AudioCircle
Industry Circles => Hollis Audio Labs => Topic started by: HAL on 13 Oct 2017, 08:57 pm
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Have a request for a dspMusikLCD digital crossover for the JBL M2 speaker system to use instead of the Crown amps the original crossover was created to run. This will be for a demo once the system is setup.
Have the prototype block diagram completed and running. Next will be testing the response to see if this matches the reference curves. Will setup Pocket CLIO for taking the response data.
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Have a JBL M2 owner that is interested in a demo, so will finish the setup and measurements for the system and get it ready to ship for listening trials.
Once the final crossover is decided, will post response plots of the dspMusikLCD version.
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Rich, you should consider sharing this info with the folks at Lansing Heritage. There are members there building diy M2s. You should probably introduce yourself to them as most there won't have any idea what you do. http://www.audioheritage.org/vbulletin/
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Rusty,
Thanks for the info.
If the JBL M2 demo goes well, then will post on the site. I have no way to listen to the M2 speaker system, so if the results are positive, then would make sense to let them know.
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M2 DIY movement was stifled when JBL shut down the parts supply to non M2 owners. :cry:
This might help you Rich, fwiw: JBL M2 crossover settings (http://goo.gl/GdfQ7N)
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Rich,
Thanks! :)
I used that to make the prototype, so should be close. Have to use a different approach for some of it as it is proprietary to Crown. Will use the alternatives suggested in the paper.
This should be interesting!
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Have the latest dspMusikLCD demo unit in and ready for JBL M2 trials when someone has interest.
Once I flash the program, the unit is stand alone and works with the remote control for most functions users want. Input selection (analog, USB and S/PDIF), mute, volume control, ADC and DAC filters, ADC and DAC voltage levels. System comes with the remote control for use.
I have a set of balanced cables for system connection with the system for trials. You just need the amps and speakers.
Happy Holidays!
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Is there a way to just use the DSP only so an external dac can go direct?
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No. The four DAC's are on the dspMusikLCD 2x8 motherboard.
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What are the source inputs?
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Tom,
Balanced Analog, USB2 and S/PDIF inputs on the system. All selected by the remote control or front panel control.
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Jason, With 2 balanced inputs coming from your DAC and DSPMusik's 4 channel DAC outputs, this would be essentially the same as a BSS BLU-50.
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I will propose an idea.
I send the demo unit to you both and let you try it for 2 weeks. Then send to the other one. I only have one unit available for demo, so serial trials will work.
Will be out until 22 Jan, so gives some time to get ready if needed.
I just need to know cables, as the unit has 1/4" TRS connectors, so I send TRS to XLR balanced cables for I/O. If single ended, will send adapters.
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I will propose an idea.
I send the demo unit to you both and let you try it for 2 weeks. Then send to the other one. I only have one unit available for demo, so serial trials will work.
Will be out until 22 Jan, so gives some time to get ready if needed.
I just need to know cables, as the unit has 1/4" TRS connectors, so I send TRS to XLR balanced cables for I/O. If single ended, will send adapters.
It's all balanced I/O (XLR).
I couldn't do anything until after that time anyway. I need 4 identical amp channels of sufficient power available, which is still in the works.
Let's just stay in contact via email go from there.
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Tom,
Ok, will be down in FL next week in the Orlando area. Hope everything is going well.
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Tom,
Ok, will be down in FL next week in the Orlando area. Hope everything is going well.
I'm 3-4 hours southwest of you, enjoy :thumb:
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Yeah let's see in a couple months where we're at but I should be able to try it. :thumb:
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Tom,
Thanks!
Jason,
Ok, keep me posted when you are ready.
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Have another person interested in the JBL M2 digital crossover, so will get the dspMusikLCD unit programmed for response testing as a comparison to the reference frequency response plot in the document.
Will post them both as a comparison once completed.
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Here is the results of the dspMusikLCD 2x8 digital version of the JBL M2 digital crossover from the reference document posted earlier with the frequency response plots.
Problem is the scales on the original response graphs are missing in the PDF, so no absolute reference other than the data in the document.
Looks close from what data I can check. Now for someone with JBL M2's to check the sound.
(http://www.audiocircle.com/image.php?id=174996)
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The first demo of the dspMusikLCD for JBL M2 speakers is getting ready to ship out this week.
Will be interesting to get feedback on how it sounds in the system.
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The first dspMusikLCD 2x8 programmed for the JBL M2 speakers is ready with the kit of remote control and cables needed to run in the system with fully balanced connections.
Will ship out Friday for the demo.
(http://www.audiocircle.com/image.php?id=175083)
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The dspMusikLCD 2x8 for the JBL M2 speakers is on the way for the demo. Looking forward to listening comments.
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The dspMusikLCD 2x8 has arrived for demo with the JBL M2 speakers.
Will be interesting to get the feedback on the listening trials.
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The dspMusikLCD 2x8 for the JBL M2's was installed yesterday and listening has begun.
Hope he enjoys the time with it running his setup.
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The listening trials show that the document that was published for the JBL M2 speaker digital crossovers are different than the original versions.
I asked in the JBL forum about the original response graphs to see if anyone still has them with the scales intact. Would need those to see what the difference is, or measure a pair of original crossovers. The tweeter response it to hot even with the gains shown.
Until then, the system is on hold.