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Update on Caver undspeakers

March 12th, 2017, 12:31 pm

Alan Bromborsky (Brombo) handed over to me a couple weeks a go a pair of Calver ALS Original's, probably 1988 vintage. Stock these thing are a power black hole and I had nothing that could drive them past a whisper. What I could hear was pretty bad. I found some bad solder joints on two non working woofers and one rattling woofer's cone was delaminating from the honeycomb disk. With that fixed tings got a little better but I was not going to go shopping for a couple of horsepower amps.
Alan suggested to bi-amp with electronic xover. I have gon this way in the past with the Maggies and never got satisfactory results. Alan suggested the miniDSP-HD. I had tried the original minDSP and could not get past the digital artifacts, and was assured he new HD piece was much better. From a technological point of view this is one neat device. The software interface is really easy and you can adjust xover points and eq on the fly while listening. But......................
It has the same big HiFi glassy edgy sound of the modern commercial equipment out there.
I really need the incredibly variable eq on the woofers as you can see in the screen grab. So the DSP is needed there but since 90% of the music comes from the ribbons (xover point is a low 150hz) I need something better for the Ribbons. I am looking a few options.
The really amazing part of this is I can drive these speaker to well over 100db cleanly with 200 watts per channel. The junky amp I am using for the woofers have power meters and when pushing 106db peaks the meters rarely went over 100 watts.

Re: Update on Caver undspeakers

March 12th, 2017, 12:49 pm

Brombo again. As an alternative to the miniDSP look at -

http://rtaylor.sites.tru.ca/2013/06/25/ ... are-howto/

Also there is windows software for using your sound card as an dsp crossover


I don't have any opinion on the windows software since I don't use windows.

I hope to eventually replace the miniDSP I am using with the cbt36k's with my computers soundcard (Xonar D2) and appropriate
dsp software but the sound server (also video) program I am using is Kodi and I cannot redirect the
audio output from Kodi to a dsp program via the command line so I have to learn how to use the ladspa
filters for alsa so the dsp processing looks like and alsa audio output device that I can select from Kodi.

Re: Update on Caver undspeakers

March 12th, 2017, 1:17 pm

I think my complaint is the "digital" part. I feel I need to go analogue on the ribbons.

Re: Update on Caver undspeakers

March 12th, 2017, 2:13 pm

Do you mean that to you no digital source (CD's, .wav, .flac, .mp3, .etc) that has a DAC sounds right to you? My complaint with the miniDSP 2x4 HD is that for my use it requires an ADC (I am using the analog inputs since I am running Linux). Can you use the digital inputs (optical and usb only for windows) on the miniDSP 2x4 HD and see if it sounds any different?

Re: Update on Caver undspeakers

March 12th, 2017, 3:34 pm

I do listen to digital source. I have music files on a NAS, and use a Raspberry Pi running Rune software as a player into my Twisted Pear Buffalo DAC vis USB. I accept the sound of a digital source as long as its musical. My serious listening is pure analog via vinyl set up.
My problem is when I inject DSP in the system, the sound becomes more HiFi than real. It has a glassy quality that chases me out of most hi-end megabuck systems I have heard at RMAF and Axpona.
I think I get the Carver ASL's to be musical if I get a decent analog xover on the ribbons, since the ribbons produce 90% of the sound coming from the speakers.

Re: Update on Caver undspeakers

March 12th, 2017, 4:01 pm

This is what we used in the DCAudioDIY room at CAF in 2016....



Re: Update on Caver undspeakers

March 12th, 2017, 5:02 pm

Hey Paul!

Do you want try the auto-transformers? You can go in either direction with them -- current to volts -or- volts to current.

Re: Update on Caver undspeakers

March 12th, 2017, 7:17 pm

Thanks, you have mentioned the Behringer before and its on the list but I found a linkwitz 24db/octave
From china with replaceable chips for $30. Does not have flashing leds or dancing girls which is more my speed. I have a few OPA chips to replace the standard chips that come with it. I am just waiting for a reply that I can configure this unit for 150hz which is outside the norm

If the Carver ASL's are keepers then your autoworkers will come into play when the Hurricanes are up and running

Re: Update on Caver undspeakers

March 13th, 2017, 8:31 am

Yes. A cool way to get current while the amplifiers just have to provide voltage. They could work with your SS amps. Without having to source heavy current you gain headroom from the power supply that you would have normally. Just a thought.

Re: Update on Caver undspeakers

March 13th, 2017, 10:08 am

I think you would be surprised how they sound even with the crappy sounding DSP. Not as musical as the maggies were but not terrible. A better analog electronic xover should be an improvement. If it does then maybe this will be the incentive I need to dig back into the Hurricanes and dump the mediocre Odyssey Kismet's Klause built for me
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