I did a lot of listening last night with well recorded jazz trios and the transient perfect really works well. Drums, piano, stand up bass all sound very articulate and the timing of attacks was super realistic. Excellent speakers for small jazz ensembles. I have "Take 5" as 176kHz FLAC and it sounds wonderful. This simple little passive Xo works. Not having the 3inch setback is less of an issue 2 meters away - the step response on axis looks fine at 1m even.
These speakers now that they are passive are great for testing out new amps. Here is my latest FX8 lateral MOSFET amp (Bimo mod) and new LC filter capacitor bank (CMC plus 4700uF and qnty 20 x 1000uF caps per rail). Design has deep deep current reserve for enormous bass authority with very low capacitor ESR.
Here is closeup of FX8 amp:
This is actually a very easy and cost effective amp to make (ca. $50 not including PSU) and about 4hrs of soldering.
Here is setup with power supply:
Newly measured frequency and phase response all looks good (this is incredibly flat frequency response for such a simple passive xo - indicative of the great natively smooth performance of these drivers):
Measured impulse and step response:
Measured HD spectrum (this is at 0.5m so equivalent SPL at 1m is about 84dB - same as listening level SPL) - any speaker with -50dB HD spectrum is just a joy to hear as it is so clean and clear:
This amp is capable of about 50w into 8ohms and a good match for this speaker. I have been listening to several albums and they sound superb: Melody Gardot "Currency of Man" and Dave Brubeck's "In Their Own Sweet Way". The pianos on Brubeck are so clear with no audible HD and being transient perfect, are very realistic. The smooth mids give Gardot's voice a great rendition that is natural and clear. Deep bass lines are captured authoritatively with the amps powerful ability to push current into the woofer. Again, transient perfect behavior makes for great drums.
Here is closeup of FX8 amp:
This is actually a very easy and cost effective amp to make (ca. $50 not including PSU) and about 4hrs of soldering.
Here is setup with power supply:
Newly measured frequency and phase response all looks good (this is incredibly flat frequency response for such a simple passive xo - indicative of the great natively smooth performance of these drivers):
Measured impulse and step response:
Measured HD spectrum (this is at 0.5m so equivalent SPL at 1m is about 84dB - same as listening level SPL) - any speaker with -50dB HD spectrum is just a joy to hear as it is so clean and clear:
This amp is capable of about 50w into 8ohms and a good match for this speaker. I have been listening to several albums and they sound superb: Melody Gardot "Currency of Man" and Dave Brubeck's "In Their Own Sweet Way". The pianos on Brubeck are so clear with no audible HD and being transient perfect, are very realistic. The smooth mids give Gardot's voice a great rendition that is natural and clear. Deep bass lines are captured authoritatively with the amps powerful ability to push current into the woofer. Again, transient perfect behavior makes for great drums.
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Hi X,
Is it finally with the alum SB Acoustic ? Do you prefer it more than the SS 10F/8 ?
And whatever the driver, do you prefer more with the passive equivalent that direct active coupling (with maybe just a big cap for DC protection if you use it) ?
Is it finally with the alum SB Acoustic ? Do you prefer it more than the SS 10F/8 ?
And whatever the driver, do you prefer more with the passive equivalent that direct active coupling (with maybe just a big cap for DC protection if you use it) ?
No the above is 10F/8424. I don't think SB65WBAC25-4 would be this smooth although might be pretty level matched without needing the padding resistors.
Recently I have been enjoying passive crossovers more just from standpoint they let me test out new amps that I build easier. In some ways they sound better and that is evident from last set of sound clips for the FF85WK listening test. Of course, the design is everything and here, the XO designed for the FF85WK and RS225-8 happen to be interchangeable. 🙂
Lucky coincidence, but 10F can handle 60w rms vs FF85WK's 5w's so it's easier to not damage it if amp goes awry.
Recently I have been enjoying passive crossovers more just from standpoint they let me test out new amps that I build easier. In some ways they sound better and that is evident from last set of sound clips for the FF85WK listening test. Of course, the design is everything and here, the XO designed for the FF85WK and RS225-8 happen to be interchangeable. 🙂
Lucky coincidence, but 10F can handle 60w rms vs FF85WK's 5w's so it's easier to not damage it if amp goes awry.
Ah you stayed with it, good to know for measurements 🙂 I stil hesitate in my snail karma how to do with mine : the horn if I get the patience or the LX Mini pluto style if I have less courage.... totally different efficienty world !😱
X,
How about the Visaton B80? Similar sensitivity to the Fostex FF85WK, flat response akin to 10F/8424?
IIRC you had unit.
On power handling, this is what I got:
- Madisound lists the 10F/8414 8 ohms driver power handling at 15W for 100h RMS noise test (IEC 17.1) , 30W long term max power
- Madisound website lists Fostex FF85WK at 5W Rated input
- Visaton website shows B80 Rated power 30W, Max power 50 watt
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My mistake I rememebered 60w for some reason (when high passed the actual levels are much higher for short term). The B80 does indeed handle more power and I have a set but saving them for my next project: a passive xo transient perfect 3 way with the B80 as the "hole filler" driver between an RS180P-8 and RS28F-4.
I think Weltersys tried some extreme power tests on the cousin TC9FD and got close to something insane like 400w until it let out the magic smoke.
I think Weltersys tried some extreme power tests on the cousin TC9FD and got close to something insane like 400w until it let out the magic smoke.
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Not yet as the VHex+ is off getting installed in a proper case (the $8 2U case being laid out right now) at present - but will test shortly.
The "Un-Case" a users' amp case with all connections in front panel for easy access - uses an $8 2U rack mount front panel and self-heatsinks as side walls, plywood board base, open top ventilation, simple to make.
The "Un-Case" a users' amp case with all connections in front panel for easy access - uses an $8 2U rack mount front panel and self-heatsinks as side walls, plywood board base, open top ventilation, simple to make.
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I am building a new CRC filter to go between the SMPS and amp. Using 4700uF 5R 4700uF arrangement on each rail. With 330pF 2kV to 4.7R RF snubber on input, 100nF 100v C0G bypass caps on outputs. With this connected to Abletec and Vhex+ I am measuring 1mV ripple at amp input and 0.1mV ripple on amp output with audio inputs grounded. Very quiet.
Will make two of these CRC filters for a quasi dual monoblock (as SMPS is shared).
The Abletec appears to have no issue with turn on transient to charge up qnty 4 x 4700uF caps in the filters. The CRC should help de-couple the amp from the SMPS to reduce PSU rail "pumping" under heavy loads and give more isolation between two amp channels for better stereo imaging and sound stage.
Will make two of these CRC filters for a quasi dual monoblock (as SMPS is shared).
The Abletec appears to have no issue with turn on transient to charge up qnty 4 x 4700uF caps in the filters. The CRC should help de-couple the amp from the SMPS to reduce PSU rail "pumping" under heavy loads and give more isolation between two amp channels for better stereo imaging and sound stage.
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The "Un-Case" amp enclosure works. I am listening to the Vhex+ amps in their new home. The soundstage is very wide with the dual CRC PSU's even though fed by a single SMPS. I still need to cut the plywood base plate out and mount the PSU's onto the plywood.
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Measurements with VHEX+ amp
This amp and speaker combo work well together. The dynamics are outstanding - at averaging listening levels (which happen to be around 2.83v or 1 watt) the harmonic distortion is very low. Even stressed to 10.43v (13.6w) which is very loud, the distortion is quite acceptable. The impulse and step are near ideal as is the flat phase response. Overall, a nicely balanced and superb transient perfect setup.
Harmonic Distortion at 2.83v (0.5m):
Harmonic Distortion at 10.43v (the 10F is superb here - very clean):
Impulse Step Response:
Measured Phase:
This amp and speaker combo work well together. The dynamics are outstanding - at averaging listening levels (which happen to be around 2.83v or 1 watt) the harmonic distortion is very low. Even stressed to 10.43v (13.6w) which is very loud, the distortion is quite acceptable. The impulse and step are near ideal as is the flat phase response. Overall, a nicely balanced and superb transient perfect setup.
Harmonic Distortion at 2.83v (0.5m):
Harmonic Distortion at 10.43v (the 10F is superb here - very clean):
Impulse Step Response:
Measured Phase:
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FH9 MOSFET amp
Ok next amp up is one of my own design. The FH9 based on the Apex FX8. Mine uses low cost vertical hex FETs. I source from Aliexpress for $6 for 5 pairs of IRFP240/9240. They are not fakes and look and work very well. Anyhow this amp has some deep deep bass. Great mids and clear highs. No sibillance. No harshness.
Here is is with 35v rail linear supply and big fat cap bank. I am using a tiny undersized heatsink hence the fans. The fans are silent by the way. Just use a 100ohm 2w resistor between 12v supply and it slows down to inaudible but still provides cooling. Currently running 80mA bias. Output DC offset is 2mV via well matched input transistors.
Measurement with 2.83v drive into 10F/RS225:
Ok next amp up is one of my own design. The FH9 based on the Apex FX8. Mine uses low cost vertical hex FETs. I source from Aliexpress for $6 for 5 pairs of IRFP240/9240. They are not fakes and look and work very well. Anyhow this amp has some deep deep bass. Great mids and clear highs. No sibillance. No harshness.
Here is is with 35v rail linear supply and big fat cap bank. I am using a tiny undersized heatsink hence the fans. The fans are silent by the way. Just use a 100ohm 2w resistor between 12v supply and it slows down to inaudible but still provides cooling. Currently running 80mA bias. Output DC offset is 2mV via well matched input transistors.
Measurement with 2.83v drive into 10F/RS225:
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Hello xrk971,
I had couple of queries. Can I use the following woofer in FAST? I had bought this woofer some time back which is sitting idle and wanted to check with you if this can work in a FAST?
https://www.madisoundspeakerstore.c...stige-er18rnx-h1456-7-reed-paper-cone-woofer/
I have the OEM black TC9FD which I procured locally which I plan to use for the full ranger.
http://www.diyaudio.com/forums/full-range/282412-tpy03w06o0111-k-oem-black-tg9fd.html
Second query even though slightly off-topic, can you tell me what settings you use in REW to measure the frequency response? I am not sure about what window to choose and gating time I need to set. Any pointer to other threads is also fine.
TIA
I had couple of queries. Can I use the following woofer in FAST? I had bought this woofer some time back which is sitting idle and wanted to check with you if this can work in a FAST?
https://www.madisoundspeakerstore.c...stige-er18rnx-h1456-7-reed-paper-cone-woofer/
I have the OEM black TC9FD which I procured locally which I plan to use for the full ranger.
http://www.diyaudio.com/forums/full-range/282412-tpy03w06o0111-k-oem-black-tg9fd.html
Second query even though slightly off-topic, can you tell me what settings you use in REW to measure the frequency response? I am not sure about what window to choose and gating time I need to set. Any pointer to other threads is also fine.
TIA
I don't see why not. It has a nice lowish FS for a driver that size and I think they make pretty good bass in reasonable enclosures. Are you planning a monitor size speaker or floorstander? I can help you model an enclosure if you don't know how to do this?
In rew, after you make your measurement, click on the impulse tab and zoom in until you can see your measurement clearly. Your graph should have a spike and then some hash and then the line goes flat. You are looking for the point at which the flat line has another breakup, this is your first reflection. It's usually between maybe 3-7ms in a typical room. You place you window just before this. Use the gate tab to set the window.
That woofer looks very nice. Quite similar in specs to the SB29NSRX44-8 which I really like. Should work well - run some models in a sealed box and adjust for Q of about 0.6. The TYP Kevlar driver should be excellent as well. All looks good to me.
For REW use the Frequency Dependent Gate (FDW) option in IR tab. Click check box and set for 1/6th octave FDW. Put mic about 0.5m away on tweeter axis. The FDW helps to gate out reflections after first arrival so you can see what you can actually have impact with in adjusting the EQ or XO.
Good luck!
Latest amp I just tried on this speaker is the FH9 HV. 53v supply rails and 120w max (tested at 8R dummy load for 15min).
Sounds fantastic with dynamic reserve that is deep. Very smooth clear low distortion and non fatiguing. Just change BD139/140 driver transistors with KSC3503/KSA1381.
Also just built a nice CS4398 USB DAC kit ($23). Here it is with the FX8 Bimo amp. This DAC has SPDIF coax input too when not using USB for 192khz bitrate.
All these things are letting me get a little bit closer to better sound quality.
Sounds fantastic with dynamic reserve that is deep. Very smooth clear low distortion and non fatiguing. Just change BD139/140 driver transistors with KSC3503/KSA1381.
Also just built a nice CS4398 USB DAC kit ($23). Here it is with the FX8 Bimo amp. This DAC has SPDIF coax input too when not using USB for 192khz bitrate.
All these things are letting me get a little bit closer to better sound quality.
satx, thanks for pointers on REW. I plan to build monitor speakers but have no idea about designing the box.
xrk, thanks for pointers on REW. I will try these settings. Regarding the box design, can you tell me which software to use so that I can give it a shot? I am assuming there is a common software all you experts are using for this purpose. May be you all can guide me on how to do it. Sorry I am beginner at this and have not done it earlier.
Thanks
No problem. I personally like unibox for it's simplicity and accuracy. Here's a description and tutorial and I think you can download it from there too. UniBox - Unified Box Model for Loudspeaker Design - Kristian Ougaard
There is also Winisd of course, bassbox and many others, but I find Unibox the easiest to get started with. Winisd is good for comparing multiple graphs/drivers though. You also might look into Jeff Bagby's Woofer modeling program as it's easier to see all the effects of your design on one tab/screen.
If you are using a passive filter you should include it's response when you model. It'll change the way your woofer models.
I quickly come up with about 15L tuned to 45Hz for your Seas driver (no crossover effects were modeled however) This gives good power handling and OK bass extension. Xmax + 10% is reached at 60W with output of 106db before baffle losses.
Unlike X, I probably wouldn't use this driver sealed unless you plan to use them with a subwoofer or two. Your F3 will only be around 85Hz in an 8L sealed box with decent power handling.
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