Baffled Novice That needs help

[tjw1208]

Hi All I am a first time poster and new to speaker making so please be gentle.

I have had the approval from the one who should be obeyed to build some new speakers - yay to me that was only a 4 year negotiation.

As you will see from the pics I am currently using some B&W M1s because they look good to the boss - as always design over quality in her mind. I am running a Marrantz SR7005 and know I am no getting the best out of the receiver due to the speakers.

We like the look of the B&W CM series and that is a prerequisite and how I won the negotiation they need to look good. I have trialled the CM5s and like their sound too (to give an indication of my listening preference is).

On to the room itself as you can see it is open plan with a volted/pitched ceiling at 5.4m at the apex. To put things in perspective the TV is 65inch.

The cabinet under the TV is 6.5m long and 450mm deep and we were planning to put the speakers at either end and then the centre speaker under the TV but only have the 450mm clearance to the wall.

The distance from the TV to the single wood chair with the cushions is about 5.5m and the distance from the TV to the glass doors is 8m. I have included an image of the in ceiling rears which I am happy with which sit above the glass doors.

Use of the receiver 50/50 music and HT and I like quality so all our music is in FLAC lossless format.

OK on to my skill level, I am a DIY nut, I made the cabinet, I made all the chairs you see in the photos (not the leather lounge), I laid the floorboards, hung the glass bifold doors which are 70kg each and 2.4m high (yes they work) so I am confident in my ability to build cabinets/enclosures, however, I have never built any speakers.

So after all that I am absolutely baffled (for want of a better word) on what to go for. I like some of the designs people have come up with using open baffle but as I need Left Right and centre and due to the proximity to the wall I am not sure they are an option.

Given all the above and the design direction can anyone suggest some plans (doesnt have to be prepacked kit) that are available that may help me before my head explodes as I have been trawling this forum for the last 3 weeks and am just getting more and more confused. Budget would be around $1000 for the parts only (mdf and timber I have plenty of).

Thanks in advance for your help.

 

[eriksquires]

On the low end, try my LM-1C's. You can do 5 channels plus a subwoofer with them. Their relatively small size, high cut off (70 Hz) may work well for you. Plus, the price is right. Driver cost should be around $92/speaker and the cabinets are $140 off-the-shelf from Dayton. The cabinets come with covers so they are easy to hide and make disappear. Right now you can save a little money by buying the 830991 woofers from Madisound but the tweeters from Parts Express. Shipping costs may make this a moot point.


Best,


Erik

 

[eriksquires]

Also, take whatever money is left over and invest in room acoustics. Put at least 1 GIK Soffit Trap in the corner next to the doorway, and 2 panels either side of the TV. They come in a variety of colors, and you can even have custom artwork printed on them.

Best,

Erik

 

[tjw1208]

Thats great thanks for the quick reply and your site is fantastic with heaps of info. As mentioned we like the look of the B&W CM series any suggestions on different tweeters and woofers that may add colour to the design. I was also hoping to be able to make the cabinets myself as woodworking is my major hobby so do you know if the crossovers are sold separately rather than being part of the cabinet?

 

[eriksquires]

Thats great thanks for the quick reply and your site is fantastic with heaps of info. As mentioned we like the look of the B&W CM series any suggestions on different tweeters and woofers that may add colour to the design. I was also hoping to be able to make the cabinets myself as woodworking is my major hobby so do you know if the crossovers are sold separately rather than being part of the cabinet?

Hi Twj,

Thanks, glad you like the info.

The crossovers are entirely DIY, so you'll need to scrape the schematic for the parts. There's no one stop shopping here.

You must maintain a few things if you will go custom. The volume of the cabinet, the port sizes, and the center to center distances of the drivers. Change any of these and the crossover will need to be redesigned.

I would suggest you grab the cabinet specs from the Parts-Express web site and build around that.

Best,


Erik

 

[giralfino]

You must maintain a few things if you will go custom. The volume of the cabinet, the port sizes, and the center to center distances of the drivers. Change any of these and the crossover will need to be redesigned.

Add baffle size and driver placement on the baffle.

Ralf

 

[rabbitz]

In Oz

Forget about OB in that setup due to the proximity of the rear wall.

In Australia you are better with designs using Scan Speak or SB Acoustics as they are readily available. SEAS drivers have to be bought from US suppliers (A$ too low at present) and Peerless even though they are available, the quality varies (I was a reseller) but they may have improved recently.

SB Acoustics and Scan Speak Discovery are the best bang for buck.

For designs and inspiration, see Troelsgravesen's website or for great designs search for some of Jeff Bagby's speakers such as Adelphos, Kairos, Tribute, Soprano.

DIY-Loudspeakers

DIY Speaker Components | Replacement Speakers | and Speaker kits from Meniscus Audio Group They have some of Jeff Bagby designs and a few have full design PDF but Meniscus will sell the plans for others.

http://www.speakerbits.com/ For Scan Speak drivers etc
http://www.wescomponents.com/ For SB Acoustics etc (I get trade prices)
SpeakerBug For Jantzen capacitors, inductors and other speaker related stuff (great supplier)
Soundlabs Group For Mudorf M-Cap capacitors

For the fronts and centre use the same design for the lot and a vertical TM is best for your application and forget about a sideways MTM for a centre speaker. I take it you are using a subwoofer and imagine you will continue to use the same one. To DIY a sub is easy but to find a decent plate amp in Oz is hopeless as they are mostly crap. The hard part with a sub is to get one that will do both music and movies so you have to work out your priority and choose the right driver to suit. Retail subs are quite cheap these days and Eastwood Hi Fi generally has great prices with some for less than you can build one.

You rear speakers will stay I imagine.

One thing you will have to look at is the impedance of the speaker and the load on the Receiver. Most HT Receivers do not like low impedance loads such as 4 ohm but require over 6 ohm and some 8 ohm, so you are best looking at a loudspeaker design with an impedance of 7-8 ohm to be safe.

I'm sure with your great woodworking skills you will be able to take a design and cosmetically make it to suit your room and tastes.

FWIW, my pick would be Jeff Bagby's Tribute as it sounds great, low cost, low crossover parts count and can be built in a normal box shape 200mm wide. The damping method he mentions in the design can be changed a standard BR without the full stuffing.

Good luck with your project.

 

[tjw1208]

Great thanks. Yes you are correct I have a sub and am happy with the rears. You are also correct about the AUD effect. I have been looking at the great advice from eriksquires and the numbers add up when converted to AUD and shipped.

 

[eriksquires]

Hey TJW!

I just finished the 2-way version, the LM-1 and posted it online. For the size room though I'd recommend you use 3 LM-1C's though.

One thing, when you are done, the center especially, tilt them towards the listening area. I use little brass footers under the center channel. Really changes things in a good way.


Best,


Erik

 

[eriksquires]

I should have mentioned, of course, soffit traps fit in soffits. So you can put a line of them above the television for maximum effect. I think something red for instance would really add color.