Updated 11/23/2008 - HDTV and Surround Sound Recommendations!

[ArielAtom]

What does F3 mean? I thought that the number it was rated at is only right beside it or in an inert room - and that actual in-room bass response is lower.

Also, besides loudness and extention, a flat frequency response is surely a factor. Is this correct?

What is this group delay that you keep referring to?

I thought it was interesting that you recommended the Rocket Subwoofers. The only reason I can see that you wouldn't recommend the SVS subs is their lack of bass extension. But that can't be true, beecause another subwoofer at 25 hz gets your recommendation. Why don't you like SVS? Is it because it is ported?

Would a sealed sub reach the same SPl as a ported one? Would its musicality make up for its lack of bass extension?

That Rocket Subwoofer is right in the midst of my price range. It looks appealing, but reviews tell me that the SVS is the best sub for the price. Why do you recommend one over the other, since bass response does not favor your choice? It has the SOS feature, which may turn the tables.

I think I may have the wrong idea about rear-ported speakers. Does any sound come out of the ports, or is it strictly for air flow to increase bass extension? I really like some of the bookshelves (namely the x-ls, but I have my eye on the Rocket Sat ) but they are all rear-ported. I was experimenting with my desk today, and I could get the speakers a maximum of 6 inches off the wall (@ the thickness of the X-ls). Would this suffice? Most people in reviews give at least a foot of breating room, but I read that if they were going in a bookshelf, give them at least 3 cm to breathe. The guy at aperion said in an email that rear ported speakers get a mid-bass bump. Hmmm...

The X-ls is really big though, and it is not sealed either. Also, going with Scott Stone, the smaller the better. I am leaning toward Aperion 422s again lol. From a review:

Originally Posted by Eric LoBue

I am a bit less enamored with the subwoofer... Using the VMPS Sub with the satellites, however, spoke to just how good the Aperions really are. This combo is awesome. They complemented each other quite well. I could play them as loud as I liked and the Aperions just sounded better and better. Effortless, dynamic and fun, very tuneful with absolutely zero strain. They never became irritating, or lost detail. It left me wondering why I needed those gigantic Cornwalls at all, other than to hold up my lamp and the philodendron.

At 100 Hz the SPL drops about 5 decibels, starting at around 140 Hz, what should the sub's crossover be at?

I know that the SVS SBS-01 has some great reviews, but have been said to collapse and crowd the soundstage at low volumes and open up at high volumes. I mainly listen at lower volumes, so this is less than ideal. It is sealed, which is good, but its big. Do you agree that the 422s are a better fit in this situation?

If only there were more front-ported speakers. this would combine wall proximity tolerance and greater bass extension, right? Can you recommend any?

Thank you, you are really helping

[Shike]

Originally Posted by ArielAtom

What does F3 mean? I thought that the number it was rated at is only right beside it or in an inert room - and that actual in-room bass response is lower.

F3 is the response of the sub at -3dB, what many consider the last "usable" frequnecy. Some measure this in room, while others usually measure it anechoic where it's just the speakers response. In anechoic you get the true F3/tuning generally, which is important for group delay (explained below).

Also, besides loudness and extention, a flat frequency response is surely a factor. Is this correct?

Correct.

What is this group delay that you keep referring to?

Group delay is the time it takes to reproduce a specific frequency. It's most important in ported subs as that is where it's effected most. When your sub approaches its actual tuning frequency it takes longer to make certain frequencies, and can actually throw a sub off beat with the rest of the system. In HT, this isn't that big of a deal. In music though, it's important to have the sub tuned as low as possible so there's no possible chance of group delay interfering. This only pertains to ported though, as sealed is barely effected.

I thought it was interesting that you recommended the Rocket Subwoofers. The only reason I can see that you wouldn't recommend the SVS subs is their lack of bass extension. But that can't be true, beecause another subwoofer at 25 hz gets your recommendation.

It's the group delay from being ported and lacking bass extension.

Why don't you like SVS? Is it because it is ported?

Ported and not tuned low enough to really avoid group delay.

Would a sealed sub reach the same SPl as a ported one? Would its musicality make up for its lack of bass extension?

Its bass extension will be on par with the SVS, and it will be more responsive. However, the SPLs will be somewhat lower due to a lower driver size (10") and it being sealed. However, most subs of this grade put out more than many people actually need IMO. The Rocket sub is actually got a little bit more in terms of amp power though at 350W compared to the 320W of SVS, and it's a bit cheaper too.

That Rocket Subwoofer is right in the midst of my price range. It looks appealing, but reviews tell me that the SVS is the best sub for the price. Why do you recommend one over the other, since bass response does not favor your choice?

Explained above.

It has the SOS feature, which may turn the tables.

This helps "blend" the subwoofer in with the rest of your system, since we know that room accoustics can play into increasing dBs, it may increase stuff we don't want to. This helps it to make sure there isn't things that would interfere with your mindrange and balance.

I think I may have the wrong idea about rear-ported speakers. Does any sound come out of the ports, or is it strictly for air flow to increase bass extension?

Airflow to increase bass extension.

I really like some of the bookshelves (namely the x-ls, but I have my eye on the Rocket Sat ) but they are all rear-ported. I was experimenting with my desk today, and I could get the speakers a maximum of 6 inches off the wall (@ the thickness of the X-ls). Would this suffice?

I've heard most subs need about 4-5" when pushing a lot of air, so I don't think bookshelfs would need much more really.

Most people in reviews give at least a foot of breating room, but I read that if they were going in a bookshelf, give them at least 3 cm to breathe. The guy at aperion said in an email that rear ported speakers get a mid-bass bump. Hmmm...

I don't know what the guy at Aperion is suggesting, but it sounds strange if not fishy to say the least. Maybe a bump if you want distorted bass, or actually try tuning against a wall. I'm not even sure the latter is possible

decibels, starting at around 140 Hz, what should the sub's crossover be at?

Depending on where the +/- 3dB line is it's probably at 100Hz or 120Hz.

I know that the SVS SBS-01 has some great reviews, but have been said to collapse and crowd the soundstage at low volumes and open up at high volumes. I mainly listen at lower volumes, so this is less than ideal. It is sealed, which is good, but its big. Do you agree that the 422s are a better fit in this situation?

I don't know of any direct competition between the two. Sealed speakers need more power to move since they don't vent air out, but I'm not sure how much of a negative impact it would have. Unless I found a direct comparison between the two I'm not sure if I would really worry.

If only there were more front-ported speakers. this would combine wall proximity tolerance and greater bass extension, right? Can you recommend any?

Focal-JMlab
KEF
Wharfedale

I'd also recommend shopping at:
AudioAdvisor
ListenUp
Onecall
Accessories4Less

They are all pretty much official dealers where you can shop online so your warranty won't be screwed.

Also, one that thing I want to suggest. If you really like a set of rear ported, since they're bookshelf why don't you consider a set of stands? You can get a solid set of Dayton stands from PartsExpress for about $40. Why not just put them on the sides of your desk and aim them properly? Just as a thought

[Mike]

The chart in first page doesn't make any sense. I have a 19" now in my bedroom and it works to view from bed (6-9 feet). Why would I need 30"-64" HDTV? Wouldn't a 27 do just fine? Do you see less with an HDTV?

[pebblez]

Originally Posted by mikewill57

The chart in first page doesn't make any sense. I have a 19" now in my bedroom and it works to view from bed (6-9 feet). Why would I need 30"-64" HDTV? Wouldn't a 27 do just fine? Do you see less with an HDTV?

yes, tv's can still be viewed from that far, but the resolution and the HD imaging is lost if you sit that far away. The image becomes less sharp, and smaller or fainter images might be difficult or impossible to see.

[Deathwish238]

Originally Posted by mikewill57

The chart in first page doesn't make any sense. I have a 19" now in my bedroom and it works to view from bed (6-9 feet). Why would I need 30"-64" HDTV? Wouldn't a 27 do just fine? Do you see less with an HDTV?

It's not that it becomes difficult to see, you're just not seeing all the details you gain by going HD. I can almost guarantee that you wouldn't be able to tell the difference between a 19" monitor with a 854x480 resolution and 1280x720 resolution. You definitely will see no difference between a 1280x720 and 1920x1080 resolution monitor. Your eyes physically cannot see the difference.

[Shike]

Well, got a response from HSU in regards to my email.

Originally Posted by Poh S HSU Subs

Outdoor ground plane measurements. Home Theater magazine's response is not accurate - they summed the port and woofer output using nearfield measurements but did not take into account the relative areas of the cone and port.

". . . relative areas of the cone and port", sounds like they aren't doing a anechoic based test. Looks kind of . . . dissapointing

In other news, I found out my sub was tuned wrong so I'll be fixing today/tomorrow. Turns out I got the port lengths wrong after some closer examination.

This is what it was:



It had a massive group delay at about 25Hz, less than ideal. I noticed some issues when trying to blend it with the Focals which is the tell tale sign that something was wrong. It still got deep bass in games and my E-60s had overlapped some which covered it up some. Anyway . . .

The new FR should look like this:



No group delay is audible until about 19hz, with a wonderful F3 of 16Hz.

Shame I don't have room for a larger enclosure, with nine cubic feet it would be able to be tuned to 15Hz

If I get a chance after fixing it I'll run it through true RTA to show you in room results (if my test mic will keep up, of course)

[Deathwish238]

Originally Posted by ArielAtom

What does F3 mean? I thought that the number it was rated at is only right beside it or in an inert room - and that actual in-room bass response is lower.

It's about the point when the volume of the frequency will be 50% quieter than most of your others...dB is logarithmic so I know it's not exactly 50%

Originally Posted by ArielAtom

Also, besides loudness and extention, a flat frequency response is surely a factor. Is this correct?

Yup

Originally Posted by ArielAtom

What is this group delay that you keep referring to?

This is actually a new term to me...my research only tells me that it's the derivative of the phase shift function with respect to frequency...but I don't quite get how that really effects our sound when you only have 1 audio source. I see how it can effect your sound if you have multiple sources as the phase of the sound wave is changing...but with 1 driver what's there to interfere with?

Shike I suppose this is a question for you

Originally Posted by ArielAtom

I thought it was interesting that you recommended the Rocket Subwoofers. The only reason I can see that you wouldn't recommend the SVS subs is their lack of bass extension. But that can't be true, beecause another subwoofer at 25 hz gets your recommendation. Why don't you like SVS? Is it because it is ported?

Would a sealed sub reach the same SPl as a ported one? Would its musicality make up for its lack of bass extension?

When you port a sub you in essence give the sub 50% more power...this of course varies but I'm speaking generally. 50% more power however is not equivalent to 50% more volume.

Originally Posted by ArielAtom

That Rocket Subwoofer is right in the midst of my price range. It looks appealing, but reviews tell me that the SVS is the best sub for the price. Why do you recommend one over the other, since bass response does not favor your choice? It has the SOS feature, which may turn the tables.

Unless Shike can really explain this group delay business well...I still see no reason why you wouldn't go for the SVS.

I've actually inquired before about SVS subs because they're ported. Generally for sq you want to go sealed...but every single reply I received said not to worry about it. The sub sounds spectacular and extremely accurate even though it is ported. What more to say?

Originally Posted by ArielAtom

I think I may have the wrong idea about rear-ported speakers. Does any sound come out of the ports, or is it strictly for air flow to increase bass extension? I really like some of the bookshelves (namely the x-ls, but I have my eye on the Rocket Sat ) but they are all rear-ported. I was experimenting with my desk today, and I could get the speakers a maximum of 6 inches off the wall (@ the thickness of the X-ls). Would this suffice? Most people in reviews give at least a foot of breating room, but I read that if they were going in a bookshelf, give them at least 3 cm to breathe. The guy at aperion said in an email that rear ported speakers get a mid-bass bump. Hmmm...

The X-ls is really big though, and it is not sealed either. Also, going with Scott Stone, the smaller the better. I am leaning toward Aperion 422s again lol. From a review:


At 100 Hz the SPL drops about 5 decibels, starting at around 140 Hz, what should the sub's crossover be at?

The F3 is probably closer to 120Hz, so I'ld set the crossover to 120Hz...maybe 140Hz. You want the crossover to be a bit higher than the F3 as the crossover is gradual, not instant

Originally Posted by ArielAtom

I know that the SVS SBS-01 has some great reviews, but have been said to collapse and crowd the soundstage at low volumes and open up at high volumes. I mainly listen at lower volumes, so this is less than ideal. It is sealed, which is good, but its big. Do you agree that the 422s are a better fit in this situation?

I think the 422s would be a better fit for you given that you listen to them at a lower volume level

Originally Posted by ArielAtom

If only there were more front-ported speakers. this would combine wall proximity tolerance and greater bass extension, right? Can you recommend any?

I believe Dali has some front ported speakers...come to think of it most ported speakers I know of are rear ported

Originally Posted by ArielAtom

Thank you, you are really helping

I don't think the position of the port is a huge deal. Atleast I have never read much saying a port in the front is better than a port in the rear.

In general, sealed = greater accuracy, ported = more volume, lower frequency extension. So if you really want sq, go sealed...although a good ported speaker will generally give you a better value

[Deathwish238]

Originally Posted by Shike

Well obviously it has to have volume to match a system, but that's a general rule when it comes to speakers. A sub is a speaker, but not every speaker can be a sub. Understand?

That doesn't answer my question.

Originally Posted by Shike

Pretty weak, that means it will have a massive group delay at 20Hz that will be audible.

Explain your definition of group delay and where I can hear a speaker with a large amount of group delay.

Originally Posted by Shike

Do you really think they would do their testing in less than a anechoic chamber? You know what, I can solve any dispute as simple as this . . .

*shoots an email to HSU*

If not, then I'd say both HSU and SVS fail.

". . . relative areas of the cone and port", sounds like they aren't doing a anechoic based test. Looks kind of . . . dissapointing

...So who knows what their anechoic rated F3 would be and who knows how much group delay their sub has