More Bass....

I like a nice story. Tell me about Jomon.

-- Ian

 

That's great (though may I assume you have no idea what the distortion figures are at those frequencies at the sorts of levels you listen at..?) but pretty unhelpful for people trying to compare your sub's performance to other options on the market. There are just too many variables, too many different ways the room can affect a sub's performance (not to mention different positions within a room...) The best way to usefully compare sub performance is by removing the room and all its variables from the equation.

But very few sub manufacturers are actually willing to do so as it presents their sub in a very unflattering light.

Dunc

 

Regarding building DIY speakers, IMO it's one area where one's chances of success are small and the likelihood of being able to build something that challeneges very good speakers for a fraction of the cost is almost non-existent.

I think a lot of people get tempted by the idea of buying a few drivers, a ready built crossover and then sticking it all in a box concocted using vague memories of school woodworking classes but the likely result is going to be a mess.

Michael.

 

What about kits Michael?

 

I hadn't considered kits. I suppose if they're well designed and they're reasonably easy to put together as the designer intended then they have every chance of performing pretty well.

Michael.

 

I would have thought it all depends on the cabinet making skills of the DIYer (IIRC, Ruark was a successful cabinet maker who ventured into speaker manufacture). The rest of the assembly should be relatively straight forward.

 

i've been having a gander at the ipl kits from devon. they look pretty good and seem to be liked by most reviews i've seen. the only problem for me personally would be constructing the x-over but i could probably pay someone to do it for me i guess - or buy a soddering(up) iron and bodge it myself.
cheers


julian

 

Julian

Do you have the space for an IB sub?

https://home.comcast.net/~infinitelybaffled/

Regards
Gary

 

i have a kitchen hatch which has me thinking.....
cheers


julian

 

Ju,

If you want to build one, I'll do the x/over for you

 

FYI pair of KEF subs for £500

Hex

 

thanks tone, i may just take you up on that. i need to ask the bloke a few questions about the rest of the construction.
cheers


julian.

 

"Build it and they will come"

 

Out of interest, as they were mentioned, does anyone have a view on whether any of the larger Wilmslow Audio speaker kits are any good?

Oh, and those Haniwa speakers are hilarious - seeing those has brightened up my morning no end . I can't think of any other speakers that have made me burst out laughing the first time I saw them!

 

Sub manufacturers quoting their figures in anechoic chambers is all well and good. But unfortunately such figures tell you next to nothing about how it will respond "in-room". Despite what many people will have you believe, (including Velodyne no doubt), having a flat response to 20hz in an anechoic chamber is NOT desirable. Unless you're looking for subs for outdoor concert use that is. Even the largest living room will have considerable bass augmentation and such a sub will be seriously overblown in any real listening environment. Impressive maybe, accurate it won't be no matter how low the THD figures are.

On the point of THD figures. It's more of a sales pitch than anything else as the human ear is very insensitive to distortion at low frequencies. I'd be willing to bet that the vast majority of people would be unable to hear the difference between 1% and 5% distortion at below 40hz in a blind test, (at 20hz you probably couldn't hear less than 10% THD). That is of course assuming that the harmonics aren't all odd and at 3khz or something. If all the harmonics are in the bass region, ie mostly 2nd and 3rd harmonic distortion then they will have to be a lot higher than most people think before they are audiable.

GTM

 

Interesting GTM. So are you advocating using room gain to extend a sub's output to 20hz flat in room? Most people would accept that speakers flat in room tend to sound anaemic and lacking in bass - probably due to the sensitivity of the human ear at these frequencies.

Again, if THD counts for little at low frequencies, could you give us some idea as to the reasons for the considerably different timbral qualities of low distortion subwoofers compared with the likes of Rel?

 

Most people are used to listening to speakers with a designed in rise in the bass between 50-100hz, so when they switch to a speaker with a genuinely flat bass response (as far as that is actually achievable in practice that is) they usually feel that the bass is lacking. Either way, whether or not most people accept that a flat room response sounds "anemic" or not has no bearing on whether the systems bass response is accurate or not. The two things are very often not mutually inclusive.

I never said it counts for little. I said it counts for less than people would believe. Our hearings ability to pick out distortion in the bass is significanlty worse than it is through the midrange and higher frequencies. Most people can't even hear 1-2% THD (in isolation not A to B comarison) through the midrange let alone the bass region.

On the point of timbral differences. Well, I don't believe you're really going to assert that the timbral differences between a Velodyne or REL sub are solely due to the differences in THD are you?? As you well know there are a multitude of other performance parameter differences between the two makes which are more than capable of making such differences. As there always are between any two speakers (even different models from the same manufacturer).

If you wanted to prove that assertion you would have to take a Velodyne sub and artificially create a THD which matches exactly the THD spectrum of a Typical REL sub. Then do blind A - B testing with the two THD settings and see what people can or can't percieve.

GTM

 

Just to say that our sensitivity to THD varies with frequency and also amplitude (loudness). Play it loud and you'll notice distortion less.

When I was experimenting with the 2" Bandor drive units - full-range in a relatively large test cabinet - I could dramatically cut the level of 2nd harmonic by opening and closing a transmission line attached to the cabinet via a port. The quality of the bass was noticeably better with less 2nd harmonic. However, the level of THD was quite large to start with (at 20Hz-40Hz frequencies).

I suspect that this is a question of degree.

 

Julian,

to go back to the original subject for a moment, I noticed theres a pair of B&W matrix 801s over at hififorsale for £1900

http://www.bwspeakers.com/downloadFile/speakerModel/ACF20F9.pdf

Could be what you are looking for?

Cheers, Robbo

 

Julian,

Get yourself some proper speakers



Seriously though, I heard a pair of these behemoths at the weekend and was very impressed. They definitely do bass. Ugly as hell though. From the picture you might think they're perhaps a bit bigger than a normal monitor speaker. They're actually about 3ft tall .

Can be had for about £6-800.

Michael.