Hopkins' System
- Thread starter hopkins
- Start date
0.45 according to the specs.
W8-2145 - 8" Paper Full Range - TB SPEAKER CO., LTD.
www.tb-speaker.com
What is the amp damping factor?0.45 according to the specs.
W8-2145 - 8" Paper Full Range - TB SPEAKER CO., LTD.
I've asked the manufacturer for more information. On many aspects, it works differently from conventional amplifiers, so it's best to have their explanations.
They basically confirmed what I had written above:
- frequency response of Tang Band W8-2145 is specified from 40Hz, but these are "ideal" conditions. You can see from their FR graph (in the link I send) that bass starts to roll-off from 100hz and you have around 10db less at 40hz
- baffle geometry, and room acoustics has to be taken into account as well.
The difficulty in assessing an amplifier is that you are obviously listening to the speakers and the room, with their own limitations. It would be great if I could try the amplifier in a variety of systems/rooms, but this is difficult to organize (for me). Anyone living in Paris who would be curious to test it can message me!
THere aren't some good shops in Paris that would allow you to demo amps at home? The reason I mention damping factor is that with open baffle a high damping factor will act to reduce bass output even further. It's a lot like a horn in that regard. With my Odeons, they have just enough bass when using an amp with little to no self-damping (the horn is pretty effective in damping and the drivers used are very low Qts). If I put a class D or even a tube amp with a fair amount of negative feedback (to bring down the output impedance and increase the damping factor) the bass dries up and the speaker then sounds very thin. Your speakers, while very articulate, are on the leanish sounding side and that is partially the baffle but could also be the effect of an amp with a high damping factor on speakers that don't really want that.
The amp's output is 2 ohm, and my speakers are wired 8 ohm. The speaker steering mechanism, and the whole amp itself, is really different from conventional amps, so I would be hesitant to draw any conclusions. Rather than testing my speakers with a different amplifier, which is complicated to do - I would also need a comparable DAC + preamp - I would find it easier, and probably more relevant for others - to test the amplifier in someone else's complete system.
From my personal standpoint, I will work on improving the speakers - I don't plan on going back to other components (DAC/preamp/amp/cables). So I have little motivation to do complex amp comparisons in my home. If others are curious about how the amp works with their speakers, against their existing components, I would be more than happy to take the amp over for a spin (it is light).
2 ohms? THat is like a SET output impedance...are you sure because i know of no SS based amps with such a high output impedance.
Yes, this is the output impedance. Honestly, the technical aspects are beyond me, but it does not work like any other amplifier.
Here is the website page corresponding to the amp - some information is given in the user documentation ("user guide" button at the bottom of the page). If you have questions, don't hesitate to mention them here and perhaps I can get some clarifications from them, it could be of benefit to others to share them.
PowerDAC-SX + IRC – ECdesigns
www.ecdesigns.nl
Lunch break... Playing around with speaker placement and listening with my ceiling panels (that I readjusted)
Japanese big band is better recorded, but it still can't compete with Ellington
Check out the chase between Lawrence Brown (trombone) and Johnny Hodges (saxophone) starting at 1:25. Nice vocals by Ivie Anderson. Recorded in 1940...
Very satisfying sound. Tweeters to be added next.
Japanese big band is better recorded, but it still can't compete with Ellington
Check out the chase between Lawrence Brown (trombone) and Johnny Hodges (saxophone) starting at 1:25. Nice vocals by Ivie Anderson. Recorded in 1940...
Very satisfying sound. Tweeters to be added next.
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Here is the Kenichi Tsunoda recording with my Tascam DR40X (build-in microphones):
Here is the source: https://open.qobuz.com/track/48912243
And while we are at it, Miles Davis - Freddie Freeloader - mono recording:
Source is a file being played from a RaspberryPi (with MPD software).
Recording level may be a tad high.
Here is the source: https://open.qobuz.com/track/48912243
And while we are at it, Miles Davis - Freddie Freeloader - mono recording:
Source is a file being played from a RaspberryPi (with MPD software).
Recording level may be a tad high.
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Some live music tonight - Le Duke Orchestra:
Nice performance, including parts of the Nutcracker Suite and the Harlem Suite.
Once again a reminder that home audio and live music are two very different things, for those who had forgotten
Nice performance, including parts of the Nutcracker Suite and the Harlem Suite.
Once again a reminder that home audio and live music are two very different things, for those who had forgotten
Have you not heard a home audio system approach a live performance?Some live music tonight - Le Duke Orchestra:
Nice performance, including parts of the Nutcracker Suite and the Harlem Suite.
Once again a reminder that home audio and live music are two very different things, for those who had forgotten
One year at Munich the Living Voice system approached live...it was jaw-dropping. Also, in 2019 the Aries Cerat system on a particular flamenco track did approach...about the only two times I have heard it truly get close.
I am testing the WiiM Pro and so far I am very satisfied.
I use it as a fancy Chromecast and "switch" (see below). It is connected to my powerDAC-SX through it's Toslink output.
1) Qobuz
I like using Qobuz with its own app on my Android phone. The WiiM Pro (unlike the WiiM mini) is a Chromecast "receiver" so I can simply select it in the Qobuz app on my phone.
In that configuration the resolution is limited to 96kHz, but the sound is just as good in CD quality (16/44), and that is how I am using it.
The sound is no different playing Qobuz with WiiM's app (which supports 192kHz).
I also have a Spotify account (family plan) and the connection to the WiiM pro from their app works flawlessly.
2) Switch
The WiiM Pro has a Toslink input as well, which I use to connect my RaspberryPi, as I play music in my personal library using a custom app.
The digital signal coming into the Toslink input is passed-through "as-is" to the Toslink output. The WiiM can be configured to detect a signal on the Toslink input and automatically play it. So it is very easy to switch back and forth been two sources.
I can also compare the sound between Qobuz and the same (purchased) files played from my RaspberryPi, and there is no perceivable difference in SQ.
I have not checked yet that the signal is bit-perfect in this configuration (bit-perfect output from RaspberryPi -> WiiM Toslink input -> WiiM Toslink output = bit perfect?). The powerDAC-SX has a bit perfect tester, so I will be doing that, but I would be surprised if it is not positive.
This is my experience using these different sources and formats with the powerDAC-SX - it works for me, but perhaps more discerning ears would disagree?
I use it as a fancy Chromecast and "switch" (see below). It is connected to my powerDAC-SX through it's Toslink output.
1) Qobuz
I like using Qobuz with its own app on my Android phone. The WiiM Pro (unlike the WiiM mini) is a Chromecast "receiver" so I can simply select it in the Qobuz app on my phone.
In that configuration the resolution is limited to 96kHz, but the sound is just as good in CD quality (16/44), and that is how I am using it.
The sound is no different playing Qobuz with WiiM's app (which supports 192kHz).
I also have a Spotify account (family plan) and the connection to the WiiM pro from their app works flawlessly.
2) Switch
The WiiM Pro has a Toslink input as well, which I use to connect my RaspberryPi, as I play music in my personal library using a custom app.
The digital signal coming into the Toslink input is passed-through "as-is" to the Toslink output. The WiiM can be configured to detect a signal on the Toslink input and automatically play it. So it is very easy to switch back and forth been two sources.
I can also compare the sound between Qobuz and the same (purchased) files played from my RaspberryPi, and there is no perceivable difference in SQ.
I have not checked yet that the signal is bit-perfect in this configuration (bit-perfect output from RaspberryPi -> WiiM Toslink input -> WiiM Toslink output = bit perfect?). The powerDAC-SX has a bit perfect tester, so I will be doing that, but I would be surprised if it is not positive.
This is my experience using these different sources and formats with the powerDAC-SX - it works for me, but perhaps more discerning ears would disagree?
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Here's an interesting experiment, placing a lot of absorption on my couch behind and around my listening position.
Video 1 without absorption:
Video 2 with absorption:
The two videos were taken a few days apart and were not recorded at the same volume level. I think the reduction in reverberation is clearly heard, with a "drier" sound in the second video. The absorption may be uneven over the frequency range - I will check with some measurements, even though I don't plan on keeping this "extreme" absorption.
Video 1 without absorption:
Video 2 with absorption:
The two videos were taken a few days apart and were not recorded at the same volume level. I think the reduction in reverberation is clearly heard, with a "drier" sound in the second video. The absorption may be uneven over the frequency range - I will check with some measurements, even though I don't plan on keeping this "extreme" absorption.
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