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I just picked up a virtually unused REL Quake sub for $175 and thought I would give it a go with my LS50's.
The aim was to enhance the bass without interfering with the natural attributes of the LS50's.
I have found that using REW setup to measure in room humps and bumps and doing a sweep with the sub OFF then another sweep with the sub ON works well. After a bit of tweaking the sub level, moving the LS50's and sub around everything suddenly came together. A crossover of around 35hZ seems to stop any muddiness or bloat around 80hZ in my room.
I would assume the REL T-5'S would be better but the Quake has really given my LS50's some real weight without destroying the magic. I have tried a REL T-Zero. It improved bass but didn't have quite enough bottom end weight for me.
Green trace is LS50's with sub OFF and orange with sub ON.
My listening space is relatively small and it isn't practical to move furniture around and it is an awkward space with one corner on the left which is partly enclosed by the side of a cabinet. The right side of the room opens into a void with a high ceiling so I get no reflection from that side. The left side has sliding glass doors and curtains so it sounds different with the curtains closed.
I have found that my KEF LS50's respond dramatically to positioning and my REL T-Zero sub crossover frequency and level are very difficult to optimise because the LS50's are so responsive that introduction of extra bass can have a dampening effect on their sound.
I was unable to get the balance right after messing around for months trying to balance my sub and position the LS50's optimally.
I knew there were an enormous amount of REW users but I didn't think it applied to me because I couldn't make physical change to my room. WRONG!
I installed REW on my Mac and used the inbuilt mike but the readings weren't very informative. I didn't want to spend hundreds of dollars on a calibrated mike but as luck would have it, Loud Speaker Kits had Dayton Audio iMM-6 mikes for around $25 so I splurged.
After a some experimenting and variable results I got the hang of it. I took readings without the sub and was able to optimise the LS50's bass response by positioning alone. I couldn't get rid of a dip around 400 hZ but I don't notice any deficiencies.
This gave my my benchmark for the main speakers.
Optimising the sub suddenly became simple because I was able to adjust the crossover frequency to eliminate peaks then adjust the level to give a nice smooth balance between the LS50's and Sub which now pressurises my room nicely despite the unconventional shape of my room.
Now I have an amazing sounding system with gutsy, clean musical bass that has become an extension of the LS50's plus I don't have to get up all the time to fiddle with my sub any more.
Everybody NEEDS to make REW part of their system even if they can't modify their listening space.
I am using REW 5.6 on a Macbook.
The graph looks to be ok but I thought the trave should be sitting near 0dB but traces are sitting around 50db. I have configured the sound card, adjusted speaker level, mike input level and dBFS Level is sitting on -12dB and I have adjusted that but it is the same as adjusting the amp level.
I can calculate dB variations but I am wondering if there is a config that allows me to do that apart from adjusting Data Offset for each reading.
I am using a calibrated Dayton Audio iMM-6 for measurements.
Can anyone point me in the right direction please?
DIY 2-way bookshelf build from drivers without published data! (Starting from scratch measuring TS, FR, enclosure & crossover design) Help appreciatedBy Jonesy_SA
*Please Read Disclaimer at end before posting*
Iâ€™m pretty excited with what landed on my desk today; 2 x 1 inch tweeters and 2 x 5" woofers.
These are OEM from discontinued products, most likely manufactured by Tymphany/Vifa, in turn specifications such as TS and FR are unavailable; which partly explains my purchase. I have assembled speaker kits before but thought it would be fun to measure some drivers myself in order to produce a 2-way bookshelf system from scratch.
Driver data as provided by seller:
Tweeter: 25mm Soft Dome, 40 Watts â€“ 120 Watts, 8 Ohm Nominal, 25.5 Hz â€“ 20 KHz, Diameter: 94 mm, Cutout Size: 70mm
Data 50 Watts RMS 100W peak, 4 Ohm, 88 dB, 54Hz, 1" Voice Coil, Poly doped, treated paper cone. Double magnet. Dimensions: 148mm frame, Cut out size: 120mm
Having trawled Google images I'm pretty confident these came paired in a bookshelf with the following specs:
Crossover Point 1.9kHz, Nominally 6 ohms, Bass reflex rear vented, Dimensions 295mm high x 175mm wide x 240mm deep, Volume 7 litres internal.
With that said my plan is to approach from a clean slate and not replicate existing designs. I have never measured TS or FR or designed a crossover so Iâ€™m hoping you knowledgeable folk can jump in and assist.
I am unable to find a good reference explaining how to measure drivers and implement in a system, however my understanding of the process is:
(1) Measure TS parameters of woofer,
However this article raises issues with TS data and enclosure design.
(2) Design and build enclosure from TS parameters
(3) Perform frequency response testing of drivers mounted in enclosure (I think I need to obtain the impedance response of the drivers as well)
(4) Create crossover from data
(If you have a relevant link please post it â€“ links above are indicative of how I will approach that aspect)
Two software suites come to mind when looking into the above:
http://www.roomeqwizard.com/ ... REW manual: http://www.roomeqwizard.com/help/help_en-GB/html/index.html
There are others such as SpeakerWorkshop, SoundEasy etc however they are not free and do not offer lite versions. With that said, I believe most suites use the same algorithms for calculating TS, and REW is apparently quite powerful for FR analysis(?).
My aim is to update the first few posts with milestones and references to the relevant posts while the entire thread will show chronological order and discussion.
Feel free to jump in and assist :-)
#Disclaimer - I will not post the OEM brand details and would ask respondents follow suit. They are a great company that I have purchased from before and I think its fantastic end of line stock is released onto the market and not made landfill; however they may not like their brand name popping up in a DIY thread from Google searches. I would also encourage those that wish to build a speaker kit perhaps look at Loud Speaker Kit (LSK). Their bang for buck drivers are most likely a better option and their kits are well designed#
OK, so I've downloaded Room EQ Wizard and I'm looking forward to spending many hours playing with it, using it to evaluate my new lounge acoustics and getting very confused about room frequencies and nodes and all that great stuff, but...
I need a microphone to play with it properly and since I have such a broad range to choose from (from $12 to over $200, and that's just on ebay) I was just wondering, does the microphone matter much?
Or, to put it another way, which microphone should I buy to share my future analysis trials and tribulations with me.