Sorry for the intrusion and off topic post but I have seen a few people now criticise Ian's FIFO outside of his thread with baseless claims.
EDIT: moved my post to the FIFO thread where it is more on-topic - http://www.diyaudio.com/forums/digi...ultimate-weapon-fight-jitter.html#post3369233
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I bought the DDX320 to try to do what soundcheck proposed, it was supposed to be sacrificed... That is why I was kind of unhappy-as I said it died before I did anything to it, that was my disappointment 
I wasn't trying to bash the efforts of the guys who made it, I was simply wondering why some who can create a product like that and has the ability to program and design does not spend a little more time to make it right... I hope I did show respect by buying it and using two nice magnesium-alloy boxes to house the batteries and the designed recharger, I was hoping that if it is going to die it will be from something I have done to it... Apologies for the spam, next post from me will be on sound quality
I wasn't trying to bash the efforts of the guys who made it, I was simply wondering why some who can create a product like that and has the ability to program and design does not spend a little more time to make it right... I hope I did show respect by buying it and using two nice magnesium-alloy boxes to house the batteries and the designed recharger, I was hoping that if it is going to die it will be from something I have done to it... Apologies for the spam, next post from me will be on sound qualityWOW!
Cross-post offtopic bashing.... I as a "noob" in this forum can only get the impression that there must be something fishy with aforementioned FIFO if other forumites deem it necessary to hijack other threads and flame a poster for voicing his opinion. If said FIFO is soooo good then in my opinion it would speak for itself and not need active defending in a thread where (most likely) nobody would really care if product x has been questioned..... at the moment the whole fuss is down to 2 posters, if not alter-ego accounts
People, get a life, relax and listen to whatever floats your boat...
Cross-post offtopic bashing.... I as a "noob" in this forum can only get the impression that there must be something fishy with aforementioned FIFO if other forumites deem it necessary to hijack other threads and flame a poster for voicing his opinion. If said FIFO is soooo good then in my opinion it would speak for itself and not need active defending in a thread where (most likely) nobody would really care if product x has been questioned..... at the moment the whole fuss is down to 2 posters, if not alter-ego accounts
People, get a life, relax and listen to whatever floats your boat...
I didn't even critizise that project itself. How could I. I don't even own that product. I just received vague answers in the past.
Both of the guys that posted here are close followers and main posters over there and try to put my comments out of context.
I'm obviously writing too much. People can pick and choose what fits best.
I left a comment over there. I don't have problems to start up a discussion.
Sorry HifiMeDiy and folks over here to cause that trouble. It hasn't been my intention.
Both of the guys that posted here are close followers and main posters over there and try to put my comments out of context.
I'm obviously writing too much. People can pick and choose what fits best.
I left a comment over there. I don't have problems to start up a discussion.
Sorry HifiMeDiy and folks over here to cause that trouble. It hasn't been my intention.
DDX V2 - outputstage part II.
The missing Zobels for channel 1 and 2 I mentioned some posts earlier are actually missing snubbers. These are meant for protecting the STM508 mosfets from the reactance (nasty spikes) of the output coils.
Why did they take them out on channel 1 and 2? Hmmh.
BUUUT. Surprise Surprise.
I just figured - after concentrating mainly on channel 1 and 2 all the time - that the bass channel 3 seems to be built according to datasheet!?!?
including snubber, decoupling and identical cap values where expected and also bridges both channels of the 2nd STA508.
Channel 1 and 2 seems to be done completely different when it comes to filters. I'm a bit confused.
I wrote them a mail - to take it offline. I'd like to hear what they say about it. Perhaps I missed something.
Cheers
The missing Zobels for channel 1 and 2 I mentioned some posts earlier are actually missing snubbers. These are meant for protecting the STM508 mosfets from the reactance (nasty spikes) of the output coils.
Why did they take them out on channel 1 and 2? Hmmh.
BUUUT. Surprise Surprise.
I just figured - after concentrating mainly on channel 1 and 2 all the time - that the bass channel 3 seems to be built according to datasheet!?!?
including snubber, decoupling and identical cap values where expected and also bridges both channels of the 2nd STA508.
Channel 1 and 2 seems to be done completely different when it comes to filters. I'm a bit confused.
I wrote them a mail - to take it offline. I'd like to hear what they say about it. Perhaps I missed something.
Cheers
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yes that would be interesting to know why they did not implement them.
My Remote problems are now reduced to one, the subwoofer volume control only works in the "vol-" direction, "vol+" does absolutely nothing... unless.... I default all settings and go directly to the subwoofer volume feature, then I can go up and down as I please. As soon as I use the vol control for, well, the "normal" volume, I can only turn the sub down not up...
My Remote problems are now reduced to one, the subwoofer volume control only works in the "vol-" direction, "vol+" does absolutely nothing... unless.... I default all settings and go directly to the subwoofer volume feature, then I can go up and down as I please. As soon as I use the vol control for, well, the "normal" volume, I can only turn the sub down not up...
I did some filter calculations ( at least I tried to )
What happens if they reduce the butterworth filter cap from 0.47uf to 0.1uf?
1. They'll increase the cutoff frequency from e.g. 22 to 47khz at L=44uH and
RL=8R.
That's perhaps not that critical.
2. They also lower the Q of the filter. That's probably pretty positive in this case.
In the case of C=0.47 the filter was underdamped, which caused peaking in
the highs. Getting the Q lower lowered the peaking. Still not perfect, but better.
3. On the woofer amp all that shouldn't matter. That's why they left it the way it
was.
That could be an explanation. Or complete nonsense.
In my case I lowered the stock coil values to 10uH each. That means I end up at an even lower Q and higher cutoff frequency.
Cheers
)What happens if they reduce the butterworth filter cap from 0.47uf to 0.1uf?
1. They'll increase the cutoff frequency from e.g. 22 to 47khz at L=44uH and
RL=8R.
That's perhaps not that critical.
2. They also lower the Q of the filter. That's probably pretty positive in this case.
In the case of C=0.47 the filter was underdamped, which caused peaking in
the highs. Getting the Q lower lowered the peaking. Still not perfect, but better.
3. On the woofer amp all that shouldn't matter. That's why they left it the way it
was.
That could be an explanation. Or complete nonsense.
In my case I lowered the stock coil values to 10uH each. That means I end up at an even lower Q and higher cutoff frequency.
Cheers
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I recently bought one of the Hifimediy amps (version 2.1) and was very happy with it driving 2-way tannoys (@ 8 ohms). Very detailed, precise amp.
However, I dug my old set of B&W Concept 90's (CM1 & CM2) out and felt that the amp was a little underpowered for those speakers.
I checked out the ST chips and found the STA517B was pretty much a direct drop-in "upgrade" - This gives 175w @ 8-ohms rather than the 75w @ 8-ohms from the STA510A chips. It does require more voltage ~57v max but I'm running it at 36v as I was on the original chip and seems to be approx. 10-15db louder from my tests (with the B&W's and amp at -17db volume) - Quick, easy upgrade.
This is great as the amp feels more than capable of driving the speakers now. Since the amp is only working at ~65% now (36v) it's in its sweet spot rather than driving it to 95-98%. More headroom and the whole "balance" of the frequency range sounds more linear, more appealing - I know technically it should sound the same but there's definitely a more "natural" and perhaps "weighty" output from it.
If you have re-flow capabilities I'd highly recommend this simple mod! Obviously the chip isn't being used to its full potential at this voltage but it's running at a nice level. Increasing the voltage means changing out a good few components on the board but I haven't really looked into that yet (and perhaps changing the sub output chip although that's just the same process).
However, I dug my old set of B&W Concept 90's (CM1 & CM2) out and felt that the amp was a little underpowered for those speakers.
I checked out the ST chips and found the STA517B was pretty much a direct drop-in "upgrade" - This gives 175w @ 8-ohms rather than the 75w @ 8-ohms from the STA510A chips. It does require more voltage ~57v max but I'm running it at 36v as I was on the original chip and seems to be approx. 10-15db louder from my tests (with the B&W's and amp at -17db volume) - Quick, easy upgrade.
This is great as the amp feels more than capable of driving the speakers now. Since the amp is only working at ~65% now (36v) it's in its sweet spot rather than driving it to 95-98%. More headroom and the whole "balance" of the frequency range sounds more linear, more appealing - I know technically it should sound the same but there's definitely a more "natural" and perhaps "weighty" output from it.
If you have re-flow capabilities I'd highly recommend this simple mod! Obviously the chip isn't being used to its full potential at this voltage but it's running at a nice level. Increasing the voltage means changing out a good few components on the board but I haven't really looked into that yet (and perhaps changing the sub output chip although that's just the same process).
I really like what I hear with the DDX320.
I got a wonderful sounding Xmos USB I2S device that I would really like to
use.
So the question if I2S could be feed to the DDX kept bugging me.
I tried connecting the Xmos to the STA320 while at the same time using a
different stream with the same sampling rate to the WM8805 but I got no
sound. To do that I removed the four resistors and used the pads to feed
the I2S signals including mckl from the Xmos chip. Maybe I gave up on it to
soon and it would work if I feed I2S while simultaneously feeding the
same signal as Spdif to the WM8805.
With virtual audio cable I could route the same stream from Foobar to my motherbord's
Toslink and to the Xmos I2S device simultaneously . That should theoretically cause the
WM8805 to send the right timing and sample rate information to the controller chip.
Does anybody know if this is worth another try or can I spare my time?
If the Xmos device wouldn't sound so good I could care less.
I also got two CM6631 devices and they are better than any USB to I2S
device I tried so far except for the Xmos but they are so buggy with both,
Windows7 and XP that I lost all my ambition modding them. One time you can
not go above 16 bit with Asio, another time you need to reinstall the driver
because Windows suddenly does not recognize the device anymore. Wasapi
sometimes out of the blue sends out a very high pitched sound and I need to
pause and start the song again. Very frustrating to say the least.
It's time for a Version 3 of the DDX-320 with I2S capability.
Klaus
I got a wonderful sounding Xmos USB I2S device that I would really like to
use.
So the question if I2S could be feed to the DDX kept bugging me.
I tried connecting the Xmos to the STA320 while at the same time using a
different stream with the same sampling rate to the WM8805 but I got no
sound. To do that I removed the four resistors and used the pads to feed
the I2S signals including mckl from the Xmos chip. Maybe I gave up on it to
soon and it would work if I feed I2S while simultaneously feeding the
same signal as Spdif to the WM8805.
With virtual audio cable I could route the same stream from Foobar to my motherbord's
Toslink and to the Xmos I2S device simultaneously . That should theoretically cause the
WM8805 to send the right timing and sample rate information to the controller chip.
Does anybody know if this is worth another try or can I spare my time?
If the Xmos device wouldn't sound so good I could care less.
I also got two CM6631 devices and they are better than any USB to I2S
device I tried so far except for the Xmos but they are so buggy with both,
Windows7 and XP that I lost all my ambition modding them. One time you can
not go above 16 bit with Asio, another time you need to reinstall the driver
because Windows suddenly does not recognize the device anymore. Wasapi
sometimes out of the blue sends out a very high pitched sound and I need to
pause and start the song again. Very frustrating to say the least.
It's time for a Version 3 of the DDX-320 with I2S capability.
Klaus
They initialize and control both chips (STA320 and WM8805) with the PIC.
Tapping I2S off won't work.
I made that proposal before to allow that I2S option.
They just refuse it, due to technical restrictions on the current setup.
In that context I asked for an option to be able to change the firmware of the PIC to get around that.
Many of the todays intelligent boards allow for firmware upgrades/updates.
I guess that won't happen soon if ever.
MiniDsp offers a 60$ "miniAMP" based on TI chip 5706. That one would accept I2S. Perhaps a nice alternative if you can live with a 20W ( effective range = 10W) amp
Cheers
Tapping I2S off won't work.
I made that proposal before to allow that I2S option.
They just refuse it, due to technical restrictions on the current setup.
In that context I asked for an option to be able to change the firmware of the PIC to get around that.
Many of the todays intelligent boards allow for firmware upgrades/updates.
I guess that won't happen soon if ever.
MiniDsp offers a 60$ "miniAMP" based on TI chip 5706. That one would accept I2S. Perhaps a nice alternative if you can live with a 20W ( effective range = 10W) amp
Cheers
I did seem to run into a major firmware issue.
I installed a spare DDX in the living room two weeks ago. I connected it to an old SB Duet I had at hand.
When using my Samsung remote on the TV, the DDX receives these codes and seems to process them. At one point it locks the amp/PIC up.
I only get it back working when removing the ribbon cable, power-up without that cable to accomplish some kind of reset, and then reconnect the ribbon cable. If you just power-down and power-up you won't get it back working.
That's pretty annoying, since you need that remote for setting the amp up
and do the volume control.
Therefore I can't turn IR fully off by removing or covering the IR-diode.
There is also no DIP switch to turn IR off.
Beside that I experience similar quality issues with that module as reported by somebody else earlier. E.g. One LED segment is much more dimmed than another one. If I recall it correctly the reason behind where poor workmanship -- poor soldering joints.
Beside that HifiMeDIY is not even responding to the first subject.
I issued a question 14 days ago in their forum.
If it continuous like that, it's the last product I bought from that company.
I installed a spare DDX in the living room two weeks ago. I connected it to an old SB Duet I had at hand.
When using my Samsung remote on the TV, the DDX receives these codes and seems to process them. At one point it locks the amp/PIC up.
I only get it back working when removing the ribbon cable, power-up without that cable to accomplish some kind of reset, and then reconnect the ribbon cable. If you just power-down and power-up you won't get it back working.
That's pretty annoying, since you need that remote for setting the amp up
and do the volume control.
Therefore I can't turn IR fully off by removing or covering the IR-diode.
There is also no DIP switch to turn IR off.
Beside that I experience similar quality issues with that module as reported by somebody else earlier. E.g. One LED segment is much more dimmed than another one. If I recall it correctly the reason behind where poor workmanship -- poor soldering joints.
Beside that HifiMeDIY is not even responding to the first subject.
I issued a question 14 days ago in their forum.
If it continuous like that, it's the last product I bought from that company.
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5 minutes after my "complaint" over here, I received an answer over at the vendor site forum.
It basically said that they can not cover all kind of remote codes.
That's right. I can understand that.
But at least they should allow valid codes only.
And I just figured. I said Samsung. Sorry it's a Sony. Still a major brand though.
It basically said that they can not cover all kind of remote codes.
That's right. I can understand that.
But at least they should allow valid codes only.
And I just figured. I said Samsung. Sorry it's a Sony. Still a major brand though.
Thanks Klaus,
So you think that parallel feeding the same signal to Spdif/Tos. input and I2S
to only the STA320 will not work? Theoretically the controler chip should
receive all necessary information from the WM8805 and set the STA320
parameters to lock on to the I2S signal that has the exact same sample
rate and clock speed.
Klaus
So you think that parallel feeding the same signal to Spdif/Tos. input and I2S
to only the STA320 will not work? Theoretically the controler chip should
receive all necessary information from the WM8805 and set the STA320
parameters to lock on to the I2S signal that has the exact same sample
rate and clock speed.
Klaus
damn!!!!!!!!!! I had problem display not working, not responding to remote and no sound. Now after reading Soundchecks post I restarted with riibon disconnected, took power off again and back on, connected ribbon cable again and display and remote is working again. Mystery seems solved, exept I did not have IR from other products in same room, for me it happened after listening a CD, took power off and after 15 minutes I moved DIP4 down (-10dB) power back on and no display/sound only leds working.
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