chr70 mini karlsonator
Any chance you could suggest dims for 2x chr70 per cab? I have 2 pairs of the german version, the omnes bb4.al, looking for a home. Would doubling up the drivers have noticeable benefits?
Thanks for all the great work!
btw, followed your (and wushiliu's) advice and picked up a little tpa3116 amp from ebay and it sounds great!
Hi xrk971,
Any chance you could suggest dims for 2x chr70 per cab? I have 2 pairs of the german version, the omnes bb4.al, looking for a home. Would doubling up the drivers have noticeable benefits?
Thanks for all the great work!
btw, followed your (and wushiliu's) advice and picked up a little tpa3116 amp from ebay and it sounds great!
Karlsonator with dual CHR70 Omnes
Giantstairs,
Glad you like the TPA3116D2 amp! It is the perfect amp for full range drivers as we hardly ever see the need for more than 40 or 50 watts/ch.
The dual CHR70 Omnes is an interesting pairing with the Karlsonator. The bezel on MA drivers is huge - if that was my one complaint, they should be smaller in the future (probably large size needed for strength since made of plastic?). The bezel is nearly 5 in in diameter which necessitates a scale on the Karlsonator to be at least 0.75x in order to accommodate the two driver bezels. This is not exactly a mini anymore at 22 in tall - but hey, the bass performance will amaze you in this box at that size. The optimized design ended up at 0.75x for length and depth (13.2 in deep) and 0.47x in width (7 in wide). It will be a tall aspect ratio cabinet. The drivers are connected in series as the Re is 3.6 ohms for a total 8 ohm nominal load.
The SPL vs Freq looks very good with an average SPL in the bass region of about 90dB at 2.83V and 1m. The -3dB point for bass extension is about 45 Hz which is very good.
The impedance looks very good for most amps and is flat in the HF region:
The cone excursion is manageable, if you have lof freq content, a high pass filter before the amp might be needed to stay below 4.5mm.
Finally, the impulse response is about as good as you can get - very clean tight dynamics. Drums, guitar, pianos should sound very crisp and lifelike.
I hope you build it - please post pics!
Giantstairs,
Glad you like the TPA3116D2 amp! It is the perfect amp for full range drivers as we hardly ever see the need for more than 40 or 50 watts/ch.
The dual CHR70 Omnes is an interesting pairing with the Karlsonator. The bezel on MA drivers is huge - if that was my one complaint, they should be smaller in the future (probably large size needed for strength since made of plastic?). The bezel is nearly 5 in in diameter which necessitates a scale on the Karlsonator to be at least 0.75x in order to accommodate the two driver bezels. This is not exactly a mini anymore at 22 in tall - but hey, the bass performance will amaze you in this box at that size. The optimized design ended up at 0.75x for length and depth (13.2 in deep) and 0.47x in width (7 in wide). It will be a tall aspect ratio cabinet. The drivers are connected in series as the Re is 3.6 ohms for a total 8 ohm nominal load.
The SPL vs Freq looks very good with an average SPL in the bass region of about 90dB at 2.83V and 1m. The -3dB point for bass extension is about 45 Hz which is very good.
The impedance looks very good for most amps and is flat in the HF region:
The cone excursion is manageable, if you have lof freq content, a high pass filter before the amp might be needed to stay below 4.5mm.
Finally, the impulse response is about as good as you can get - very clean tight dynamics. Drums, guitar, pianos should sound very crisp and lifelike.
I hope you build it - please post pics!
Attachments
Cool little project. I've got some EPI microtowers where one of the drivers is frozen, leaving me with three good ones to play with. I've also got a ton of scrap 1/4" ply sitting around so I could crank out a pair for nothing other than my time.
Only issue is that I don't know anything about the driver specs. All I know is that they're 4.5" (4" to outside edge of surround) CTS drivers that appear identical to Bose 901 series one drivers.
Since all my material is free I suppose I could just dive in blind and see how they turn out. Should I try half scale or slightly bigger for that extra half inch?
No experience building speakers but I've always thought Karlsons looked cool and the fact that it's full range means no extra parts and soldering required.
Only issue is that I don't know anything about the driver specs. All I know is that they're 4.5" (4" to outside edge of surround) CTS drivers that appear identical to Bose 901 series one drivers.
Since all my material is free I suppose I could just dive in blind and see how they turn out. Should I try half scale or slightly bigger for that extra half inch?
No experience building speakers but I've always thought Karlsons looked cool and the fact that it's full range means no extra parts and soldering required.
Aural Abrasions (I like that handle! 
):
If you think they are indeed the Bose 901 driver, I can sim that. When you measure the DC resistance, is it about 1 ohm? That will tell you it is a 901 driver. But otherwise, it may be hit or miss to build a box not knowing the parameters. You will just lose time and effort - although it may sound very good. Since you only have 3 drivers, I assume you only want a single driver version and not a dual driver version? Not knowing anything else about this driver, it may be a safe bet to build a 0.53x scale (15 in tall and 8.3 in deep) with a single driver but scale the width by 0.47x (7 in wide).
Regards,
X
If you had a Bose 901 driver and an amp capable of driving a 1 ohm load, here is how it would look at 0.71 volts drive (1 watt at 1 meter). Not too bad! Very flat response with great efficiency.
):If you think they are indeed the Bose 901 driver, I can sim that. When you measure the DC resistance, is it about 1 ohm? That will tell you it is a 901 driver. But otherwise, it may be hit or miss to build a box not knowing the parameters. You will just lose time and effort - although it may sound very good. Since you only have 3 drivers, I assume you only want a single driver version and not a dual driver version? Not knowing anything else about this driver, it may be a safe bet to build a 0.53x scale (15 in tall and 8.3 in deep) with a single driver but scale the width by 0.47x (7 in wide).
Regards,
X
If you had a Bose 901 driver and an amp capable of driving a 1 ohm load, here is how it would look at 0.71 volts drive (1 watt at 1 meter). Not too bad! Very flat response with great efficiency.
Attachments
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Karlsonator with dual CHR70 Omnes
Hi xrk,
Thanks for running that! In terms of size it seems a bit too big for a bookshelf, but too small for a floorstander. Would there be any gains for making it larger or should it be built on an empty (or sand filled) base to bring it up to listening height?
I'm planning on building with 10mm plywood or particle board, almost portable, compared to my fe165k bib's made with 22mm plywood.
Hi xrk,
Thanks for running that! In terms of size it seems a bit too big for a bookshelf, but too small for a floorstander. Would there be any gains for making it larger or should it be built on an empty (or sand filled) base to bring it up to listening height?
I'm planning on building with 10mm plywood or particle board, almost portable, compared to my fe165k bib's made with 22mm plywood.
Yes, it is an intermediate odd size. Keeping on floor improves bass (in fact, the sims include effect of floor loading). Note that the drivers angle up and even a 15 in tall Karlosnator sounds quite nice on the floor. The sound stage will appear to be low but if that doesn't bother you - the sound is aimed up - like a stage monitor for a band. Raising on stands is an option at cost of decreased bass extension.
I remember flipping through a NME mag in my youth and coming across an industrial/metal compilation CD of some kind titled Aural Abrasions, always thought it was a cool title.Aural Abrasions (I like that handle!
If you think they are indeed the Bose 901 driver, I can sim that. When you measure the DC resistance, is it about 1 ohm? That will tell you it is a 901 driver. But otherwise, it may be hit or miss to build a box not knowing the parameters. You will just lose time and effort - although it may sound very good. Since you only have 3 drivers, I assume you only want a single driver version and not a dual driver version? Not knowing anything else about this driver, it may be a safe bet to build a 0.53x scale (15 in tall and 8.3 in deep) with a single driver but scale the width by 0.47x (7 in wide).
Regards,
X
If you had a Bose 901 driver and an amp capable of driving a 1 ohm load, here is how it would look at 0.71 volts drive (1 watt at 1 meter). Not too bad! Very flat response with great efficiency.
The original Bose 901 and series two used 8ohm drivers. I just went out to the garage and checked two of them and they read 7.5 and 7.1ohms.
http://www.diyaudio.com/forums/multi-way/243702-describe-original-bose-901-driver.html
I've sent an email to Human Speakers to see if he can provide any insight into the specs. He sells exact replacements so hopefully he doesn't mind handing out the specs.
Only thing I could find on the driver was 5011 on the back with 137 7411 underneath. The markings on the second one were too faint to make out except for the 5011.
Human speakers, ah Huw Powell. He's right down the road from me, next door to my auto mechanic. I've dropped by numerous times but he's never there. Oh well. Curious guy. Keeps detailed records of temps and snowfall and who knows what else. My mechanic seems to like him. Huw got his start at Genesis Physics Corp. which arose out of EPI. Hence the connection.
PS - don't hold your breath waiting for a reply from Huw. Things happen slowly there, it's like island time, but in the frozen white of NH.
PS - don't hold your breath waiting for a reply from Huw. Things happen slowly there, it's like island time, but in the frozen white of NH.
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I never heard of this company until now.
HUMAN Speakers: Model Guide
Human Speakers sells a $654,321.99 line array made of granite!!? Is this real?
HUMAN Speakers: Model Guide
Human Speakers sells a $654,321.99 line array made of granite!!? Is this real?
This is better value for money
Battery-Tube-Only-Headphones-Amplifier-for-Sennheiser-HD-580-600-650-Beyer-DT880 for a mere USD 70,000.- on eBay.
From the description:
Pleiades Electra, possibly the most transparent amplifier on earth. No other components except 2 tubes for both (stereo) channels. For the schematic Only please visit my other items.
An electron tube on its own has a flat frequency response from 0Hz to many MHz. Surrounding components restrict this and limit the magic of music in other ways too. This is possibly the first amplifier on earth using electron tubes and only.
Since the signal passes through an electron tube and nothing else, the amplifier is possibly the closest there is to a wire with power gain!
Gain being fixed it must be connected to a passive preamplifier or a source that has variable output. Volume control may be added on your request.
Item may not look exactly the same, reserving the right to make revision changes. Handling time approximately 30 days. This amplifier is only suitable for high impedance stereo headphones such as the Sennheiser HD-580, Beyer DT880 or equivalent..
Specifications:
Bandwidth <<0.000001Hz to >>MHz (DC to RF)
12V extremely low noise battery operation
Power consumption < 7W
Input impedance >>MOhm
No resistors, potentiometers
No capacitors
No transformers, inductors
No solid state, diodes, transistors, FETs, ICs
The signal is amplified by only 2 electron tubes in class A.
Only suitable for headphones with impedance >150, <600 Ohms
Caution: Headphones can damage hearing at high levels. Please make shure you attenuate your source signal adequately before sending to this headphone amplifier.
Picture attached of suggested headphones
Battery-Tube-Only-Headphones-Amplifier-for-Sennheiser-HD-580-600-650-Beyer-DT880 for a mere USD 70,000.- on eBay.
From the description:
Pleiades Electra, possibly the most transparent amplifier on earth. No other components except 2 tubes for both (stereo) channels. For the schematic Only please visit my other items.
An electron tube on its own has a flat frequency response from 0Hz to many MHz. Surrounding components restrict this and limit the magic of music in other ways too. This is possibly the first amplifier on earth using electron tubes and only.
Since the signal passes through an electron tube and nothing else, the amplifier is possibly the closest there is to a wire with power gain!
Gain being fixed it must be connected to a passive preamplifier or a source that has variable output. Volume control may be added on your request.
Item may not look exactly the same, reserving the right to make revision changes. Handling time approximately 30 days. This amplifier is only suitable for high impedance stereo headphones such as the Sennheiser HD-580, Beyer DT880 or equivalent..
Specifications:
Bandwidth <<0.000001Hz to >>MHz (DC to RF)
12V extremely low noise battery operation
Power consumption < 7W
Input impedance >>MOhm
No resistors, potentiometers
No capacitors
No transformers, inductors
No solid state, diodes, transistors, FETs, ICs
The signal is amplified by only 2 electron tubes in class A.
Only suitable for headphones with impedance >150, <600 Ohms
Caution: Headphones can damage hearing at high levels. Please make shure you attenuate your source signal adequately before sending to this headphone amplifier.
Picture attached of suggested headphones
Attachments
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Are you sure that isn't a typo and they aren't asking $70? Anyhow, if you want a really cool electron tube amp, check out traveling wave tube amplifiers (TWTA). 94% efficiency vacuum tubes that are used to amplify satellite transponders (kW levels) for DISH network, broadcast and cable TV, etc (on the space craft).
I just checked ebay. It isn't a typo. This might be a good way to make a living. Now, where do I find those great headphones?
Roger
Hi X,
Starting to cut foam core for your Mini-K. Question: Did you put adhesive between the two layers used in the driver baffle? If so, then what adhesive?
Building just one as a test, then I'll decided on the next step--build another in foam core or build two from 1/4" plywood.
Many thanks for the hours of fun you've given me!
Cheers, Jim
Starting to cut foam core for your Mini-K. Question: Did you put adhesive between the two layers used in the driver baffle? If so, then what adhesive?
Building just one as a test, then I'll decided on the next step--build another in foam core or build two from 1/4" plywood.
Many thanks for the hours of fun you've given me!
Cheers, Jim
Jim,
Great to see you are about to start on this adventure! If you have time glue them together with PVA. Otherwise use hot melt glue and avoid putting hot melt where the cut lines for the driver holes will be (razor has hard time with glue). Offset the panels a bit leave a ledge for the front upper panel to wedge into for an secure fit. You should have non problem at all with this.
Good luck!
Great to see you are about to start on this adventure! If you have time glue them together with PVA. Otherwise use hot melt glue and avoid putting hot melt where the cut lines for the driver holes will be (razor has hard time with glue). Offset the panels a bit leave a ledge for the front upper panel to wedge into for an secure fit. You should have non problem at all with this.
Good luck!