Hi everyone,
I'm an aspiring audio engineer who's got into DIY speaker building more and more lately. I currently have Neumann KH80DSP that I'd like to replace by DIY speakers.
I'm thinking of building Froy Seas MK3, but I'm having second thoughts after reading that the crossover could be better. Price of the tweeters are another problem too. I already bought 2 Seas W15CY001 second hand.
As other DIYers, I'm always curious for tweaks and alternatives. Filtering and sealed/ported enclosures are my main concerns. So here are those questions :
I'm an aspiring audio engineer who's got into DIY speaker building more and more lately. I currently have Neumann KH80DSP that I'd like to replace by DIY speakers.
I'm thinking of building Froy Seas MK3, but I'm having second thoughts after reading that the crossover could be better. Price of the tweeters are another problem too. I already bought 2 Seas W15CY001 second hand.
As other DIYers, I'm always curious for tweaks and alternatives. Filtering and sealed/ported enclosures are my main concerns. So here are those questions :
- Can I go sealed ? With a sub, it'd help those 5" cones do the best midrange possible, right ?
- What damping should I use ? Do bitumen pads affect the overall volume ? Is sonofil enough (as seen in lautsprechershop.de kit)
- Would I get significantly better performance (especially concerning THD and transient response) with DSP filtering compared to passive crossover ? I know this question is too general to be answered. So here's the comparison : DSP combo would be FusionAmp or PWR-ICE and passive combo would be Audiophonics Ncore + Topping D10 + Madisonspeaker Froy MK3 crossover
- Do I ask myself too many questions about speakers when I'm in the shower ? 🤔
The Froy might work for a monitor, as it's pretty upfront and forward sounding. It's also very detailed and revealing. But personally I never cared for it for normal listening, because I found the sound fatiguing over time. It would probably be a good platform for an active design. The drivers are all very good.
If you've already bought a pair of SEAS W15CY001, and find the Froy TF25CF002 tweeters too expensive, what else can you do but build these?
SEAS 5INCH
Obviously it's a better way to do things in MTM, these being SEAS CA15RLY, and a series MTM might work very well with Troels' design modified:
I'd trust Troels Gravesen more than a SEAS kit, TBH.
If you want to dream about a three way, well maybe this:
PMS-EXCEL
No, bitumen panels don't reduce SPL volume. Just cabinet colouration. No, closed box is not recommended here. These are reflex drivers. DSP, I have no opinion about.
SEAS 5INCH
Obviously it's a better way to do things in MTM, these being SEAS CA15RLY, and a series MTM might work very well with Troels' design modified:
I'd trust Troels Gravesen more than a SEAS kit, TBH.
If you want to dream about a three way, well maybe this:
PMS-EXCEL
No, bitumen panels don't reduce SPL volume. Just cabinet colouration. No, closed box is not recommended here. These are reflex drivers. DSP, I have no opinion about.
I bought the W15CY001 because they're second hand and also because I saw it in a lot of builds, including Troels 2-way monitors. But I got to admit that MTM configuration of the Froy appeal me. Vertical reflections attenuation is a big plus for my non-treated ceiling.
I'd trust Troels more too. But he doesn't offer MTM configurations for those drivers. I'll go check on how to go fom a MT cabinet to a MTM one. Good idea system7 !
About bitumen pads : I was talking about space volume. I want to respect the literage of the box in case I go vented.
Why do you think those drivers aren't recommend for closed box ? Fsb/Qesb is a "ok" 85.7 Hz and DSP would allow me to correct it.
PMS-Excel do look good but I don't want wide baffle. I've never found them as true as thin baffle speakers (Lipinski L707 are ideal speakers actually)
I'd trust Troels more too. But he doesn't offer MTM configurations for those drivers. I'll go check on how to go fom a MT cabinet to a MTM one. Good idea system7 !
About bitumen pads : I was talking about space volume. I want to respect the literage of the box in case I go vented.
Why do you think those drivers aren't recommend for closed box ? Fsb/Qesb is a "ok" 85.7 Hz and DSP would allow me to correct it.
PMS-Excel do look good but I don't want wide baffle. I've never found them as true as thin baffle speakers (Lipinski L707 are ideal speakers actually)
I'm lazy. If I see Qts = 0.36 and Vas 14L, that means biggish 5" reflex to me! That and a big magnet! 
Bitumen shouldn't make a huge difference to box volume. You don't use a lot:
Harbeth Super HL5plus loudspeaker | Stereophile.com
MTM conversions are dead easy:
Vifa PL14WJ-
Double the box size, double the number of ports or make one bigger. Crossover conversion for parallel MTM is tricky. but series MTM is dead easy. Just double values of coils and resistors in the bass filter, halve the capacitors. The treble filter is unchanged. It would work well with most Troels designs, which otherwise tend to 4 ohms with his favoured midrange presence notch.
Bitumen shouldn't make a huge difference to box volume. You don't use a lot:
Harbeth Super HL5plus loudspeaker | Stereophile.com
MTM conversions are dead easy:
Vifa PL14WJ-
Double the box size, double the number of ports or make one bigger. Crossover conversion for parallel MTM is tricky. but series MTM is dead easy. Just double values of coils and resistors in the bass filter, halve the capacitors. The treble filter is unchanged. It would work well with most Troels designs, which otherwise tend to 4 ohms with his favoured midrange presence notch.
I'm lazy. If I see Qts = 0.36 and Vas 14L, that means biggish 5" reflex to me! That and a big magnet!
Not lazy at all. You're right. This Qts doesn't look ideal for closed box.
I don't think anyone is biting on this one. But I have done some basic box calculations on the SEAS E0015-08S W15CY001.
Qc 0.71 closed box comes out about 1/3 Vas: Arpeggio by Morgan Jones. Or 5L per driver. -3dB point for closed box must be about 72Hz. This is about where you might bring in a subwoofer.
Silly idea, IMO. Go for the bigger reflex. Fine in a smallish room. Worth mentioning a monitor balance tends to flat. Domestic speakers take down treble level at least 3dB. Avoids that irritating brightness with poor recordings.
My feeling is the Froy Mk. III will work well enough with Troels 5" ideas and the much cheaper but effective Seas 22 TAF/G. But a higher crossover. 3kHz is fine for a 5" speaker IMO. MT or MTM. Sounds good.
Qc 0.71 closed box comes out about 1/3 Vas: Arpeggio by Morgan Jones. Or 5L per driver. -3dB point for closed box must be about 72Hz. This is about where you might bring in a subwoofer.
Silly idea, IMO. Go for the bigger reflex. Fine in a smallish room. Worth mentioning a monitor balance tends to flat. Domestic speakers take down treble level at least 3dB. Avoids that irritating brightness with poor recordings.
My feeling is the Froy Mk. III will work well enough with Troels 5" ideas and the much cheaper but effective Seas 22 TAF/G. But a higher crossover. 3kHz is fine for a 5" speaker IMO. MT or MTM. Sounds good.
Well, take a look at Gravesen's measured Qts for the magnesium 5". Much higher than Seas published data.
I made the Troels 5" with Magnesium cones a in a smal sealed box with Q=0,8 (calculated based on Seas data and coil series resistance).
I would take these over my LS3/5a clones any time. My clones are made from Kef elements from Constructor Series, Falcon Acoustics 23aB Acoustic Butterworth filter and "Moldova" cabinets from Ebay.
I feel the Troels 5" has many of the same properties. Definitely not for "Monster Rave Party SPL" or ground shaking Bass. The 5" is very likable and less "dull" in sound and slightly more sensitive compared to the BBCs. Larger volume and reflex would definitely give deeper base, but generally speaking I prefer sealed boxes so it has not been considered by me for these speakers.
Some of this improvement should also be attributed to the much higher quality parts used in the 5" compared to the LS3/5a clone.
As far as the Troels 5" speakers go - for sealed use I think the 5" Nextel elements would "Excel" (pun intended).
On a side note - I also made these speakers because I had boxed elements waiting for a home in an PMS-Excel and needed some small quality speakers. Have not found the time for the PMS woodwork yet!
Try and read this from Heissmann - where they compare the Neumann with his DXT-Mon:
Heissmann Acoustics | DXT-MON vs. Neumann KH-120A
Heissmann Acoustics | DXT-MON vs. Neumann KH-120A
Interesting to know Troels measurements differ from Seas data.
Yes those 5" Nextel are more approriate for sealed use. But I already got those W15CY001. But I'm not married to them and if I find good price on Nextel, I'll sell CY go for it.
I should have mentionned that if I'm not into sealed boxes, it's because of the headaching process of finding the right volume and port size.
Yes those 5" Nextel are more approriate for sealed use. But I already got those W15CY001. But I'm not married to them and if I find good price on Nextel, I'll sell CY go for it.
I should have mentionned that if I'm not into sealed boxes, it's because of the headaching process of finding the right volume and port size.
The Heissmann DXT-MON diy active monitor versus the Neumann KH120A article was very interesting.
Nothing in it really! Those Hypex plate amps aren't cheap at near 400 Euros, and you need two of them, but a good investment if you like to fiddle around with stuff.
Ports aren't hard, and not very critical IMO. Smaller and shorter ones tune higher. And tuning is a matter of choice anyway. I wouldn't bother with the SEAS Nextel versions. What do you gain? But some discussion of that in the next link.
Joachim Gerhard has used SEAS 5" prestige metal drivers and the 22TAF/G extensively in the Anima. Can't see much difference between the E0015-08S W15CY001 and the H1141-08 L15RLY/P.
I wonder if he still has any Anima boxes for sale? Sonics by Joachim Gerhard cabinets and kits..
Nothing in it really! Those Hypex plate amps aren't cheap at near 400 Euros, and you need two of them, but a good investment if you like to fiddle around with stuff.
Ports aren't hard, and not very critical IMO. Smaller and shorter ones tune higher. And tuning is a matter of choice anyway. I wouldn't bother with the SEAS Nextel versions. What do you gain? But some discussion of that in the next link.
Joachim Gerhard has used SEAS 5" prestige metal drivers and the 22TAF/G extensively in the Anima. Can't see much difference between the E0015-08S W15CY001 and the H1141-08 L15RLY/P.
I wonder if he still has any Anima boxes for sale? Sonics by Joachim Gerhard cabinets and kits..
I spent a lot of time at that Heissmann site this afternoon. Lot of good stuff there, especially passive radiators, which are rare. And excellent tweeter measurements and an elegant horn adapter for the Monacor WG-300 waveguide.
I wasn't suggesting the SEAS L15RLY/P at all. Just noticing that the SEAS W15CY001 is interchangeable on the same crossover and box.
So you have more options than you might have thought. Main thing is to get this project off the ground, IMO. Worth a PM to Joachim Gerhard and Forane12 IMO. A cabinet would be a good start.
Passive crossover looks easy enough...
P.s. Somewhere in France is a bit vague to Francophiles like myself. Where do you live?
I wasn't suggesting the SEAS L15RLY/P at all. Just noticing that the SEAS W15CY001 is interchangeable on the same crossover and box.
So you have more options than you might have thought. Main thing is to get this project off the ground, IMO. Worth a PM to Joachim Gerhard and Forane12 IMO. A cabinet would be a good start.
Passive crossover looks easy enough...
P.s. Somewhere in France is a bit vague to Francophiles like myself. Where do you live?
Last edited:
There's also this one:
www.audioexcite.com >> Excellence Two – M1 DXT
It's the W12CY, but still a nice little simple design
www.audioexcite.com >> Excellence Two – M1 DXT
It's the W12CY, but still a nice little simple design
There's also this one:
www.audioexcite.com >> Excellence Two – M1 DXT
It's the W12CY, but still a nice little simple design
Goran is one of my forum favourites. Like a lot of good people, he tries to put something back rather than just take. That particular design is a bit like Eekel's Mini.
We know what that sounds like. Doesn't go loud. No bass. A bedroom speaker. OK, if you want that.
Laws of Physics, IMO. One of the best Physicists I ever met liked all the anti-matter stuff: Dirac's anti-Electron. He also took a break from it all with Claude Debussy
Why? Because Debussy broke the rules without knowing there were Rules. He just loved the Blue Notes. So did Duke Ellington. And all that Jazz.
Goran is one of my forum favourites. Like a lot of good people, he tries to put something back rather than just take. That particular design is a bit like Eekel's Mini.
We know what that sounds like. Doesn't go loud. No bass. A bedroom speaker. OK, if you want that.
Laws of Physics, IMO. One of the best Physicists I ever met liked all the anti-matter stuff: Dirac's anti-Electron. He also took a break from it all with Claude Debussy
Why? Because Debussy broke the rules without knowing there were Rules. He just loved the Blue Notes. So did Duke Ellington. And all that Jazz.
Haha
I purely saw a midrange that was close to OP's choice.I agree 100% that we need more physics to enjoy music at a higher level.
But now I just got a message that my DXT's has arrive on the post office.... so I'm off to the workshop for the day to build my next speakers on this lovely sunday
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.