maybe. I like the design of the tc9.
And I like what you did with it !!!!!!!!!!
I've never heard a tranny line, but have been tossing around a small pair of 1-ways to sit on a table for a nearfield ambiophonic listener.
I too dislike the headphone "in your head" sound.
Excellent job, and thanks for building !!!!!!!!!!!!!!
Norman
And I like what you did with it !!!!!!!!!!
I've never heard a tranny line, but have been tossing around a small pair of 1-ways to sit on a table for a nearfield ambiophonic listener.
I too dislike the headphone "in your head" sound.
Excellent job, and thanks for building !!!!!!!!!!!!!!
Norman
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I think I understand (dangerous sport!):
The driver goes at the 'Thinnest' end of the spiral - where my arrow points. Thickest end is Closed, where drivers Were placed - maybe make aperiodic (sp)) 'venting'.
Damping material gets Denser towards the thick end.
Is this anywhere close forart.eu?
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Why would one want to have an expanding closed ended TL? It seems that the reflections will not be absorbed as effectively. Easy enough to model in Akabak...
if you do put a small vent there, then it becomes a coiled MLTL. There will be deeper bass but it is now reactive in acoustic impedance and a totally different animal.
if you do put a small vent there, then it becomes a coiled MLTL. There will be deeper bass but it is now reactive in acoustic impedance and a totally different animal.
I'm Usually not one for answering a question with a question, but why not?
I can find the words to express what I see in my mind, much the same way I cant explain how my 'Negative Rocker' theory surfboards work - born from 'what if' experiments to make a board go as fast as possible 'by nature of design' rather than the rider 'Making' the board go.
One of my motto's - You never know till you try.
If an expanding closed ended TL dont work, you / we have learnt some thing.
If I wasn't fighting with Eagle PCB software (the layout - three layers of 'art' - I'm trying to do would take me 1hr by hand) I'd have a go with Akabak myself.
Got home tonight and see that there is a note from the post office to pick up a parcel hanging on the door. Should be the Vifa speakers. 10 of them in this shipment. Wonder which should be built. Looking at your speaker collection in that room that had them all, I see that many of your earlier attempts are sitting on the floor or hanging on the wall but devoid of a speaker, except for the Nautaloss varients. I may start with these. Where on this site do you have the demensions for the dual driver Nautaloss monitors?
AZDoug,
Nice to have a bag of ten Vifa's. 🙂. Just because there are boxes without drivers doesn't mean they don't sound good. In my study to isolate and identify the best alignments I use the same driver and keep building and listening. The best ones get listened to longer but they all lose a driver now and then as I don't have an infinite supply. If you want to go with the FAST approach with active XO and biamp and a sub, the Nautaloss will give you the most accurate sound (what the recording engineer intended). If you don't want to employ a sub and want to have a speaker for good general listening of all kinds of music the dual driver Karlsonator would be my choice. If space on the floor is limited and you need a wall mount - the flat MLTl, Cornu or FIB would be my choice. For a single driver floor stander without a sub or with a sub, the Fh3 inspired back horn is excellent. The Nautaloss and Fh3i have the best imaging.
I will have to draw a sketch of the spiral on the Nautaloss II. It is not critical but start with a 13 in x 9 in rectangle that slants back to 12 in tall. Make the mouth tall enough to fit 2 drivers (about 9 in) and hand draw a spiral coil such that it slowly tapers to a point. Use string to measure the length of the coil path and set it at 36 inches. The excess length I convert to a round central sealed chamber. Double up the front baffle and use the high quality thick paper faced stuff on the baffle if you can. Glue the spirals starting inside coil and out. Add bracing as shown in photos - any span more than 3 in needs to be braced. Probably doesn't matter but I put curved edges on bracing to avoid hard sharp straight lines to reduce resonance peaks from reflections.
That is about it.
Good luck.
Nice to have a bag of ten Vifa's. 🙂. Just because there are boxes without drivers doesn't mean they don't sound good. In my study to isolate and identify the best alignments I use the same driver and keep building and listening. The best ones get listened to longer but they all lose a driver now and then as I don't have an infinite supply. If you want to go with the FAST approach with active XO and biamp and a sub, the Nautaloss will give you the most accurate sound (what the recording engineer intended). If you don't want to employ a sub and want to have a speaker for good general listening of all kinds of music the dual driver Karlsonator would be my choice. If space on the floor is limited and you need a wall mount - the flat MLTl, Cornu or FIB would be my choice. For a single driver floor stander without a sub or with a sub, the Fh3 inspired back horn is excellent. The Nautaloss and Fh3i have the best imaging.
I will have to draw a sketch of the spiral on the Nautaloss II. It is not critical but start with a 13 in x 9 in rectangle that slants back to 12 in tall. Make the mouth tall enough to fit 2 drivers (about 9 in) and hand draw a spiral coil such that it slowly tapers to a point. Use string to measure the length of the coil path and set it at 36 inches. The excess length I convert to a round central sealed chamber. Double up the front baffle and use the high quality thick paper faced stuff on the baffle if you can. Glue the spirals starting inside coil and out. Add bracing as shown in photos - any span more than 3 in needs to be braced. Probably doesn't matter but I put curved edges on bracing to avoid hard sharp straight lines to reduce resonance peaks from reflections.
That is about it.
Good luck.
Yes, it is current favorite. As t sounds very nice and detailed and can make so so recordings in the past cone to life because I am hearing things that I did not hear before. I like the efficiency of the Nautaloss II but it does have reduced vertical sweet spot compared to Nautaloss I. If higher SPL is not needed, the Nautaloss I has wider sweet spot vertically so works better for listening seated or standing. It is mostly in the 12kHz and above where this effect is greatest. My one reservation with any biamp dSP FAST system is the added complexity and need for room for a sub. For simplicity sometimes I miss how easy the Karlsonator mini is to setup and use.
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Nautaloss II & Sub w/ DSP Sound Clip
Here is what the Nautaloss II and Nautaloss sub + MLTL subs running through the miniDSP sounds like. This clip is full of textures and I picked it because you can hear the clean transients of the guitar, piano, and percussion. The speaker response is +/- 3dB from 42 Hz to 18 kHz and is playing at about 87 dB where the mic is. I think it is very neutral as there is no coloration, but because it is neutral, you hear a lot of nuances over the whole spectrum. Let me know what you think.
Here is what the Nautaloss II and Nautaloss sub + MLTL subs running through the miniDSP sounds like. This clip is full of textures and I picked it because you can hear the clean transients of the guitar, piano, and percussion. The speaker response is +/- 3dB from 42 Hz to 18 kHz and is playing at about 87 dB where the mic is. I think it is very neutral as there is no coloration, but because it is neutral, you hear a lot of nuances over the whole spectrum. Let me know what you think.
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Built the bottom half of a Nautaloss twin. Will put on the other side, speakers and wires tomorrow. A couple of observations of my build:
1.> this particular build was messy, and not what I want. I'll make another later.
2.> The smallest central part of the spiral is the most difficult one to glue down, the foam core tends to unbend at that point. On my next build, I'll use a needle and thread to hold the spiral tight, at the center.
1.> this particular build was messy, and not what I want. I'll make another later.
2.> The smallest central part of the spiral is the most difficult one to glue down, the foam core tends to unbend at that point. On my next build, I'll use a needle and thread to hold the spiral tight, at the center.
For the central part, I sometimes made a 4 sided tube as the initial core to start gluing the spiral. I should mention it is important to precurve the spiral by scoring it with lots of lines (1 mm apart at tight central curve) and then lay it on soft carpet and take a round object like a PVC pipe and press the pipe back and forth on the strip to precurl it. It should be so well precurved that there is little stress when gluing it. Glue 2 inches at a time when starting. Let hot melt harden before going on to next section. It does take some practice. Don't worry about it being perfect as the spiral is not visible and just serves as absorber - and not a horn throat in an open horn/TL where it would be critical to get this dimension right.
Good luck.
Good luck.
I just ran across these drivers from MCM for $6ea. The are lower Qts and lower fs which means a more powerful motor that may actually work out better for a sealed box if you plan to EQ the bass to bring it up flat.
MCM Audio Select 6 1/2" Woofer with Poly Cone and Rubber Surround 50W RMS at 8ohm | 55-2970 (552970) | MCM Audio Select
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General Specifications:
Nominal Diameter: 6.5 inch
Rated Impedance: 8 ohms
Operating Bandwidth: 60Hz ~ 8KHz
Power Handling Capacity: 50W RMS
Sensitivity (1W/M): 88 dB
Voice Coil Diameter: 1 inch
Overall frame diameter: 6.54"
Thiele-Small Parameters:
Resonance Frequency Fs: 40 Hz
DC Resistance Re: 7.2 ohm
Mechanical Q Factor Qms: 3.66
Electrical Q Factor Qes: 0.4796
Total Q Factor Qts: 0.424
Equivalent Cas air load Vas: 26.93 liters
Coil Inductance Le: .3875 mH
Efficiency Bandwidth Product EBP 83.4
Voice Coil Over Hang X-max 3.5mm
Physical Information:
Cutout: 5.60"
Mounting Depth: 2.99"
Basket: Stamped Steel
Magnet Type: 16.6 OZ
Cone Material: Polypropylene
Surround: Rubber
Dust Cap: Polypropylene
Damper: ClothSim of Nautaloss Sub with PE driver vs MCM 55-2970
The Parts Express part 299-609 Buyout 6.5 in polycone driver works quite well for the Nautaloss subwoofer in a corner-mounted configuration (12 in from walls aimed into corner) with a peak SPL of about 99 dB at 80 Hz (2.83 volts at 1 m) in a quad driver push-pull config. This explains how I was able to get 110 dB quite easily at a moderate setting on the amp. The sub needs equalization via DSP to produce a flat profile down to 42 Hz though. Given that this driver is out of stock and I am not sure when it will be in again, I am looking at a similarly priced 6.5 in driver from MCM.
Here is the MCM 55-2970 driver:
Here is the predicted SPL vs Freq for the PE 299-609 (4 ohms nominal load, sims include effect of room wall/floor reflections for corner loading):
Here is the predicted SPL vs Freq for the MCM 55-2970 (8 ohms nominal load) - the MCM has a smoother profile due to its lower Qts motor and works quite well:
Here is the PE driver at reduced 2 volt drive equivalent to same power as 2.83 volts into 8 ohms:
Now the SPL levels compare very well between the two and the MCM may sound smoother. You will just need an amp that can drive higher voltages if you use the MCM driver as it is 8 ohms.
So this looks like a very good substitute driver and I recommend trying it out - it may actually sound better.
The Parts Express part 299-609 Buyout 6.5 in polycone driver works quite well for the Nautaloss subwoofer in a corner-mounted configuration (12 in from walls aimed into corner) with a peak SPL of about 99 dB at 80 Hz (2.83 volts at 1 m) in a quad driver push-pull config. This explains how I was able to get 110 dB quite easily at a moderate setting on the amp. The sub needs equalization via DSP to produce a flat profile down to 42 Hz though. Given that this driver is out of stock and I am not sure when it will be in again, I am looking at a similarly priced 6.5 in driver from MCM.
Here is the MCM 55-2970 driver:
An externally hosted image should be here but it was not working when we last tested it.
Here is the predicted SPL vs Freq for the PE 299-609 (4 ohms nominal load, sims include effect of room wall/floor reflections for corner loading):
Here is the predicted SPL vs Freq for the MCM 55-2970 (8 ohms nominal load) - the MCM has a smoother profile due to its lower Qts motor and works quite well:
Here is the PE driver at reduced 2 volt drive equivalent to same power as 2.83 volts into 8 ohms:
Now the SPL levels compare very well between the two and the MCM may sound smoother. You will just need an amp that can drive higher voltages if you use the MCM driver as it is 8 ohms.
So this looks like a very good substitute driver and I recommend trying it out - it may actually sound better.
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I switched for the final part of build from super and hot glue to white gorilla glue. That stuff seems strong but runs even worse than hot glue.
Got the front panels hole's cut, and glued onto the front. Found at some thin wood block to glue onto the back of the front panels. This batch of dollar store foam panels are black (what they had the day I was there) I'm wondering if any kind of paint can be used to cover the completed enclosure. What paint won't melt the foam or cause the paper face to de-laminate or wrinkle?
Got the front panels hole's cut, and glued onto the front. Found at some thin wood block to glue onto the back of the front panels. This batch of dollar store foam panels are black (what they had the day I was there) I'm wondering if any kind of paint can be used to cover the completed enclosure. What paint won't melt the foam or cause the paper face to de-laminate or wrinkle?
Seal exposed foam edges with PVA glue to keep from melting with paint. Do not use water based paint as it warps the paper and will cause curling and buckling.
Thanks! Did you listen to it through headphones? The room that these speakers are in is a square which is the worst shape for an audio room and also lack wall treatments so it may sound a little reverberant and harsh. The miniDSP is a great little tool - very easy to use, cost effective and sounds great. I have a preamp, EQ, XO, and REW all in one unit for about $100. For anyone thinking about this, I highly recommend it, a no brainer and you really appreciate it when you can tune the XO on the fly in real time. Never changed a coil, cap, or resistor.