AVS Forum banner
1 - 6 of 6 Posts

·
Registered
Joined
·
970 Posts
Discussion Starter · #1 ·
I built a QSC 2150 clone using all OEM parts except the box of course. Im not getting the bass I was expecting. Im wondering how much fill to put inside the box? Should I just line the edges and leave it hollow or pack the whole thing with foam? if so, loose or tight? Will that give me MORE bass. meaning tighter, louder, or punchier or is the OEM crossover and the type of 15" speaker they use at its limit? Thanks for your help..

below is the link to their specs.

http://qscaudio.com/products/speakers/dcs/dcs_sc2150.htm
 

·
Registered
Joined
·
508 Posts
The specs state that it's at -6db at 38Hz. You'd be better off pairing it with a subwoofer for some low/loud bass.
 

·
Registered
Joined
·
970 Posts
Discussion Starter · #3 ·
I added a 15" 1,000 watt sub. I was just wondering if the bass im hearing is accurate or If I should hear more. I know its difficult to describe. I can turn it up pretty loud but the 15" woofers are barely moving. No depth or boom in the bass. it sounds dead. I can place my hand against it and feel some vibrations but I honestly get more (punch) from my cheap bose rears. Thats why I was wondering if I need to add more acoustic foam inside the box. Maybe too much air is circulating inside. OR maybe its the design of the speaker. after all, its made for movies NOT music.
 

·
Registered
Joined
·
2,375 Posts
The frequency response specs state that they are with recommended QSC processing. Makes me wonder if they do some EQ'ing to the bass.


The woofer cabinet should be lined with something but not filled, either way it will not change bass output much if any. Dual ported high efficiency 15's should have some real in your face bass/midbass punch. Do you have any way to measure the frequency response at your LP.


Also how do you have the woofers wired? They should be in parallel.
 

·
Banned
Joined
·
15,491 Posts

Quote:
Originally Posted by rlhaudio  /t/1468913/1st-diy-speaker-help#post_23220633


I built a QSC 2150 clone using all OEM parts except the box of course. Im not getting the bass I was expecting.
Your expectations were probably unrealistic. They're listed as -6dB at 38Hz, and that's with processing. As is the case with all pro-sound/cinema speakers they're made to go loud in large spaces, not low in small spaces.
Quote:
Im wondering how much fill to put inside the box?
Vented cabs aren't filled, they're lined with a couple of inches of foam, polyester batting or type 700 fiberglass.
Quote:
OR maybe its the design of the speaker. after all, its made for movies NOT music.
It's made for theaters, not homes. But for music it should be hellaciously loud, so chances are you made a serious error in the box design or with your electronics if it's not.
 

·
Registered
Joined
·
970 Posts
Discussion Starter · #6 ·
Oh yes they are super loud, they fill my entire basement. I only lined the cabinet with foam NOT filled. I believe you are correct, pro speakers are meant to be loud not accurate. I guess I was hoping for a more realistic instrument sound ie, drum beat, guitar strings, depth and soundstage etc. I own a pair of B&W 802D as well which sound great for 2 ch. music. I wanted to try my had at DIY since its much cheaper and I will NEVER pay that much for speakers again. These cost about $600.00 each compared to $7500 ea. just ridiculous. Im using a Denon 4311ci receiver for power.


MTG90
, they are connected parallel in fact you cant connect them incorrectly. They are pre wired from the manufacturer with diff. length wires. 2 shorter wires can only reach the top woofer while the 2 longer reach the bottom. Im confident they are connected correctly, I guess I was just expecting bone rattling bass.

I do love DIY and was thinking of building the jim holtz statements next. Perhaps those will offer the accurate musical sound im looking for. (for my other room).

The SC2150 do sound great for movies, your mind can fill in any blanks, your so into the visual effects that you dont concentrate on accurate sounds.

p.s. if you want LOUD home theater speakers for a cheap price, this is it.. but they are monsters. I added a 15" dayton titan and im adding my 15" B&W 855. That should take care of the bass issue.

I wonder if QSC pairs the 2150 with a pro amp that has bass equalization? I assumed my Denon was good enough.


btw, what can I buy to measure the bass frequency response? I only have an SPL meter.


Sorry, if these questions sound redundant, im very new at this, and since im now on disabiltiy I have time to work on more hobbies.
 
1 - 6 of 6 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top