Studio Moniter design

[griff]

I would like to hear all of your thoughts on producing some really high quality bookshelf speakers/studio moniters. Things like driver selection, X/O points, the stuff for the internal dampening, id like to hear it all.

SPECS
8 ohm
50Hz - 20000Khz
drivers = vifa, scanspeak, audax, seas, focal
Price limit - $500 AUD total, can be stretched if needed
MDF and possibly an aluminium sheeting exterior.

What drivers do u recommend? its a two-way obviously

Thanks for any help

 

[yugaaa]

i think there is a section of diy on the audax website.scan speak ,vifa speak areof no use asi had sent many mails to them and nevergotany replies.you could also try zalytron.com

 

[Brett]

Hi Griff,

A really high quality monitor for $A500 is a big ask, but not impossible. There is a pro speaker available called the <a href="http://www.pmcloudspeaker.com/fb1f.htm">PMC FB1</a>, which you should consider as an inspiration (don't want to say clone it 🙂 )

It uses the Vifa P17 mid-bass and D25 tweet, both available from Mass or Jaycar. I read the part numbers in a review I've since misplaced. All you need to do is design a transmission line for them, and a crossover. Neither are trivial tasks, but at least you can know affordable drivers can produce more-than-acceptable results. HiFi News and hifi+ have both reviewed them well, and they have good deep bass.

Catalogue prices for Jaycar are around $A340 for the drivers alone, and can sometimes be had on special, or $A260ish +shipping from Mass. I've heard a "version" of the Jaycar JV60(?) kit with a redesigned, ie braced and very heavy cabinet and decent crossover components, and it surprised me pleasantly with it's quality.

If you are interested in the TL FB-1 take a squizz at <a href="http://www.t-linespeakers.org/design/classic.html">Jon Risch's TL guidelines</a>. It has been a long time since I built a TL, but these make sense to me.

Something a bit left field is the Afterburner by Thorsten Loesch. Check his <a href="http://thunderstoneaudio.nav.to/">site</a>, and scroll down to the Afterburner link. The widerange drivers are about $A120 ea from cmi.com.au. Not really a "studio monitor" but they tend to cost a lot. I have just returned from the Entech trade show in Sydney, and some serious numbers were thrown around for anything at all monitor like.

Or you could hunt up some vintage Goodmans and there are lots of really excellent Pro drivers out there (bit more $$$ though unless preloved). The brands you have mentioned are only a small sample or what's available out there.

HTH
Good luck

 

[griff]

thanks for that info, i originally shyed away from TL's due to the extra work, ill give them a look though, cabinet design is not a problem for me, it is the crossover......

 

[Andrew Steele]

hey griff,

good news, this month, the Vifa D25AG and P17WJ are on special at Jaycar, the total driver prices are $256 🙂

and their JV60 Kit is also on special this month too... the speaker kit (without the boxes) are $499, they include the crossovers, ports, drivers... well everything except the box... This is good value in my eyes... it is a $70 saving over the normal cost...

 

[griff]

not bad, got any cross over ideas?

 

[Andrew Steele]

this is the one I used

if you want to use just one midbass(P17WJ) and one tweeter(D25AG) for the design, this is the crossover I used...

it is a simple design.... but I havent had any complaints...

all the risistors are 10W

 

[griff]

personally, how would you rate this system? what price range would it compare to commercially??

i dont suppose you have the box dimensions? t-line etC?

 

[timc]

Hi Griff,

I have built a pair of floor standing t-line speakers using Vifa P17WJ08 and D27??35 drivers (can't remember the part number for the tweeter of the top of my head, but its a silk dome).

I am very happy with the results. If you are interested, seeing you and I are both in Melbourne, you could even see/hear them for your self.

The crossover I used was designed using Rod Elliott article on passive crossovers (http://sound.westhost.com/lr-passive.htm), but I will eventualy move to bi-amping.

Regards,
Tim.

 

[timc]

Take2 at tring to attach the crossover schematic...
I only have a realy big picture of it and I am at work and can't find any program that will cut it down smaller.

 

[griff]

timc, what part of melb?
do you have the box design of your speaker?

 

[timc]

I am in Northcote.

I do have the plans for them somewhere... but I haven't be able to find them the last couple of times I looked.
I did design them myself, so most of the details are still in my head.

I do have some pictures of them, I can e-mail them to you.

 

[griff]

northcote is the other end of the world as far as im concerned 😉, pics would be great

 

[planet10]

really high quality bookshelf speakers

You should have a look at John K's LS3/5A inspired Focal minimonitor -- it gets very good reviews fron DIYers

dave

 

[griff]

Andrew, so far so good, do you have the box dimensions of that PMC speaker? could you please email them to me?

THanks

 

[Brett]

Dimensions

Hey Griff,
Were you asking Andrew about the dimensions of the PMC FB-1's? If so, they are,

(W x H x D) 100 x 20 x 30cm (103.5 x 28 x 34.5cm with plinth)

Cheers

 

[griff]

im really after the internal dimensions, IE, the transmission line.

thanks

 

[mikesnowdon]

PMC cloner needs help?

Hi.

Im new to this so I apologise in advance for asking silly questions.

Im currently working on the cabinet dims for the FB1. I have the external dims which can be downloaded from the pmc website. Ive managed to cut and paste the 'cut away' image of the FB1 (showing the TL and damping) onto the drawing with the external dims. Now all I need to do is find out what thickness the panels are and I'll be able to work out the rest of the dims. (A freind is a CAD expert so he will help me here) Does anyone know the cabinet wall thickness? (below is an example based on the OB1)

Next question is of course on the xo. Ive been searching and searching for a schematic of some sort but nothing yet. Ideally I'd like the latest 'i' version but the '+' would suffice. Anyone here own FB1's or know the xo setup?

This leads to the final question: Drivers.

From what I can tell the midbass is either:

Vifa M17WG-09-08 or Vifa M17WH-09-08

The tweeter I believe is:

Vifa D27TG-45-06 for the '+' version.

For the 'i' version:

[The PMC website tells us the tweeter is a 27mm SONOLEX* unit (*which I've found out is a trademark of SEAS). The unit PMC use also has a rear chamber.]

Having looked at the SEAS website I've been able to narrow it down to this:

H0881-06 27TFFC.

(I know this may not be the right theread to ask these questions but I cant figure out how to begin a new one, I guessed this might be a good place to get some ideas though)

Thanks in advance for your help and advice.

Mike

 

[mikesnowdon]

im really after the internal dimensions, IE, the transmission line.

thanks

Looks like were both on the same lines Griff. Waht are your thougts on the above?

 

[mikesnowdon]

FB1i crossovers available here: Bit pricey though. I might get one and copy it.