Please bring whatever you like.
Just note its hard to entertain a group with a pair of headphones.
Most get to stand around while one listens, so it may not be an extended evaluation, or maybe I’m wrong (again) and there is more interest. Kind of like trying to feed a group with one cupcake........
Just note its hard to entertain a group with a pair of headphones.
Most get to stand around while one listens, so it may not be an extended evaluation, or maybe I’m wrong (again) and there is more interest. Kind of like trying to feed a group with one cupcake........
Well my headphone amp is the home office system. It drives a 1/4" jack directly and it also drives RCA out with a 100 ohm current limit resistor. When I want to use it as a headphone amp, I just shut down the power amp. So it perform dual duties. The Khadas is the source for the headphone amp. If I can find an extra type C cable, I will make a Y connector to feed the Khadas with a low noise 5 V supply as opposed to using what is coming out the USB from the PC. I imagine different results will come from different PCs and their respective noise levels on their USB outputs. The other thing is that USB 3.1 on newer motherboards sound better than older USB2.0 on older motherboards. This could be a power issue where USB 3 has better power capabilities.
Some can even bring a USB cable to see if different cables sound differently. We need a USB to type C for the Khadas, the only one I have is what came with the Khadas. Do USB cables make a difference....OH yes, and it was a shocker when I tried it on my main DAC rig. It could be that it affects the noise level in the power supply to the XMOS card.
Some can even bring a USB cable to see if different cables sound differently. We need a USB to type C for the Khadas, the only one I have is what came with the Khadas. Do USB cables make a difference....OH yes, and it was a shocker when I tried it on my main DAC rig. It could be that it affects the noise level in the power supply to the XMOS card.
Chris, can you bring a couple of subs you had once, I can bring some older small Mirages M2s and we could put together a full range sound system for comparison as opposed to the massive horns. I also have REW and a UMIK to adjust levels for integration.
I can also bring and compare digital through the ages. .....an ASSEMBLAGE DAC-2 with the factory mods - older than 20 years. It could be interesting just to see how much further or still how close it is now. 20 years ago, that Assemblage DAC was close to $1000 as opposed to the Khadas now for $99.
I can also bring and compare digital through the ages. .....an ASSEMBLAGE DAC-2 with the factory mods - older than 20 years. It could be interesting just to see how much further or still how close it is now. 20 years ago, that Assemblage DAC was close to $1000 as opposed to the Khadas now for $99.
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There are subs still in the shop, because I was too lazy to take them hone last time.
The preamp this time is a Toshiba 2SK170/2SJ74 all jfet cascode direct coupled single ended design. Not sure if Rick is bringing a new Cordell Hafler power amp.
I have a Borbely all fet Hafler.
Digital source is an Oppo with USB drive with Exact Audio transfers of CD source material and 150 high def 24/96 and 24/192 mostly classic rock and blues albums.
The shop JBL speakers with polypropylene cap crossover aren’t as resolving as my home electrostatic system, but It isn’t being moved. I hear bigger component differences on them
The preamp this time is a Toshiba 2SK170/2SJ74 all jfet cascode direct coupled single ended design. Not sure if Rick is bringing a new Cordell Hafler power amp.
I have a Borbely all fet Hafler.
Digital source is an Oppo with USB drive with Exact Audio transfers of CD source material and 150 high def 24/96 and 24/192 mostly classic rock and blues albums.
The shop JBL speakers with polypropylene cap crossover aren’t as resolving as my home electrostatic system, but It isn’t being moved. I hear bigger component differences on them
Really looking forward to see you guys again this Sunday!
Just wondering if anyone in the group is willing to show this newbie how to measure noise, frequency response, and distortion of a preamp - I built a simple one from a kit and would like to learn how to do measurement. I understand that I probably need a signal generator and an oscilloscope. Unfortunately, I don't have any instruments and except DMMs
. Thus, the "teacher " would have to provide the instruments too.
Regards,
Just wondering if anyone in the group is willing to show this newbie how to measure noise, frequency response, and distortion of a preamp - I built a simple one from a kit and would like to learn how to do measurement. I understand that I probably need a signal generator and an oscilloscope. Unfortunately, I don't have any instruments and except DMMs
. Thus, the "teacher " would have to provide the instruments too. Regards,
I'll bring the Amber 3501 Audio test set and give you a hand with testing. Not sure about cabling, what does it use for jacks?
I managed to get a couple of Hafler DH-200's last week, I've modified the DH-220C pcb to bring it up to an A1 revision, working on putting it into the Hafler chassis. I have only one pcb so can only do one channel, but good enough for proof of concept.
Maybe Dave will want to mod his boards to bring them up to the current revision, I can show what Bob Cordell has done & bring along the parts. Also designed a small pcb for output stage wiring simplification, added filtering, zobel network, gate resistors, I'll bring along the parts.
I managed to get a couple of Hafler DH-200's last week, I've modified the DH-220C pcb to bring it up to an A1 revision, working on putting it into the Hafler chassis. I have only one pcb so can only do one channel, but good enough for proof of concept.
Maybe Dave will want to mod his boards to bring them up to the current revision, I can show what Bob Cordell has done & bring along the parts. Also designed a small pcb for output stage wiring simplification, added filtering, zobel network, gate resistors, I'll bring along the parts.