2fae4r8pgnf1pthaf8bg

Like math?

Brent Butterworth posted a handy article with “5 Simple Equations That Can Turn You Into An Audio Tech Whiz”

Definitely useful:

http://stereos.about.com/od/introductiontostereos/tp/5-Simple-Equations-That-Can-Turn-You-Into-An-Audio-Tech-Whiz.htm?nl=1

I have the Harmony Smart Control, the $130 hub and non-touchscreen remote.
http://mobile.logitech.com/en-us/product/harmony-smart-control?crid=60

Previously I used a Harmony 880. The ability to control all my devices AND my PS3 is awesome. The set-up is also easier than the older Harmony remotes. That said how you update your set-up is important: If you make changes to your set-up via the app it can update the hub over wifi but if you make changes via the web you have to connect you hub to a PC via USB which can be a hassle.

My biggest complaint is that the remote is not backlit nor do the keys glow in the dark. That said I wouldn’t get just the hub for $100, the remote is worth the extra $30. Controlling everything via the app works but can be a hassle sometimes.

If you are ok with a non-touchscreen (and non backlit) remote it is a good way to save $220.