In room response?

[2litre]

Hi All,

I'm very new to the technical aspects of speakers and I have a question about "in room response" of a particular subwoofer.

I have a Boston PV-400 subwoofer. It's powered, 75w I think, and has a published low frequency of 43Hz.

Given that my room measures 9.5' x 13' and has wood floors with plaster and lath walls, how low of frequency do you think I'm actually hearing?

R/

Jim

[simon5]

Depends on many factors. Some manufacturers even add room gain in their specs.

I'd say 35 Hz, but that's just a figure out of thin air.

[2litre]

Simon5,

I'm also tracking the post 'Subwoofer with fullrange drivers'
Which sub to use with fullrange drivers ?
since it really applies to me too. I didn't want to hijack.

I'm ultimately looking for 30Hz stereo for a pair of FR125S's. I'm going to run the FR125S's in open baffle but because of room size the baffles can't be as large as I would like so I figure I'll have to cover from 90 or 100Hz and down.

I was just wondering for reference if I'm already experiencing 30Hz with my Boston or not. Not sure what it sounds or feels like besides the thumping cars at the stoplight down the street.


R/

Jim

[simon5]

Well, thumping cars are usually producing stuff higher than 30 Hz, like stupidly high SPLs at 80 Hz to get the chest punching bass.

You're probably not experiencing 30 Hz with your subwoofer. It's probably playing very quiet at that frequency.

To convince yourself, if your subwoofer can be connected to your computer, use a frequency tone generator.

[2litre]

Ah, great idea!

I can use my portable CD player mini-jack to stereo RCA cable and connect my laptop to my reciever right?

Man, I really need to get some software and test CD's. Not to stray the topic but, does anyone also have some good choices in software should one decide to really get into this hobby?

Thanks. This should be a good patch.

Jim

[simon5]

Yeah you could do that, but usually laptops got poor soundcards that can't reproduce 30 Hz loudly.

Try it anyway hehe!

To bypass this problem, I burned a CD with test tones and ran it in an old and big CD player. You know the good old kind that doesn't care if it's a CD or a CD-R and will read it anyway.

To design subwoofers, most popular free software IMHO is WinISD Pro and UniBox.