Well, if you're just wanting to cover mdf, and aren't happy with the vinyl look, the next step is veneer. You can try a peel and stick type, and then stain it. Here's a link:
http://www.tapeease.com/PSA_veneer_sheets.htm
http://www.tapeease.com/PSA_veneer_sheets.htm
The advantage of ply is that it's stronger - so it can be thinner, or have less bracing (easier construction), or get better performance out of the same design and thickness. It is quite a bit more expensive. Keep in mind that lower grades are not suitable as they have voids, and I hear this can introduce problems with noises, although I can't say I've used ply for speakers so far. If you only want to use it for its finish, then I'd say consider veneer.
I just joined diyaudio.com, but I have been posting for a while over at hometheatershack.com. Late last year I completed a sub project with a Rythmik DS15.
I took a different approach to finishing the cabinet(s) since we were redesigning our living room. My wife said I could do whatever I wanted as long as it looked good.
I find my sub setup as good as I have heard. Here is a link to my posts with pictures;
WAF Limited Sub System
I took a different approach to finishing the cabinet(s) since we were redesigning our living room. My wife said I could do whatever I wanted as long as it looked good.
I find my sub setup as good as I have heard. Here is a link to my posts with pictures;
WAF Limited Sub System
plywood finish
Hi,
Veeneer can be used but I have almost always used plywood to finish speaker boxes. As a matter of fact I make boxes out of layers of midium or high density water resistant chipboard (so far I haven't used mdf often) and plywood.
To finish a box I use 3mm plywood with nice patterns. There is no problem to get plywood in Perth. Small and large sheets from 3mm to close to one inch thick. For the box front I always use chipboard, thick and then thin plywood layers.
Plywood, like wood, allows edges to be rounded using files and sand paper. I always do it manually. Until a few years ago I could use my friend's cabinet making workshop. Unfortunately he sold his furniture business but until then he used to order all the bits for me so I paid wholesale prices and could get materials not available in normal shops.
Anyway, it's important to use water resistant glue. The best I used had rubbery consistence but I do not remember its name. I remember only it was a kind of butaprene. I also used Selly's aquaresistant glue to glue the outer finishing layer of plywood.
cheers,
Hi,
Veeneer can be used but I have almost always used plywood to finish speaker boxes. As a matter of fact I make boxes out of layers of midium or high density water resistant chipboard (so far I haven't used mdf often) and plywood.
To finish a box I use 3mm plywood with nice patterns. There is no problem to get plywood in Perth. Small and large sheets from 3mm to close to one inch thick. For the box front I always use chipboard, thick and then thin plywood layers.
Plywood, like wood, allows edges to be rounded using files and sand paper. I always do it manually. Until a few years ago I could use my friend's cabinet making workshop. Unfortunately he sold his furniture business but until then he used to order all the bits for me so I paid wholesale prices and could get materials not available in normal shops.
Anyway, it's important to use water resistant glue. The best I used had rubbery consistence but I do not remember its name. I remember only it was a kind of butaprene. I also used Selly's aquaresistant glue to glue the outer finishing layer of plywood.
cheers,
I just finished a pair of subwoofer boxes waiting for my Rythmik speakers to arrive from the US (the cheap but slow boat!).
I used MDF with factory pre-formed oak veneer, using mitre corners so that you never see the MDF, and a bevelled mitered top to give it an interesting finish. I have a lot of this veneered MDF left over from building my home, and its perfect for speakers (18mm, very dense and a professional finish when varnished)
I find "liquid nails" (Australian builders flooring glue) to be much stronger than the standard wood Sellys Aquadere and it also helps to seal the box from leaks.
Regards,
Dean
I used MDF with factory pre-formed oak veneer, using mitre corners so that you never see the MDF, and a bevelled mitered top to give it an interesting finish. I have a lot of this veneered MDF left over from building my home, and its perfect for speakers (18mm, very dense and a professional finish when varnished)
I find "liquid nails" (Australian builders flooring glue) to be much stronger than the standard wood Sellys Aquadere and it also helps to seal the box from leaks.
Regards,
Dean
Front mounted ?
I think the earlier Rythmik kits had front mounted drivers. I now find in their suggested boxes in DIY section all models are floor facing.
Can we still use front facing driver ? I'm considering their compact 12" model and height is an issue in my case. I'd prefer front mount if possible. Anyone sees a problem with that ?
Cheers,
Bratislav
I think the earlier Rythmik kits had front mounted drivers. I now find in their suggested boxes in DIY section all models are floor facing.
Can we still use front facing driver ? I'm considering their compact 12" model and height is an issue in my case. I'd prefer front mount if possible. Anyone sees a problem with that ?
Cheers,
Bratislav
Bratislav, there is no reason not to mount the driver on the front. I assume you refer to the boxes that were provided by Rythmik in the past. It is a design choice to mount a driver downfiring, and if anything questions should be raised as to whether a driver is suitable for downfiring rather than front firing. There may be problems with mounting some drivers downfiring, but no sub driver should be unsuitable for front firing, except from a cosmetic point of view where some are aesthetically challenged!
paulspencer said:
Thanks Paul !
I just thought that having slot loaded (downfiring) driver might change some of the parameters of the response, especially as Rythmik themselves say that new drivers are 'redesigned'.
I guess I should just give it a try! Their drivers BTW look fine (apart from shiny/silvery looks of the compact driver
). I'd really prefer black, should check if I could somehow fit 2 cu ft box. Bratislav
rhytmik subs
Hi,
Dean, how much did you pay for shipping two subs to Australia?
Are these 12" or 15"?
Are amps coming with the drivers or you build your own amps and use only Rhytmik servo circuit?
I'm thinking about making these subs a Christmas present for myself. Has anyone had a chance to compare 12" and 15" systems? Which sounds more natural or faithful?
cheers,
Hi,
Dean, how much did you pay for shipping two subs to Australia?
Are these 12" or 15"?
Are amps coming with the drivers or you build your own amps and use only Rhytmik servo circuit?
I'm thinking about making these subs a Christmas present for myself. Has anyone had a chance to compare 12" and 15" systems? Which sounds more natural or faithful?
cheers,
Bratislav, all the drivers are silver except the standard 12" driver. I prefer the black cone, although I can only compare it to my AV12 drivers (same manufacturer).
If 2 cu ft is too small then you can do the compact kit, but it's not much smaller at 1.5 cu ft.
It's quite easy to make a box that size not take up too much space. Just make a small footprint - make it 350 x 350mm then choose the height to get the required volume.
janusz,
The driver and amp are set up as a closed loop, and it is not a simple matter of adding the servo board to any amplifier. Some in fact are not suitable. As a result, the only way to get Direct Servo is with both the driver and amp as a kit. This makes sense to me anyway as in my view, the Rythmik Plate amps are the only ones that provide all that is appropriate for a sub in terms of the crossover. No silly eq boost to defeat. And it has a rumble filter with a few options - most don't even provide one at all.
I have not heard the 15" kit, but Brian has commented that the 12" is slightly better. I'd think the difference isn't much to speak of. Apparently it is more difficult to get the same SQ
If 2 cu ft is too small then you can do the compact kit, but it's not much smaller at 1.5 cu ft.
It's quite easy to make a box that size not take up too much space. Just make a small footprint - make it 350 x 350mm then choose the height to get the required volume.
janusz,
The driver and amp are set up as a closed loop, and it is not a simple matter of adding the servo board to any amplifier. Some in fact are not suitable. As a result, the only way to get Direct Servo is with both the driver and amp as a kit. This makes sense to me anyway as in my view, the Rythmik Plate amps are the only ones that provide all that is appropriate for a sub in terms of the crossover. No silly eq boost to defeat. And it has a rumble filter with a few options - most don't even provide one at all.
I have not heard the 15" kit, but Brian has commented that the 12" is slightly better. I'd think the difference isn't much to speak of. Apparently it is more difficult to get the same SQ
rhythmik subs
Thanks Paul,
Does the amp have low and high pass outputs?
I have an active system so I was thinking about connecting my preamp's line output with subs' line inputs (I intend to have two subs) and then taking high-pass signals from the subs to my active crossover.
That is if the line high-pass output is available on subs. Otherwise I have to add one section to my active crossover so my speaker amps would get say 150Hz plus while the subs would get everything below 150Hz.
I'd appreciate any comments on the above.
cheers,
Thanks Paul,
Does the amp have low and high pass outputs?
I have an active system so I was thinking about connecting my preamp's line output with subs' line inputs (I intend to have two subs) and then taking high-pass signals from the subs to my active crossover.
That is if the line high-pass output is available on subs. Otherwise I have to add one section to my active crossover so my speaker amps would get say 150Hz plus while the subs would get everything below 150Hz.
I'd appreciate any comments on the above.
cheers,
I think that you can get all of the info that you need at www.rythmikaudio.com If not, email Brian at Rythmik, and he would be able to answer your questions.
janusz,
The shipping costs to Australia are outlined on the rythmik site, and you can negotiate for a small discount if you are shipping a couple (I had 3 imported, 2 x 12" compact for me, 1 x 15" for a friend).
I'm still waiting for mine to arrive. The slow boat is slow and I have the cabinets waiting...
Regards,
Dean
The shipping costs to Australia are outlined on the rythmik site, and you can negotiate for a small discount if you are shipping a couple (I had 3 imported, 2 x 12" compact for me, 1 x 15" for a friend).
I'm still waiting for mine to arrive. The slow boat is slow and I have the cabinets waiting...
Regards,
Dean
janusz,
Like any plate amp, the Rythmik kits have both high level and low level connections. Yes, you can send the pre amp output to the low level inputs, then run the low level outputs to your active crossover. This will apply a 2nd order highpass filter to the output at a frequency which you select. You will need to specify this. The point you choose would depend on your speakers.
I would say 150 Hz is a bit high perhaps as a crossover point for the sub. Don't forget, most subs are lucky to get up as high as 50 Hz without making a mess out of the bass. The servo works up to 100 Hz, and beyond that point if you do not cross there, you no longer have the benefits of the servo. I wouldn't cross any higher than this, although it may be possible to still get good performance.
I would expect better performance out of a decent woofer above 100 Hz. My understanding is that it works like this. When a sub woofer is designed for high power and high excursion, when we go up higher in frequency (say above 40 Hz) where excursion isn't that great, the cone is not moving much. The small excursions are swamped by thermal and mechanical memory effects. I believe this is where the servo kits are superior to other subs, and where subtle details are recovered. However, above where the servo is operating, I believe you get more accuracy out of a woofer which is optimised for high fidelity over a smaller excursion. A woofer does not require the same compromises.
An important consideration is that the acoustic and electrical slopes should ideally sum to a match on both sides of the xo point.
What are your mains? What kind of alignment/enclosure? What slopes do you have on your active xo?
Like any plate amp, the Rythmik kits have both high level and low level connections. Yes, you can send the pre amp output to the low level inputs, then run the low level outputs to your active crossover. This will apply a 2nd order highpass filter to the output at a frequency which you select. You will need to specify this. The point you choose would depend on your speakers.
I would say 150 Hz is a bit high perhaps as a crossover point for the sub. Don't forget, most subs are lucky to get up as high as 50 Hz without making a mess out of the bass. The servo works up to 100 Hz, and beyond that point if you do not cross there, you no longer have the benefits of the servo. I wouldn't cross any higher than this, although it may be possible to still get good performance.
I would expect better performance out of a decent woofer above 100 Hz. My understanding is that it works like this. When a sub woofer is designed for high power and high excursion, when we go up higher in frequency (say above 40 Hz) where excursion isn't that great, the cone is not moving much. The small excursions are swamped by thermal and mechanical memory effects. I believe this is where the servo kits are superior to other subs, and where subtle details are recovered. However, above where the servo is operating, I believe you get more accuracy out of a woofer which is optimised for high fidelity over a smaller excursion. A woofer does not require the same compromises.
An important consideration is that the acoustic and electrical slopes should ideally sum to a match on both sides of the xo point.
What are your mains? What kind of alignment/enclosure? What slopes do you have on your active xo?
rhytmik
Thanks Paul,
I have two way crossovers I built some time ago. High pass filter is 24dB/octave Bessel (Sallen&Key config) to optomize transient response. Crossover frequency is just above 600 Hz. The low pass filter is all pass filter minus high pass filter. There is no input cap nor output cap.
The preamp I'm using at the moment is a rejuvenated Yamaha C-65 (I bought is with a few caps gone, noisy pots the tracks of which I had to polish and lubricate to restore their performance etc but it is fixed now). It has all electros replaced, rebuilt PS with fast diodes, a few new transistors etc. I also plan to replace most ICs but that is not so straighforward job. These ICs were specially made for Yamaha. Fortunately, the service manual shows all their pin connections. The amps are commercial ones at the moment but will be Stichinos I'm currently building.
The speaker system is three way. The low secton has two Dynaudio 17W75xl 12 ohm drivers - one at the top and one at the bottom, mid is Audax HM130co and tweeter is Dynaudio D260. The mid and the tweeter are crossed passively at 5kHz. The filter is first order with impedance compensation.
Boxes are closed at the moment but I think I'll add a variovent to each to dampen the low resonance peak. Basically that is it. Dynaudio woofers can be cut at 100-120Hz. Although these are good speakers they have too small linear excursion to be really used below 100Hz at higher listenning levels.
So having two Rhythmic subwoofers would allow for using their 2nd order high pass filters set to about 100Hz. The final crossover frequency can be decided when I have all the speakers. I have an SPL meter so I can use it to assist me in making the decision. The only thing I do not like is that I'll have to use long connecting cables to connect the preamp with the subs and then back to the main crossover.
The alternative is to built an additional 2nd order active crossover so I would have to use only long interconnecting cables to get signal to the subs. Although I make my interconnect cables from professional microphone cables so the screen does not carry the ground path and can be connected either to a case ground on one side or groud path but still there will be 5-6 meters of cabling per channel. I have no idea what is a better solution. What do you think?
cheers,
Thanks Paul,
I have two way crossovers I built some time ago. High pass filter is 24dB/octave Bessel (Sallen&Key config) to optomize transient response. Crossover frequency is just above 600 Hz. The low pass filter is all pass filter minus high pass filter. There is no input cap nor output cap.
The preamp I'm using at the moment is a rejuvenated Yamaha C-65 (I bought is with a few caps gone, noisy pots the tracks of which I had to polish and lubricate to restore their performance etc but it is fixed now). It has all electros replaced, rebuilt PS with fast diodes, a few new transistors etc. I also plan to replace most ICs but that is not so straighforward job. These ICs were specially made for Yamaha. Fortunately, the service manual shows all their pin connections. The amps are commercial ones at the moment but will be Stichinos I'm currently building.
The speaker system is three way. The low secton has two Dynaudio 17W75xl 12 ohm drivers - one at the top and one at the bottom, mid is Audax HM130co and tweeter is Dynaudio D260. The mid and the tweeter are crossed passively at 5kHz. The filter is first order with impedance compensation.
Boxes are closed at the moment but I think I'll add a variovent to each to dampen the low resonance peak. Basically that is it. Dynaudio woofers can be cut at 100-120Hz. Although these are good speakers they have too small linear excursion to be really used below 100Hz at higher listenning levels.
So having two Rhythmic subwoofers would allow for using their 2nd order high pass filters set to about 100Hz. The final crossover frequency can be decided when I have all the speakers. I have an SPL meter so I can use it to assist me in making the decision. The only thing I do not like is that I'll have to use long connecting cables to connect the preamp with the subs and then back to the main crossover.
The alternative is to built an additional 2nd order active crossover so I would have to use only long interconnecting cables to get signal to the subs. Although I make my interconnect cables from professional microphone cables so the screen does not carry the ground path and can be connected either to a case ground on one side or groud path but still there will be 5-6 meters of cabling per channel. I have no idea what is a better solution. What do you think?
cheers,
janusz, this is what makes the most sense to me:
Keep your woofers sealed, as that will give you a predictable 2nd order acoustic slope. Simulate to find your F3 point - probably 80 - 100 Hz. Choose that point as your crossover point and request a 4th order lowpass for the plate amp and request that the highpass line outputs have their corner frequency at your chosen crossover point.
This will give you a summed 4th order crossover without adding anything extra to your active crossover.
So you use the line level outputs from the sub as your input to the active crossover. Now you will effectively have a 3 way active crossover as the plate amp will give you a highpass for the woofers. The plate amp will have a 4th order electrical slope on the lowpass filter to the sub.
If you make the mains aperiodic you give up some excursion control and get a steeper rolloff. The sealed volume should give you a Q of 0.707.
Keep your woofers sealed, as that will give you a predictable 2nd order acoustic slope. Simulate to find your F3 point - probably 80 - 100 Hz. Choose that point as your crossover point and request a 4th order lowpass for the plate amp and request that the highpass line outputs have their corner frequency at your chosen crossover point.
This will give you a summed 4th order crossover without adding anything extra to your active crossover.
So you use the line level outputs from the sub as your input to the active crossover. Now you will effectively have a 3 way active crossover as the plate amp will give you a highpass for the woofers. The plate amp will have a 4th order electrical slope on the lowpass filter to the sub.
If you make the mains aperiodic you give up some excursion control and get a steeper rolloff. The sealed volume should give you a Q of 0.707.
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