Hello all,
This is my first attempt at DIY speakers. I am intrigued by the F.A.S.T design for the Full Rangers. The Rethm speakers are something that I love and they do have Full Range drivers with an active bass module. I own a center speaker from Rethm's stable and they sound wonderful as a single driver speaker. Their Two-way speakers have got rave reviews and the most recent budget model that they launched costs a small bit of fortune for entry level enthusiast like me. The driver that they have used costs about Rs.950 per pair (less than $15 per pair) Having the tasted the flavour for single driver, I wanted to do something DIY with these drivers. And there started the temptation.
In a rush of blood, I bought a pair of HQ4814P drivers and a pair of Dainty SUB200SPP subwoofers (they were the cheapest that I could get).
Only then did I come to know that the sensitivity of FR (93db) and SW(86db) were poles apart. Worse still, the technical parameters of the SW drivers are not available online. I have tried emailing the manufacturer and distributor but no avail.
Nevertheless, I want to proceed with F.A.S.T design. I also made an assumption that it was possible to do a passive crossover to split speaker level input into LF for SW and the rest for FR (approximately @ 100 hz). I then extended the thought that I could feed these LF into a SW amplifier powered by decent transformer and pump the 200W Subwoofer.
I am accountant by profession who has a little exposure on soldering. Beyond that, I thought that it would be as simple as assembling a PC and only building the cabinet would a challenge (I am hiring a carpenter for that!!).
I do have the exit route of doing just the FR speakers alone. But, I would like to seek your opinion if my original plan is possible or not? I would like to pursue that option before settling for the easier route. I do not mind if the bass is muddied up if I do not get SW enclosure to tee.
But, I want to understand if the passive crossover for SW is possible or not. And if yes, would I be able to amplify it with SW amplifier kit like this and get the SW working
This is my first attempt at DIY speakers. I am intrigued by the F.A.S.T design for the Full Rangers. The Rethm speakers are something that I love and they do have Full Range drivers with an active bass module. I own a center speaker from Rethm's stable and they sound wonderful as a single driver speaker. Their Two-way speakers have got rave reviews and the most recent budget model that they launched costs a small bit of fortune for entry level enthusiast like me. The driver that they have used costs about Rs.950 per pair (less than $15 per pair) Having the tasted the flavour for single driver, I wanted to do something DIY with these drivers. And there started the temptation.
In a rush of blood, I bought a pair of HQ4814P drivers and a pair of Dainty SUB200SPP subwoofers (they were the cheapest that I could get).
Only then did I come to know that the sensitivity of FR (93db) and SW(86db) were poles apart. Worse still, the technical parameters of the SW drivers are not available online. I have tried emailing the manufacturer and distributor but no avail.
Nevertheless, I want to proceed with F.A.S.T design. I also made an assumption that it was possible to do a passive crossover to split speaker level input into LF for SW and the rest for FR (approximately @ 100 hz). I then extended the thought that I could feed these LF into a SW amplifier powered by decent transformer and pump the 200W Subwoofer.
I am accountant by profession who has a little exposure on soldering. Beyond that, I thought that it would be as simple as assembling a PC and only building the cabinet would a challenge (I am hiring a carpenter for that!!).
I do have the exit route of doing just the FR speakers alone. But, I would like to seek your opinion if my original plan is possible or not? I would like to pursue that option before settling for the easier route. I do not mind if the bass is muddied up if I do not get SW enclosure to tee.
But, I want to understand if the passive crossover for SW is possible or not. And if yes, would I be able to amplify it with SW amplifier kit like this and get the SW working
Just checking in to see how the project is coming along. I did a sealed HQ48414P with JBL GTO1214D (wired as 8 ohms).
For each 3dB change in sensitivity the power requirement in wattage halves or doubles.
So to get the same output from 86dB you'll have to quadruple the sub-amp's power to match the full-rangers. I just opted in for Visaton FR10 8ohms to match the sensitivity at 86dB.
Passive crossovers in my opinion are horrible. They have phase mismatches, distortion characteristics and are difficult to assemble due to availability of parts and quite a challenge to get right. I just used bi-amping and used a LR 24db crossover from Linkwitz-Riley Electronic Crossover It is phase coherent and has no peaks and dips at the crossover frequency.
But I do wish I build an amp that can power my subs at 160W to make up for the sensitivity mismatch between the full rangers running at 40W.
For each 3dB change in sensitivity the power requirement in wattage halves or doubles.
So to get the same output from 86dB you'll have to quadruple the sub-amp's power to match the full-rangers. I just opted in for Visaton FR10 8ohms to match the sensitivity at 86dB.
Passive crossovers in my opinion are horrible. They have phase mismatches, distortion characteristics and are difficult to assemble due to availability of parts and quite a challenge to get right. I just used bi-amping and used a LR 24db crossover from Linkwitz-Riley Electronic Crossover It is phase coherent and has no peaks and dips at the crossover frequency.
But I do wish I build an amp that can power my subs at 160W to make up for the sensitivity mismatch between the full rangers running at 40W.
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Sorry but it is not possible to do that, at least with that speakers, due to the big difference in sensitivity - an Lpad for the FR would dissipate a lot of power and it isn't quite engineerely clever- but in general it is good rule to go ACTIVE for those crossover frequencies as the coils& caps gets BIG and could cost more than the speakers.
That amplifier in the link would work but it needs an ACTIVE crossover ( OP-Amp based, 2nd, 3rd or 4th order low pass, Butterworth, Bessel type ).
As you might find, subwoofers amplifiers ( called plate amplifiers) always incorporate active filtering, some also for high-passing the mains ( that could be done also passively at line level )
Couldn't make my mind around the design and dropped the plan for a while. Two years of meandering around DIY portals, I want to use these drivers for surrounds in a HT setup. I am inclined towards a shallow speaker in lines with Jordan VTL design. That's just the thought but have no idea as to where start with the build process. I am looking for some calculator which would help me get an output of the VTL speaker's dimensions for the TS parameters. If nothing materializes, I would end up giving away these.
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