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I have a no lock phenomen in auto mode with my Squeezebox devices, manual works just fine (without audible problems). In auto mode it detects the signal for a fragment of a second, then skips the input, rotates over teh other inputs, detects for a split second etc...Quote:
Have other BM owners had issues with the DAC not locking onto signals coming into the coaxial inputs or perhaps not working correctly on any input?
See my post #1197, Dave. It only happened with my Sky HD box and Stan has sent me revised firmware that fixed it.
The BM has been back to Stan and he has installed the new firmware Martin, the issue is still there however. I am beginning to think there is a specific fault with this particular unit as I had to reset it again today. I can't rely on it to work from switch on or when changing inputs, without having to turn it off and back on again :scratch:
Ah ok, sounds like it might be a faulty one.
It's the code hack that was done to bypass the auto function. It was done in haste to satisfy a particular request, but it seems to have a function call hidden somewhere inside the C code that is misbehaving.
The later firmware has a signal lock correction for things like the SB and Airport Express. It's the buffering delay in the SB when it temporarily stops decoding the audio whilst grabbing more audio data from the server supplying it with music. That buffering delay from the SB can be long enough for the BM to think that the SB has stopped operating, in which case the auto search will shoot off to look for a new valid audio source. email me so I can cross check if you have the SB update in the firmware or not.Quote:
Originally Posted by nightyy
I have enough requests for this to justify a proper code rewrite instead of a quick hack. Anyone who needs this feature for important operational reason should email me. I can then put your email in a notification list. Don't PM me if you would like to be on the list or if you have any important technical questions.Quote:
Originally Posted by nightyy
I posted a picture of the alpha version of the BM with USB in a thread. I am making some changes and improvements based on suggestions and observations by a Danish and an Italian beta tester.Quote:
Originally Posted by tadatin
Just a quick update on the USB version of the Bushmaster.
Due to a recent set of agreements with a couple of component manufacturers I have managed to get hold of some additional information on certain components. One set of that data will allow me to do some exciting things, like the ability to take an adaptive or isynchronous data stream from TOSLINK, coax or USB, and buffer it, before using an asynchronous process to sort out jitter. What that means is that in the case of the USB connection method no proprietary drivers are required to be installed on your computer in order to obtain an asynchronous data delivery at the input of the DAC chip. That also means that the TOSLINK and coax data stream will be treated in an asynchronous way once they enter the DAC.
I am not sure about how it all works, but I have been testing it on a modified BM at 24/192KHz with a TOSLINK lead that is less than 3mm thick. I'll have to look for a volunteer or two to double check my results since I am a bit cautious with this asynch malarkey.
The other one is no less exciting. It is not uncommon to see DAC specs mentioning upsampling to 192KHz. I have had a play with a couple but found the audio of an upsampled 44.1Kz file to 192KHz to sound softer. In some cases the tense fast paced action had been converted to a dragged out drama so to speak. This alternative DAC chip approaches the data quite differently however. It processes that data in its original sample rate, but in a 24 bit domain.
So what's different with that compared to upsampling you ask. Well upsampling to 192KHz requires additional padding bits to make up the longer byte. I reckon that it is these extra bits that can make the audio sound softer. But processing in the 24 bit domain is quite often used in the recording and mastering process, after which an audio file can be converted to a 16 bit/44.1KHz CD track for instance by removing 8 bits somehow. Don't ask me how they do it. I have absolutely no idea. The new data I now have in my possession is quite vague in how the process works as far as processing any audio file between 12 to 24 bits in the 24 bits domain is concerned, but I am busy designing a test platform that can only go up to 16 bits, and another platform that uses the 24 bit processing method. That should give me a chance to hear if there are any positive and/or negative effects from using the 24 bit process when a 16 bit audio file is played back. I don't expect any difference with a regular 24 bit audio file, but I shall test that as well just in case.
So what has this got to do with the USB DAC? Well I can't afford to invest in the production of a USB DAC now, whilst sitting on such important information. I feel that since I am still in the preproduction stage of the USB DAC I can take a gamble and take a financial hit on the costs of the R&D of the current USB DAC development, and switch to building a new DAC with the new technical specs. I try to innovate instead of copy. If I wait till I design a next DAC range after the existing or planned one, my competitors might already be using the latest process. But scrapping the existing USB production plan and starting all over again will mean additional delays. It could be an expensive gamble, with no certainty of commercial success afterwards. So any input from other AoS members would be very helpful.
I would love to volunteer BUT need the variable output :(
I am waiting for some special 3 core wire that I used for modding to the variable output. If it arrives in the post this morning then maybe I can sort things out with you.Quote:
Originally Posted by Covenant
You'll need to do a before and after test to confirm the results. I shall PM you about how to go about that.
That's great Stan, many thanks
The asynchronous TOSLINK/Coax sounds interesting if it can reduce jitter but I currently have no need for USB.
24 bit/192 khz capability would be good as I have been reading quite a bit lately regarding output of Computer based systems ie Macbook pro and toslink is not best output, USB/spdif allows output of 24 bit/192khz into DAC,s capable of processing this.
When outputting 24 bit/192 khz downloads however from HD tracks and the like USB/spdif asynchronous transfer has been delivering superb results. Even CD 16 bit recordings via USB sound a lot better than toslink with reduction in jitter much better.
I also don't need USB input on the DAC as I do room correction in the digital domain between my hiFace EVO and Bushmaster but I'd be interested in trying any potential improvements to the coax/toslink inputs on the Bushmaster. I'd also be very interested in trying a Beresford async USB to coax/toslink transport if should a thing ever got produced. Hint hint. :eyebrows:
If it were me I would take a hit on the current version and move to the new one - I can only see demand for USB dacs growing in the short term but its a competitive and fast moving market and in my opinion new technology sells.Quote:
Originally Posted by StanleyB
I would love to try a Beresford USB dac - right now - but the lack of USB didn't stop me buying a Bushmaster - if the USB version is delayed I might keep my variable out bushmaster and close my for sale thread. I was sort of hoping but if there is something better on the horizon I would rather wait or bag an alpha model short term
What I am looking to do is to add to the range. The BM can produce even better results with a few mods. )That reminds me to start a new thread on some mods as requested by a many people.) It can also already process in asynch mode based on the test FW that I have been trying out. More about that another time. I refer to it as the firmware, but in reality it is the whole operating system run by a MCU. At the moment I am running it at 20MHz, but I am looking to see if it is possible to upgrade it to a higher speed with a more powerful central core.
As for the additions to the range: it has more parts and would have to be wider than the BM in order fit in all the extra bits. I am considering using the new info to make two DACs. One would be just optical and coax inputs, whilst the other would have a USB socket as well. The plan is to keep the retail price (excluding VAT etc.) below £250, without compromising the performance.
Sounds reasonable. As a happy user of a HiFace Evo USB/SPDIF converter (except its incompatibility with my SOtM PCIe USB card), I would be very happy to see a good value Beresford DAC with a USB interface of equivalent performance built-in, thereby saving another box and associated PSU. The DAC market is getting pretty crowded, so I don't think there's much point in producing a USB DAC at the proposed price unless it is a real "giant killer", for which you have more than a bit of form. I do feel that a USB DAC will not be taken seriously in the wider marketplace unless it has an asynchronous USB interface, and support for sampling frequencies in excess of 96kHz. I know that the latter criterion is marketing BS, but that's what people expect to see in the specs.
Quote:
Originally Posted by StanleyB
I am all for async mode in the BM to improve sound quality and that is much more important to me than a USB interface, for which I have no use in my system. Since most material I play is either 16/44 or 16/48, it's these formats and the improvement thereof that matter more than playback of the paltry selection of hi-res files available.
I have started fitting the asynch code in some DACs for people to try out and report back. What I did notice whilst testing it is that the biggest improvements are with my playback from the PC. My Touch doesn't show any difference with or without it. But I know a few people who have problems with the Toucj and the BM at high bitrates. I'll dig up a few emails and see if they still got their BM and are willing to be guinea pigs.
My interest is particularly aimed at 192KHz playback with Toslink. The asynch code "seems" to produce a near identical performance compared to coax at 192KHz. Many say that optical is patchy above 96KHz. So I reckon that is a good starting point to test the validity and robustness of the system. I wished that I could get the code to run at a higher speed than 20MHz though. It's something I have to look into. Luckily the MCU is in a socket. So an adapter board with a faster chip and oscillator would be a nice little mod.
By the way Brutus get in touch. I got a few updates to the Venom mod :eyebrows:. Just return postage and the cost of a beer required in your case if you want to give the mods a go.
The arguments for playback above 2/96KHz seem dubious, many comments from people suggest that the recording quality is responsible for any perceived improvement. What is your own view Stan?
My own view in the case of the Touch is that I think the issue is related to the year it was built. I know someone who has two pieces of the Touch, with both of them running the same firmware bulld. But one plays OK on everything, whilst the other is a bit patchy. The two units were each bought in different years.
Mine is a relatively late Touch and I have no trouble playing 24/192 via Toslink or co-ax. I use the EDO software mod.
96Khz is already past the upper rated bandwidth limit of the vast majority of Toslink cables at 12.3MHz. At 192KHz you are double that, refraction and internal reflections will limit the distance and quality of the signal at such speeds and given the use of slow rise time diodes with Toslink I'd be surprised that 192Khz is genuinely achievable, certainly not without severe signal degradation. Also the Tx and Rx modules need to be rated for this speed, many struggle to get to 6Mhz although the better Toshiba Rx and Tx modules are rated to 15Mhz....still some way off 25Mhz.
Agreed, Neal. That's the reason I believe that the Touch/BM sounds better via co-ax and I'm leaving it that way. In any case, both of my optical inputs are taken up with Sky HD and Blu-ray.
Can I offer my own view even though my name is not Stan?Quote:
Originally Posted by Covenant
I am one of those people who claim they can hear improvements in sound quality with the so-call hi-rez format. Of course, I'm talking listening comparatively to the same master, rendered in standard red book 16 bit/44.1 kHz and also in 24 bit/96 kHz (otherwise we'd be comparing apples to oranges). My experience when comparing the two formats is that hi rez offers more 'depth', it appears less strenuous to my ears.
That said, I've been humbled recently when reviewing some hi rez formats with a friend. We did a bit of blindfold listening, and I had to throw the towel in and admit that under blindfold conditions, all the perceived 'depth' and 'effortlessness' of the hi rez format over the regular format somehow melted away and disappeared. I wasn't able to differentiate between the two.
So at this point I don't know what to think about the format wars...
If we take into account that it's even physically possible for the ear and mind to hear the difference I think we vastly underestimate the psychologie that's behind it.
We are social beings that get's influenced everyday , in the end I'm glad I can still enjoy good low rez music :) .
I recommend having a play around with the free sample files from www.2l.no where the same recordings are available in various formats. 192kHz does not bring anything useful to the musical party, IME, but I do find 24bit 96kHz to be best. That said, I have recordings in that format which are bettered by plain CD versions of the same performances, so even though something has been overhauled and flogged by the record companies as genuine high-res (and most are), that does not guarantee that the remastering has not ruined the sound. There are many variables here, but the one certainty is that we don't need bit depths greater than 24bit, nor sampling frequencies above 96kHz.
I agree, Hugo, I haven't heard any 24/192 files that sound better than 24/96. It could be that the stresses of a higher bitrate and rounder waveforms counter any possible benefit it might have over 96kHz sample rate.
I got my Bushmaster today
It is very tragic news that Stan has had today
I will say that the DAC seems super smooth, that's my first impression of it, sort of analogue sounding
I'm quite sure that I need a better Toslink cable as the one I'm using is a pretty cheap old thing
Can anyone recommend a reasonably priced Toslink cable to use?
Thanks all
I use Mark Grant glass core cables and find they do a great job. Stan also sells THIS cable which looks very similar to the Mark Grant cables.
They're both very high quality multi-fibre cables that are vastly superior to the single core plastic crap that most commercial Toslink cables are made of.
I really don't like the very bright blue LED light
I've tried to turn it off as per instructions but I guess that facility has been removed, that's a real shame :(
Uh oh... That will be seven Hail Mary's you'll need to say tonight then Bev :lol:
All jokes aside, either plop a heavy duty sticker over it or a piece of electrical tape, or perhaps ask Stan if it is safe to go inside and snip it out of circuit.
I have the same issue with my router - it's a bit Heath Robinson, but a judiciously applied blob of BluTack works wonders.Quote:
Originally Posted by Ninanina
Black PVC tape for me.
There is somewhere that sells sheets of stickers for led / display blanking, I cant remember what they are called though ?
Found it :doh:, light dims
http://www.lightdims.com/
Simple ideas are always the best.
That's a great little idea
I've ordered the ones that dim the LED rather than block it 100%
Only cost £1.33 delivered, bargain!
:)
I'm trying to buy one of these but the website doesn't work?
Anyone help, are these for sale or has something happened?
Thanks
Tony
http://www.homehifi.co.uk/PP/Product_ordering.html
You could phone Stanley if website not working (during working hours), details here:
http://www.beresford.me/others/contact.html
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Thnaks Mark, I'll do that tomorrow:cool:Quote:
Originally Posted by Mark Grant
I don`t know if you consider this reasonably priced, but they are very good http://www.lifatec.com/toslink2.htmlQuote:
Originally Posted by Ninanina
As mentioned by me a couple of weeks ago, the owner of the workshop that makes the enclosure for the Bushmaster passed away on the 2nd of May. This has had a knock on effect for all his customers waiting for their standing orders. A new guy is taking over the business, but he will take some time to get up to speed and clear the backlog.Quote:
Originally Posted by twotone
I am using the time to make some layout changes and reduce the depth of the case. I have no idea as yet if this will have an impact on the sound, but if it does I hope it is a positive one. I'll have the new blank PCB maybe next week. I can then populate the PCB with components and try it out to see if it sounds the same, worse, or better. If it is the same or better I'll go with the reduced case depth when it is my turn for the case production.
I'll probably have to call it the MK2 version so that there is no confusion with the two types of boards and cases.
As for the date when I next have stock: I would think that July is a reasonable bet. But I should know by the week after next if the amended PCB size sounds better, worse or the same as the existing PCB.
My apologies to everyone who is looking forward to try out the Bushmaster. If you are prepared to hang on till production is up and running again and you are an AoS member I am prepared to offer a "waiting time discount" to those who wish to be placed on the waiting list. PM me your email address if you want to be on the list. No direct emails please! Only PMs will be accepted as a valid form of evidence of AoS membership.
That's a very generous offer, Stan. Thank you on behalf of the AoS membership and I hope you get your production back up to speed soon.
Thanks for the up-date Stan and sorry for the difficulties you are currently experiencing.Quote:
Originally Posted by StanleyB
Condolences to the family.
PM sent.
Hi there everyone.
Can't wait to get my hand on one of these dacs. I had a good conversation last week with stan and thereafter asked for one of these dacs to be made for me. I thought I might as well join the forums, especially as I've read this thread nearly in it's entirety - captivating stuff!
I also want to express my sympathy for the family/friends of the workshop owner and understand how this would affect the manufacture of these dacs.
I have been trying some next generation fibre optic communication spec TOSLINK sockets in the BM MK2 that are officially approved for use at up to 25MHz. The cost is several times the price I am paying for the sockets that I have been using, but the sonic results so far are well worth the additional cost. They are a lot more analogue sounding than the current sockets in a straight forward side by side test of the two types of sockets fitted to the same test platform. The only major consideration was that these TOSLINK sockets needed their own dedicated low noise power supply feed in order to achieve the 25MHz performance.Quote:
Originally Posted by NRG
Sounds promising, Stan. Since the Sky HD boxes have optical only output, I am very interested in anything that improves the already stonkingly good SQ. Even for low bandwidths, those improved sockets (with a decent cable) should square up the waveform and help to reduce jitter.
A pity I don't yet have an enclosure to fit the BM2 in. Otherwise I could have loaned you the alpha PCB to try out for yourself and carry out some very interesting tests.
As and when, Stan. There is only one you, unfortunately :)
Interesting Stan. Are they from Toshiba? What about the cable itself?Quote:
Originally Posted by StanleyB