We compared the ND25FA and the SB26ADC head to head on Saturday. The difference was quite obvious, the SB sounds much cleaner also at normal listening volumes. Lesson learned about audio memory.
I got a 30W Marantz PM4000 2nd hand for 60€ to replace the FA880 and drive the tweeters.
I also finished the cabinet for the satori, added some damping (sheep wool) and made a first quicky crossover for the satori 4-way.
Still needs a lot of cleaning up but I'm going to listen to the satori for a bit first.
I got a 30W Marantz PM4000 2nd hand for 60€ to replace the FA880 and drive the tweeters.
I also finished the cabinet for the satori, added some damping (sheep wool) and made a first quicky crossover for the satori 4-way.
Still needs a lot of cleaning up but I'm going to listen to the satori for a bit first.
I'm assuming it's a measurement thing. It would be very unlikely I wired all drivers the wrong way. When X mentioned it in the Harsch thread I inverted all drivers in Najda and listened for a while but couldn't say it sounded all that different so I'm just keeping it like this for now. I checked the wiring then too and the driver leads with the red dot go to the red wire on the speaker and the red output of the amps. I did wire the satori the wrong way on purpose because it has a 4.8mm and 6.3mm (red) spade while 10F has 4.8mm (red) and 2.8mm and I wanted to hook it up as fast as possible and I'm almost out of 4.8mm spades.
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If you don't need more than 15w then simple $6 TDA7297 with minor cap mods sounds excellent. The so called "lunch money amp". Remove pot, swap 0.22uF inputs for 3.3uF MKT, put good 2200uF Panasonic FM or Nichicon for main cap, get rid of 0.1uF decoupling cap bear chip. That turns it into a hifi amp.
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I have these 3886 boards with opa2604 preamp built in - they sound excellent.
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I am quite surprised how well the ND25FA kept up with your system. You should try having positive rising edge pulses.
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Was it a listening test with a stereo setup? I'll agree that it isn't a huge difference but I have heard, actually more like experienced, differences. Mainly some imaging differences for whatever reason. Some recordings are inverted compared to different pressings. I think you can notice small changes between them in imaging.
Did you ever check/measure at the listening position?
I can recommend trying the free APL_TDA demo suite, both at the "design distance" and at the (final) listening position.
Be aware that REW's current frequency dependent window is giving a smoothed result. I'd also check with unsmoothed plots and gating to really know what's happening.
The IR is looking good though. Can't help but wonder about the little disturbance at ~10 ms. What does a filtered IR tab ETC plot look like?
Did you ever check/measure at the listening position?
I can recommend trying the free APL_TDA demo suite, both at the "design distance" and at the (final) listening position.
Be aware that REW's current frequency dependent window is giving a smoothed result. I'd also check with unsmoothed plots and gating to really know what's happening.
The IR is looking good though. Can't help but wonder about the little disturbance at ~10 ms. What does a filtered IR tab ETC plot look like?
Chiming in, related to this Q: Acourate FIR correction (via MiniDSP Open DRC-DI) also inverts.
Unless comparing head to head I listen in stereo. In any case inverting the drivers in Najda takes only 3 button presses to load the inverted FIR config.
Thanks for the suggestions X, I'm still really curious to hear some of these chip-amps but they need to be used in a living room so I need a box and speaker posts and RCA inputs which add significant cost. I also don't have the tools to drill holes with sub mm precision and admit to wanting things to look nice 😱.
Building Najda was my first electronics project and although I have a soldering iron and I'm not afraid to use it I don't enjoy it much. (accidentally buying a 110V power supply and having it blow up after hooking it up didn't help with my confidence... I was so focused on checking and understanding all the different properties of the PSUs I forgot about the most important one)
Pretty much all my audio gear is 2nd hand, value wise it's amazing and if I don't like it I can usually sell without loosing money. I'm a bit pressed on funds and with SMLS changing chips without notice I was a bit weary of going that route at the moment.
I do plan to build a nice compact amp for Achilles one day instead of having this tower of different amps. Dream system: modulus for tweet and mid, Ncore for base 😀.
I have been following the APL_TDA thread with interest and it's definitely on the to do list. I also got permission to put some damping panels at strategic locations from my gf so I intend to do some serious room measurements when I'm happy with the direct output of Achilles. The room is quite challenging, it's about 6mx11m with one side 5/6 meter is glass and one side 7/11 meter is glass. I haven't done any listening position measurements yet because the laptop is acting up. There is an echo on the test signal from REW, I don't think the output is broken because I can't here it when playing mp3 from the laptop. Maybe some sample rate issue?
@ Draki: I'm using rephase to build the crossover. I also looked at openDRC and intend to try it in the future but prefer to have my hands on all the buttons for now so I get a better understanding of what's going on.
Thanks for the suggestions X, I'm still really curious to hear some of these chip-amps but they need to be used in a living room so I need a box and speaker posts and RCA inputs which add significant cost. I also don't have the tools to drill holes with sub mm precision and admit to wanting things to look nice 😱.
Building Najda was my first electronics project and although I have a soldering iron and I'm not afraid to use it I don't enjoy it much. (accidentally buying a 110V power supply and having it blow up after hooking it up didn't help with my confidence... I was so focused on checking and understanding all the different properties of the PSUs I forgot about the most important one)
Pretty much all my audio gear is 2nd hand, value wise it's amazing and if I don't like it I can usually sell without loosing money. I'm a bit pressed on funds and with SMLS changing chips without notice I was a bit weary of going that route at the moment.
I do plan to build a nice compact amp for Achilles one day instead of having this tower of different amps. Dream system: modulus for tweet and mid, Ncore for base 😀.
I have been following the APL_TDA thread with interest and it's definitely on the to do list. I also got permission to put some damping panels at strategic locations from my gf so I intend to do some serious room measurements when I'm happy with the direct output of Achilles. The room is quite challenging, it's about 6mx11m with one side 5/6 meter is glass and one side 7/11 meter is glass. I haven't done any listening position measurements yet because the laptop is acting up. There is an echo on the test signal from REW, I don't think the output is broken because I can't here it when playing mp3 from the laptop. Maybe some sample rate issue?
@ Draki: I'm using rephase to build the crossover. I also looked at openDRC and intend to try it in the future but prefer to have my hands on all the buttons for now so I get a better understanding of what's going on.
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@ Draki: I'm using rephase to build the crossover. I also looked at openDRC and intend to try it in the future but prefer to have my hands on all the buttons for now so I get a better understanding of what's going on.[/QUOTE]
Of course. I happen to use openDRC because I am not using PC, so this is the only (TMK) separate hardware for the job....
Of course. I happen to use openDRC because I am not using PC, so this is the only (TMK) separate hardware for the job....
Use the ETC view: [v] and change to dB FS (not % FS) on the left top in the graph...
It will show you the reflections more clear. You can use the filters on the left bottom to view a specific frequency range.
I'm not sure what you mean, I use Najda a standalone DSP/pre-amp unit as a crossover and generate the FIR correction file using Rephase.
Something like this? I haven't used this tab before and at the moment have no idea how to interpret it.
Yes, like that, it shows the reflections compared to the peak signal.
As you measure up close it is down by a large amount, which is good.
So that dip at 10 ms in the STEP probably isn't a reflection acting up.
As you measure up close it is down by a large amount, which is good.
So that dip at 10 ms in the STEP probably isn't a reflection acting up.
The eggs have arrived and some pics of the inside of the satori enclosure and damping.
Making the heads will probably take me a long while. Lots of fitting, sanding cycles for the shape and at least 1 week for polyester coating, painting and varnish.
Making the heads will probably take me a long while. Lots of fitting, sanding cycles for the shape and at least 1 week for polyester coating, painting and varnish.
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Loudspeaker units are:
SUB: Dayton Titanic 12" MKIII
Power Handling (RMS)500 Watts
Power Handling (max)1000 Watts
Impedance 4 ohms
Sensitivity86 dB 1W/1m
LOW VOICE: Wavecor SW215WA01
Nominal impedance 4 Ohm
Sensitivity, 2.83V/1m 89 dB
Power handling, long term, IEC 268-5, no additional filtering 400W
Power handling, continuous, IEC 268-5, no additional filtering 150 W
MID VOICE: Bohlender Graebener Neo10 Planar Transducer
Imp - 8 ohm
SPL - 92 dB
PH - long term 100W
High Voice SEAS 27TDFC
Nominal Impedance 6 Ohms
Short Term Power Handling * 220 W
Long Term Power Handling * 90 W
Sensitivity (2.83V, 1m) 90 dB
I also agree with WeSaySo about the need for take unsmoothed measurements at listening position. Probably you will experience some issue in taking a good measurement for apl-tda due to the latency introduced by FIR convolution.
Something seems wrong with the Marantz (and it's not the easily fixable cut-out problem) 😡
Impulse response of tweeter with marantz, old pioneer xd-z65m all in one system and NAD. 2500Hz LR4
That is quite some ripple.
Impulse response of tweeter with marantz, old pioneer xd-z65m all in one system and NAD. 2500Hz LR4
That is quite some ripple.
Driver summing, LR2 at 100, LR4 at 325 and 2300. I aimed for 300 and 2500 in Rephase.
And impuls and step for individual drivers. The dip at 10ms seems to come from the satori and 22W having a dip there while 26W has it's huge peak.
And impuls and step for individual drivers. The dip at 10ms seems to come from the satori and 22W having a dip there while 26W has it's huge peak.
I made the bases for the tweeter heads and tried coating the egg with polyester. I checked first on a test piece whether the bit of solvent in the polyester would eat the styrofoam egg and nothing happened for the first 3 minutes. Thinking it was safe I coated the egg and this is how it looked after the polyester had set completely:
All in all a neat look but I was going for something a bit smoother.
For the next try I'll paint the egg first with water based paint and add a layer of watered down PVA glue on top of it. This should hopefully protect the styrofoam long enough from the solvents in the polyester.
I also went for +1dB to the Satori and -1dB on the 22W. It sounds a bit more balanced now and the satori is starting to come loose. I think imaging is improved but since the image is also noticeably higher I think it has more to do with the lower point of crossover from the 22W to satori in comparison to 10F then the drivers themselves.
All in all a neat look but I was going for something a bit smoother.
For the next try I'll paint the egg first with water based paint and add a layer of watered down PVA glue on top of it. This should hopefully protect the styrofoam long enough from the solvents in the polyester.
I also went for +1dB to the Satori and -1dB on the 22W. It sounds a bit more balanced now and the satori is starting to come loose. I think imaging is improved but since the image is also noticeably higher I think it has more to do with the lower point of crossover from the 22W to satori in comparison to 10F then the drivers themselves.
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The paint and the PVA glue worked perfect to protect the egg from the polyester. This one has 3 coatings, I'll wait until it fully settles for sanding the "entrance" so it fits snugly over the tweeter.
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