Marine grade ply that's void free is as good as Baltic Birch ply for a given thickness. Indeed, when I was actively building, all marine grade in my locale was void free, so it's what I used. Unfortunately it's no longer guaranteed void free, so I recommend making sure before spending the extra $$$.
GM
GM
planet10 said:
Even with extra bracing and/or additional layer of mdf down the outsides? ie sandwitched walls?
got a quote including MDF and cut for 2 enclosures for $190au
for less than 200 buks and I have some 8" drivers here already, I don't think I can resist trying it out
If it doesn't work, then the only loss is some glue and a little time pre-finished.compared to near on $350 for the plywood + having to cut it myself (which i admit I am not very accurate at doing re my previous 2 diy enclosures took 4 times as long to sand out the wobbly edges).
stevodude said:
IMHO... no. I am no fan of MDF. It oozes low level grunge that limits downward dynamic range.
If you use it, just be aware that you will not get the most out of the box. Plain old particle board will probably yield better sonic results and should e even cheaper.
If one were to use thinner HDF (there is one company in Oz promoting its cabs of super HDF) and significantly increase the amount of bracing you might have something. Or particle board laminated both sides with plastic laminate (formica/arborite) or even better with a layer of fiberglass.
Also keep in mind that any old 8" won't do. A mBVR is after all a bass reflex and has to be tuned for the driver.
That we have a good helping of 8" drivers with specs close enuff to work in Chang is quite unusual and one of the things that make it special... if your 8 falls in the renge it is worth trying.
dave
alandarkdale said:
Not automatically. They'll work, but you'll need to Eq them flat, either electronically or with passive components. As you mention a BSC circuit, you don't seem to be overly concerned about such things, so it's just a case of being aware of this need.
If you don't want to apply any compensation at all, then a high gain (long-path) BLH is about the only effective option for these units.
Without measured specs it's always a crapshoot, but based on published specs, a proven FE166E design's Vb can be reduced to suit, though a BLH's throat is way too large to work well enough even with a throat reducer IMO. The proof is in the doing though, so if you want to gamble the time/$$ to experiment, try to prove me wrong.
GM
GM
Geepers... I would not want to try to prove GM wrong. I have way too much respect for your writings over the years I've read this forum.
I've tried to wrap my brain around the mathcad to do a mass loaded pipe but it won't go there... I pretty much need someone else to do the design work then I can build anything.
I really liked the ML TQWP enclosures I had for the FE206 at school. I've changed jobs and had to leave them behind. So I'm on this quest.
I have way too much respect for your writings over the years I've read this forum.I've tried to wrap my brain around the mathcad to do a mass loaded pipe but it won't go there... I pretty much need someone else to do the design work then I can build anything.
I really liked the ML TQWP enclosures I had for the FE206 at school. I've changed jobs and had to leave them behind. So I'm on this quest.
This is the article that I built from. That was several years ago and different drivers from what I have on hand now.
http://www.quarter-wave.com/Project05/Project05.html
Dale
http://www.quarter-wave.com/Project05/Project05.html
Dale
OK, since you liked the others so much, build another pair except make the depth 9.5" and of course make the driver cutout smaller to suit. Also use the same BSC ckt. except you may need to temporarily use a pot to dial in the resistor to find the fixed value required and you may need to try different by-pass caps. Last, but not least, before dialing in the BSC I recommend experimenting with toeing in the speakers so that the left channel lines up with far right listening position and vice versa since the A-N driver appears to be even 'hotter' on the top end than the 206.
Please let us know how they turn out, with BSC values and any other tweaks required (if any).
GM
Please let us know how they turn out, with BSC values and any other tweaks required (if any).
GM
Half Ceinwyn
A Half Ceinwyn is a HC but with different dimensions due to the Fostex 168 es driver..provided by Scott..who else..??!!
My first go at DIYaudio...
I got some low hour drivers...first learning point is that as they get hours on them they sound better and better.
The cabinets are made of MDF (groan, groan..) but it was spare and free. Worked out fine on the table saw..even have wife appeal which is a real bonus.
I wanted to love the sound from my first creation but they just shouted at me...what had I built..
But a better location, hours on the drivers and woo hoo...acoustic guitar is real nice..Tracy Chapman..Eric Clapton Unplugged. Bass is very good..Bizzare Fruit thumps it out...the tops haven't been glued on yet and when I first got the bass really going I thought the drivers were breaking up...just the tops bouncing...hence the plant pot.
Alison Krauss vocals are beautiful but once Tina Turner starts going up the scale they still shout a bit and become fatiguing...so underlay to the rescue. Can you get phase plugs for these drivers..? Would they help..?
They will be glued down once I get the woollen underlay in...do I glue it with wood glue..?? or silicone..??..and have sorted out the brace for the driver.
The CD player is a PS1..total cost £6..as my kids broke the CD player in my Denon...which I got going after perusing another thread. My current amp is the Denon...I have a Trends TA10 from Mr Wu in HK but my wife has misplaced it in the house build / move..!! Maybe I souldn't have bought it but just gone straight for one of Mr Pass's designs..that is my next project I thnk.
I also use my laptop as a music source...high quality MP3 and FLAC sound very good. No DAC, just Windoze MP and the laptop soundcard, but I shall improve on that as I have time.
As a non HiFi audiophile who really likes his music sorry for the non-audiophile review but I hope you understand what I am trying to say and a big thank you to Mr Moose...I am in LAX later in July so your drivers will be with you shortly sir..
Many thanks.
AdrianB
A Half Ceinwyn is a HC but with different dimensions due to the Fostex 168 es driver..provided by Scott..who else..??!!
My first go at DIYaudio...
I got some low hour drivers...first learning point is that as they get hours on them they sound better and better.
The cabinets are made of MDF (groan, groan..) but it was spare and free. Worked out fine on the table saw..even have wife appeal which is a real bonus.
I wanted to love the sound from my first creation but they just shouted at me...what had I built..
But a better location, hours on the drivers and woo hoo...acoustic guitar is real nice..Tracy Chapman..Eric Clapton Unplugged. Bass is very good..Bizzare Fruit thumps it out...the tops haven't been glued on yet and when I first got the bass really going I thought the drivers were breaking up...just the tops bouncing...hence the plant pot.
Alison Krauss vocals are beautiful but once Tina Turner starts going up the scale they still shout a bit and become fatiguing...so underlay to the rescue. Can you get phase plugs for these drivers..? Would they help..?
They will be glued down once I get the woollen underlay in...do I glue it with wood glue..?? or silicone..??..and have sorted out the brace for the driver.
The CD player is a PS1..total cost £6..as my kids broke the CD player in my Denon...which I got going after perusing another thread. My current amp is the Denon...I have a Trends TA10 from Mr Wu in HK but my wife has misplaced it in the house build / move..!! Maybe I souldn't have bought it but just gone straight for one of Mr Pass's designs..that is my next project I thnk.
I also use my laptop as a music source...high quality MP3 and FLAC sound very good. No DAC, just Windoze MP and the laptop soundcard, but I shall improve on that as I have time.
As a non HiFi audiophile who really likes his music sorry for the non-audiophile review but I hope you understand what I am trying to say and a big thank you to Mr Moose...I am in LAX later in July so your drivers will be with you shortly sir..
Many thanks.
AdrianB
Attachments
Nice job Adrian,
You might want to consider making up a BSC circuit to help tune the sound to your taste. They can be a great help in reducing the shoutyness and fatigue. It's easy to do and can be done externally, if you don't like it just take it out. there is a nice explination at Martin King's site if you don't know how to go about making one.
PJN
You might want to consider making up a BSC circuit to help tune the sound to your taste. They can be a great help in reducing the shoutyness and fatigue. It's easy to do and can be done externally, if you don't like it just take it out. there is a nice explination at Martin King's site if you don't know how to go about making one.
PJN
Re: Half Ceinwyn
Although purists will be revolted by the suggestion: I would try a baffle step correction circuit.
The HCs I built benefited greatly by the addition of a BSC. For the HCs w/ FE206e drivers, I used a 1 mH inductor and 5 ohm resistor. You give up a couple dB in sensitivity, but improvement in SQ is worth it. And if you have a SS amp w/ any power in it at all, you won't notice the loss of sensitivity.
Cheers, Jim
dawnpatrol said:
Although purists will be revolted by the suggestion: I would try a baffle step correction circuit.
The HCs I built benefited greatly by the addition of a BSC. For the HCs w/ FE206e drivers, I used a 1 mH inductor and 5 ohm resistor. You give up a couple dB in sensitivity, but improvement in SQ is worth it. And if you have a SS amp w/ any power in it at all, you won't notice the loss of sensitivity.
Cheers, Jim
Given that, if I'm reading the post correctly, the tops aren't even glued on & the MDF enclosures are completely undamped, I think it might be a trifle premature to be contemplating Eq circuits.
Before anything else, they need the required damping adding & the tops gluing in place. MDF is not an especially stiff material so it too will currently be resonating right where you don't want it to -the damping & brace should take care of that. Once that's done, & assuming they're near a wall, I'd be surprised if they needed any correction. In your case Jim, IIRC, you're using the 206, which isn't ideal for this kind of load -low Q, high mass-corner, rising response over ~1.2KHz; the circuit you're using will likely be dealing more with that than step-loss itself. The 168ESig. has a higher Q, lower mass corner & a slightly flatter overall response trend so needs less adjustment for this sort of box.
Before anything else, they need the required damping adding & the tops gluing in place. MDF is not an especially stiff material so it too will currently be resonating right where you don't want it to -the damping & brace should take care of that. Once that's done, & assuming they're near a wall, I'd be surprised if they needed any correction. In your case Jim, IIRC, you're using the 206, which isn't ideal for this kind of load -low Q, high mass-corner, rising response over ~1.2KHz; the circuit you're using will likely be dealing more with that than step-loss itself. The 168ESig. has a higher Q, lower mass corner & a slightly flatter overall response trend so needs less adjustment for this sort of box.
Thanks for the comments.
Maybe I should have finished them completely first before posting. But I am pleased with what I have done so far and it is just a first step of many..I hope.
Having spent hours and hours perusing this and other diy hifi sites I am beginning to get the basics and understand their importance. Materials, burn in, the importance of a good source and amp. Time it takes to build, cost and WAF appeal.
Enjoy your weekend..where ever you are.
AdrianB
Maybe I should have finished them completely first before posting. But I am pleased with what I have done so far and it is just a first step of many..I hope.
Having spent hours and hours perusing this and other diy hifi sites I am beginning to get the basics and understand their importance. Materials, burn in, the importance of a good source and amp. Time it takes to build, cost and WAF appeal.
Enjoy your weekend..where ever you are.
AdrianB
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