AV Rack in chennai

[saran]

Any Idea how to build A simple DIY speaker stands, for Bookshelves with Parts available in and around chennai, It would be helpful for me as well as many who can't afford expensive speaker stands available readily in the market.


Thanks
Saran

 

[flanker.r]

Sure Saran,

This is a stand I made a couple of years back for a pair of Kef Coda 7s. It now serves as a stand for the holy basil after I got in my floor standers

Here are the details:

The base and the top are made of MDF. The stand actually a 5" dia PVC tube you can pick up at any hardware store. Since the pipe is hollow I had filled it with river sand (you can take them for free from any construction site, of course after requesting the security guy who is around). The sand helps is additional damping and isolates the speakers placed on top. If you want more ooph factor fill it with talc. You can paint it whatever colour you like. I opted for brown as they complimented the Coda well

They rival any top quality speaker stand and it is truly amazing. MDF is an acoustically dead material, PVC does not resonate (several leading speaker manufacturers use PVC for bass port) and river sand helps it further.

Coat of making a Pair less than Rs 900

MDF boards= Rs 450
PVC Pipe= Rs 120
Resin, glue, bonding material = Rs 80
River sand = Rs 15 (tipped the security guy for a tea when he started 'scratching his head')
Painting = Rs 150

All the best doing these! I am sure they will rival top brand speaker stands with regard to quality, purpose, aesthetics and not to mention cost!

 

[pradski]

flanker and venkat, thanks for everything,

In case many members would want it and you would be kind enough to do it for us. Can you us give an idea how much it will cost with shipping.

I just got my rack made by a furniture company for 4.5k.(was a friend am getting him a vanguard wall mount for that price)

I got it made from rubber wood. I did not know flanker will come late in build. (just joking)
this is how it looks
rack I got made.jpg :: Musical journey :: Fotopic.Net

Rubberwood rack .jpg :: Musical journey :: Fotopic.Net

I was thinking why can't a pentapod be done like a tripod. we have three on the front and two on the centers of the back and one long plank for all.
Thanks.

 

[flanker.r]

Good job pradski,

I see a turntable. Where is your phono amp? Clearly your AV receiver won't have one. Also with your centre speaker on the rack, its not good for your turntable (or even your cd player). I think you should mount the speaker on the wall and place the TT on top

Another thing thats evident from the photograph is that your racks have already started sagging. Do look into this

Build yourself the flexy DIY rack. You will enjoy it. Your existing rack would serve very well then as an excellent CD storage rack and with a few modifications even as an LP rack

I think you should still build the flexy. Would be glad to assist you.

 

[venkatcr]

Pradski, give m a little time. I shall enquire in the market for prices of the pieces, and check with some transport companies for ground shipping. I also have to work out the exact weight for shipping, I shall coordinate with Flanker, as I am very impressed with his rack.

Cheers

 

[pradski]

flanker,

I just got this rack two days back. I noticed that he has made it uneven. ( little angry with that).

About turntable, I wanted to keep it on the top. waiting for completion.

Centre speaker, there is no place on the wall.

This is how my wall is, any idea how to go about centres.

J10. partly set.jpg :: Musical journey :: Fotopic.Net

I am interested in the flexi, even venkat has promised to help.

Thank you venkat for your help to all of us.

 

[Pitchucold]

Hi Flaker / Venkat,

I have a question regarding my woofer placement.

I have placed my Velodyne VX-10 inside a Cupboard. I intend to add a shelf above the woofer for placing Power Supplies and UPS / Or two shelf instead to place DTH & DVD Player. Shelf shall be made of wood I have attached the pic. hope it gets loaded.

I have read somewhere, woofer sounds better placed inside a closed place. It is indeed. but i want to know if it s the right way and how could i make sure the vibrations are not harming what ever i place in the shelves above the woofer.

If this is not the right place to keep the Sub, would it be ok, if i remove the lower shelves in your design and PLace Sub there below in it in the floor.

I am intending to go for Bookshelves on Stand. I shall use your design for stand

Thanks in advance

regards,
Prasanna KV

 

[venkatcr]

Prasanna:

It may not be a good idea to place the sub inside a cupboard. Unless the cupboard is very well made to handle resonance, the cupboard will generate collateral vibrations and noise.

In addition, keeping electro-mechanical devices such as a CDP or a DVD Player on top of the sub is a bad idea. Unless you can create very rigid shelves that will absorb all vibrations and not allow any to be transferred to the devices, it will create resonances that will mar the performance of these devices.

Cheers

 

[flanker.r]

Hi Prasanna,

I really don't know where you read that a sub-woofer needs to be placed inside a cabinet. It is completely wrong. It needs to be placed away from from equipment. It needs to be placed at a location where it performs at its best. Ideally, this is the easiest way to find where to put your sub

Place the sub in your listening position and play some music with good bass content. Walk around the room while listening. At some points there will be higher volume, some points deeper bass and some points complete lack of bass. Place the sub in the place where you got deep bass extension. Sit back and enjoy the best performance your sub can give in your room. Also experiment with the 'Phase' switch and see it bass improves

 

[moserw]

Hi Flaker / Venkat,

I have a question regarding my woofer placement.

Prasanna KV

Hi Prasanna,

Corner of the room, open air, place a mat or something under it if it dances/moves too much due to the vibration. Corner of the room with two walls flanking it is usually the best place for a woofer especially if its a passive one. Active will thump out anyway since it will be powered so placement is not as much an issue for an active sub as compared to a passive sub. Generally recommended to place to the right or the left of the center and front left and right speakers against a wall i.e. corner of the room in line with the front left and right speakers and the center speaker.

 

[flanker.r]

Active or Passive? What has that got to do with speaker placement ?

Both are 'Thumping' air anyway and serve the same purpose. How does it matter where the amplifier is? For one its inside the enclosure and the other its outside. How can this influence speaker placement ?

 

[moserw]

Active or Passive? What has that got to do with speaker placement ?

Both are 'Thumping' air anyway and serve the same purpose. How does it matter where the amplifier is? For one its inside the enclosure and the other its outside. How can this influence speaker placement ?

In theory an active subwoofer will perform better than a passive subwoofer. Also, its felt (by some) that powering a subwoofer from the AVR puts load on the AVR hence a powered subwoofer is better and delivers better output.

Sound is a subjective matter... What I have said is only from personal experience! There was a time I had a local brand (at least I think so) called Victor as my 5.1 system for my PC (yeah before I was earning). The sub (passive) in this never really thumped till a friend suggested I play with its placement and his recommendation was placing it in a corner of the room where the sound would bounce off of the walls and when I tried it out I did find the subwoofer thumping a lot. Coming to the difference between active and passive and their placements, I have an entry level Onkyo 3100 with passive subwoofer and a friend got a Yamaha RX-V363 or a similar model (available at X-Cite for 26K) which was on par with my Onkyo, but the Yamaha has an active subwoofer which absolutely puts out better output compared to mine. The only way I could even come anywhere near the output of the Yamaha in terms of the subwoofer was again by playing with placement and going to the corner of the room whereas the Yamaha subwoofer gave pretty good output no matter where it was placed. I can also vouch for the same with a friend who got Onkyo HT-S590 with passive subwoofer and later on got an active subwoofer for the same setup. There was a huge difference with the active subwoofer once again and we could only improve output with the passive subwoofer yet again playing with placement, but never match the output of the active subwoofer. The point might be debatable that the amplifier inside the subwoofer or outside the subwoofer would provide the same output, but like I said sound is a subjective matter and to my ears at least the active/powered subwoofers give better bang for the buck and improved output than the subwoofers which are powered via the AVR or an outside amplifier.

This I have found to be true of even powered speakers like Audioengine A5, which despite being only 2.0 outpeform even THX certified 5.1 Logitech Z-5500. I have tested them both intensively side by side and the Audioengines absolutely will make you hear new sounds on an Audio CD and even mp3s when compared to the Logitech's which are THX certified (which may not mean much). Also, I have seen the Audioengine A5 outperform much vaunted FS and not just BS. To my ears at least powered speakers in the Audioengines and powered subwoofers do deliver better output when compared to passive/non-powered speakers and subwoofers at least in the same price range/category and when they are evenly matched in terms of output.

 

[flanker.r]

What happens then if I separate the amp section from an active sub-woofer (it is after all a plate amplifier mostly in class D), seal the cabinet in the place where the amp was (say with a df board just to cover the amp cavity) and play it. It now becomes a passive system with the amplifier being an external one. Are you saying there will be a drop in performance now because we have converted it to a passive system?

My take is that it will improve the bass as you have just increased the compliance volume of the enclosure. The volume occupied by the amp is now free for air and the driver sees more volume. Also with the amp removed, the amp can be driven to higher levels of output as it would not get as hot as it would have got had it been inside the enclosure

Active or passive should not make a difference. I am not refuting any of your observations but there are too many variables involved in methods you followed to arrive at this conclusion, one of which is use of computer speakers.

Performance of sub woofer solely depends on quality of drivers used (t/s parameters), enclosure design, crossover design, 'Q' factor arrived at. Active or passive would not make a difference. When you start designing a sub-woofer there is no single parameter which tells you if the sub-woofer you design should be actively powered or passively powered. You may only calculate how much power for a particular spl is required. How that power is supplied to speakers is immaterial

 

[flanker.r]

I think I understand what made you arrive at that conclusion. Your observations are afterall correct but there is more to this that what you have observed. The explanation of this phenomenon requires a separate thread

Please do see this. It is important that everyone sees this post. I have taken a real world example and tried to explain the reasons for people thinking active subs are better than passives. This is a must read and will benefit all HT shoppers

http://www.hifivision.com/what-shou...s-big-big-ride-real-case-study.html#post24397


Thanks

 

[moserw]

I think I understand what made you arrive at that conclusion. Your observations are afterall correct but there is more to this that what you have observed. The explanation of this phenomenon requires a separate thread

Please do see this. It is important that everyone sees this post. I have taken a real world example and tried to explain the reasons for people thinking active subs are better than passives. This is a must read and will benefit all HT shoppers

http://www.hifivision.com/what-shou...s-big-big-ride-real-case-study.html#post24397


Thanks

Point noted flanker. Interesting write up though I would not say Onkyo 3100 woofer is bad per se. Just that I have come across active subwoofers that outperform it.

 

[flanker.r]

thanks moserw

I shall reserve my comments about the Onkyo sub. Even calling an 8" a sub is degrading a sub actually but in the era of HT anything goes!

You will definitely come across passive systems that outperform the active systems you have heard

The entire point of the write up was not to degrade Onkyo but to elucidate why the passive sub you heard did not sound good so that people don't carry a biased opinion about performance of sub based on the way it is powered

 

[pksnathan]

Dear friends,
I have been following this thread right from the beginning and it is a very interesting subject.I am only a novice in audio video equipments and not an expert and this particular thread made me think of the grand cabinets audiophiles had in the 60s and 70s-Radiograms like Grundig,Garrard,Philips etc to name a few.I want to house my turntable, amp and speakers in a similar set up like a radiogram.I request our fellow members to kindly suggest which wood is better for housing the speakers .I thought of teak wood to fabricate a cabinet.Please suggest a viable option.Thanking you,
Sincerely,
pksnathan

 

[gobble]

I got it made from rubber wood

Isn't rubberwood too light? Unless you want to fix the stand to the floor with heavy bolts ... ?

TIA

 

[gobble]

Isn't rubberwood too light? Unless you want to fix the stand to the floor with heavy bolts ... ?

TIA

Oh I thought you were talking about speaker stands. You got a whole cabinet made I see.

PS I would place the turntable right on top. The bottom shelf is awkward place for it, don't you think?

Cheers

 

[pradski]

HI gobble,

I know turntable has to be on the top. since I set up I have not gone back much in to the set up. I am stuck with something else. I have to rearrange and post pictures.