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Monkeyboi

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Monkeyboi last won the day on May 17 2014

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About Monkeyboi

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    D.I.Y. Audio Enthusiast

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  1. Very little in real terms with the HDMI interface hardware itself on most receivers. Some receivers might buffer and reclock the digital audio stream to significantly reduce jitter before sending it to the decoder DACs. An example is Sony's H.A.T.S. technique but only works with H.A.T.S. compatible sources. The DACs in the receiver and its associated electronics will determine the sound quality because in HDMI mode the DACs in the player are bypassed and play no role in the reproduced audio. The use of the multichannel analogue inputs on most receivers is another issue and there is no definitive answer on how this is handled unless the make and model is know and the relevant information is known. In this configuration the audio is decoded by the player and sent to the HT amplifier. Many modern amplifiers have a feature to adjust the time delay, speaker actual or imaged positions, frequency response (room correction) and levels. To achieve this the analogue signals are converted to digital to provide the manipulation of the audio by the DSP chip(s) then converted back to analogue via the DACs in the amplifier. So in essence multiple D-A and A-D conversions are involved thereby potentially degrading the original digital signals from the source disc. Therefore IMHO, the less conversions the better. In all my HT gear where digital signals are involved from the source I use the HDMI inputs out of preference. In two of the receivers I have, there are some HDMI inputs the manufacturer has labelled as "for high quality audio" even though these handle both video and audio. I will dig out the service manuals and examine the schematics to try to determine why these specific HDMI inputs are recommended for high quality audio over the other HDMI inputs. There's probably some difference, I just haven't bothered looking into it until now. Cheers, Alan R.
  2. It could be a faulty or out of spec component in the HF crossover. If you are handy with a soldering iron and have access to a LCR meter it will quickly identify the out of spec or defective part. Other issues could be a dry joint on the PCB. Cheers, Alan R.
  3. Yes, that is my experience and understanding too. I got slam dunked on a SACD import. Sent by the supplier through DHL When I came to pick up the package I was charged GST on both the cost of the SACDs and the shipping. Why they impose GST on freight is beyond me seeing that the majority of the freight cost would be provided by overseas providers, not here in Australia. Just another rip-off. The GST and duty on goods I can kind of understand, but freight or postage is just IMHO ridiculous. Do you get slapped a GST on a letter sent from overseas? 🙄 I'm not sure what the situation would be if the cables were declared as say "Returned from warranty repair". Would this still be subject to GST and import duties? I'm just trying to imagine a situation (albeit rare) where an item had to be sent off shore to be repaired under warranty as no service agent existed in Australia. I'm sure this might be the case with some hi-fi or camera gear. Would it be fair to stick the person claiming on a warranty with effectively double the GST and import duty? I think not, but I'm sure the guidelines probably don't have enough scope of interpretation or discretion in this one fits all world. Cheers, Alan R.
  4. I can tell you now, the training isn't delivered in any other language other than English, either as conventional instructor lead or as online learning units. The assessments are in English not that that means much these days and are online and done on their tablets or PCs. Also I can speak for one partner company doing NBN work under contract. The tablets and PCs given to the contractors don't have access the internet, only the intranet for security reasons and the devices are "locked down" to prevent the user from adding or deleting programs / apps from them, so yes to use translator apps they would have to take photos of the screen of their tablet or PC and use an app to do the translating. Not particularly efficient and some of the technical documents are hundreds of pages long. Do these apps also translate the diagrams and flowcharts. I'm guessing they do, and if so how accurately. Better than Google Translate one would hope. 🙄 Of course it doesn't prevent them from calling a colleague and asking for an interpretation and many do. And of course a lot of the work gets sub-sub contracted out so the poor bugger doing "the work" at the end of the line usually ends up getting $12.50 for a jumper running job at a pillar whilst the guy at the top gets $89.00 for the job he did nothing for except pass down the line. Welcome to the world of sub contracting at its worst. So when you do the math, the bottom of the line guy is battling to make ends meet. When you factor in all the "joys" of subcontracting, the subbie has to provide his own vehicle, tools, test instruments, safety gear, insurances, pay his own superannuation, vehicle running costs, mobile phone etc. The average jumpering job takes about 30 minutes of on-site time if done properly and assuming no delays with NBN activations. The contractors don't get any payment for travelling from job to job. Tell me how this works out as a viable business at $12.50 / hour? Because if you factor in say 30 minutes travelling time between jobs the guy is effectively working for $12.50 / hour before expenses. Even for the prime contractor getting $89.00 per ticket of work and assuming he is actually doing the work there isn't much gravy left in the pie. Not when you can't be guaranteed a full day of work each day, every day. Anyone who does contract work in the telecommunications industry will know what I mean. I've probably "Wiki-leaked" way too much in this post. Cheers, Alan R.
  5. The NBN tech is supposed to be using the existing copper pair / coaxial cable into your premises from the street / pole as this is what provided your pre-NBN service on (presumably ADSL or HFC). Other than a fault, there is no valid reason to change over to a different pair. However IME the problem lays with incorrect cable records and / or the incompetence of the tech. Let's take the FTTN example which uses your existing copper cable connection, and just for the purpose of explanation we assume that upto the point of changeover to carriage by the NBN you had a working ADSL / PSTN service. In FTTN all that is required to be done by the NBN tech is to disconnect a couple of 2 wire jumpers (point to point wiring connections) in a roadside pillar and run 1 new jumper. The tech then checks for DSL sync to confirm the service is leaving the pillar on the correct pair which then makes its way to your premises exactly the same way it did before been cut over to NBN carriage. Usually prior to this activity your service provider should have sent a (non-NBN) tech to your premises to install an NBN FTTN compatible gateway (modem). Some ISP offer a DIY self install kit. It's not complicated and many of my non-technical friends have been able to successfully perform the pre-installation as it (mostly) does not involve tinkering with the existing cabling in the premises in a simple straight forward wiring setup. For HFC it's slightly different depending on what other services are carried on the same coaxial cable (e.g. Foxtel) but for a successful cut-over to NBN carriage does not require a tech to do any work on the street cable, rather more to install or configure a splitter in the premises to allow the co-existence of other services such as Foxtel on HFC. So why are so many people having such a large number of problems when it comes to transitioning from whatever technology they are currently on to carriage via the NBN? As I alluded to at the start of this reply. Incorrect cable records and / or technical incompetence. Sadly I have had some of these NBN contractors in my classes. Straight off the plane with questionable qualifications (IOW not worth the paper they are printed on) from countries where you can buy your degree or qualification without a single day of attendance at the college or uni. 100% are contractors with a 457 visa (or equivalent) and an ABN. Some are locals with equally unimpressive qualifications or experience. Just to put things into perspective. I had a contractor from a foreign country in one of my classes. He could barely read English. So I ask you..... if he can't read English how the hell is he going to read the Work Order and secondly how is he going to read the technical work instructions he needs to refer to in order to do the work correctly? I rest my case gentlemen and ladies. 😔 Cheers, Alan R.
  6. Get an old Sony Blu-ray player like a BDP-S390 or BDP-S5100 . There are a number of compatible models and makes that will work. Be aware that you can't rip SACDs on all Blu-ray players, just some models. I have both the models mentioned above and they work just fine for ripping and can be found on Fleabay or Facebook Marketplace for bugger all cost. You will need a small capacity USB memory stick to store some code on and a network connection between the player to your PC. Can be ethernet or wi-fi but ethernet is recommended. You will need to download a program for your PC and the code that goes on the USB stick that plugs into the USB port of the Blu-ray player. The program can rip SACDs to .dsf, .dff, .iso etc and supports both stereo and multichannel. It can also add tagging if required as part of the ripping process. Works well for me. I've successfully ripped hundreds of SACDs in my collection so I can stream them from my NAS. You don't need a powerful PC or Mac to perform the ripping. I'm using an old Dell Vostro 420 running Win 10. PM me for the details as AFAIK it isn't considered to be good kudos to link to other forums here or post details of how to copy music as some see it as an infringement on copyright even though you're ripping the discs you own and already paid for. Cheers, Alan R.
  7. Absolutely. If something fails you can't just "pull over" on cloud #17 for a quick pitstop to change a card or a component. Substandard, out of spec or fake parts just aren't worth the potential grief they can cause you. That's why verifying the lineage of components that will be used in critical applications is so important. Cheers, Alan R.
  8. Today I thought I'd look into the typical selling prices for the OPA2134PA (8 pin DIL package) and I found some interesting results. Mouser $7.18 ea Texas Instruments Digi-key $7.17 ea Texas Instruments RS $7.04 ea Texas Instruments Jaycar $8.95 ea brand not stated Ebay $0.98 ea in quantities of 5. Price is inclusive of GST and delivery. Burr-Brown suspected fakes (see photo) The genuine BB chips have a notch cut into the end of the IC between pins 1 and 8 (see photo). There is a distinctive indentation indicating pin 1 which is closely aligned with the pin. The fake BB chips have no end notch and the pin 1 indicator is much larger and slightly offset from the pin. (see photo of the fake chips). I have included a photo of a assumed genuine Ti TL082CP which retails for about the $2.00 mark from major component retailers. Note similarity of the package to the fake BB OPA2134AP. 🙄 So to me it comes as no surprise that some allegedly dishonest vendors might be rebadging much cheaper TL082 as an OPA2134. 😡 Cheers, Alan R.
  9. Although rare it is sadly a fact of life that fake parts are a reality in the electronics industry. Even large reputable (and not cheap) suppliers like RS, Digikey, Mouser, Element 14 and the suchlike aren't completely immune to occasionally sourcing components from questionable distributors. Certainly some brands of components are more likely to be "copied" than others simply based on the genuine part's reputation, specifications, cost and availability. So when I see normally expensive brands offered on Fleabay for ridiculously low prices the "don't go there" alarm gets triggered and I don't waste my time or my money purchasing what may very well turn out to be cheap and nasty rubbish. Years ago and probably is still the case, fake discrete semiconductor devices flooded the market mainly from Chinese suppliers using Fleabay as the means of retailing. As an example it wasn't uncommon for the humble 2N3055 power transistor in the metal TO-3 case to be faked. More than often they would fail well before reaching their maximum operating parameters. After having personally experienced a number of successive failures from a batch of devices from the same supplier I got out the junior hacksaw and cut off the top of one of the suspect devices only to discover to my horror that the die inside the case was a mere fraction of the size of the genuine 2N3055. Needless to say it was no surprise that the fake 2N3055s failed well below the collector current and power dissipation of the genuine article. So when I read that there are fake op-amps that either fail unexpectedly or have poor noise performance it comes as no surprise. One way to spot fakes is to examine the part ID or logo and compare it with a known genuine part. Quite often the markings are blurred, wrong font, wrong size or are faint on the fake part. Another dead giveaway is with some fake parts the number can be easily rubbed off using a cotton bud dipped in isopropyl alcohol. So when it comes to prototyping, production or repair of a product I always try to verify the lineage of my parts. Why? Because a substandard part can end up costing you $$$$ and time, not to mention frustration and reputation. Nothing worse than repairing something only to have it returned a short while later with the same problem or worse. In the case of the suspect fake OPA2134 op-amps one could spend hours chasing up a noise fault suspecting other circuit components, power supply noise or even circuit topology as the cause, only to be chasing a red herring instead. I am a member of a number of electronics groups on Facebook. In one group there is unfortunately a mindset amongst some of the members there that using substandard or fake parts is an acceptable practice citing that the group is all about "cheap" electronics. IMHO that creates a mindset in some of the younger (and even older novice) members that using substandard parts or parts not fit for purpose is okay as long as it appears to work on power up and the magic smoke doesn't escape in the first few weeks of operation totally ignoring safety or the consequential damage that might occur when the fake or substandard part fails. Apologies for the long post, but people profiting from vending fake parts for a huge profit really makes me angry. We buy components in good faith that what we will be receiving is the genuine article and expect those parts to perform to the manufacturer's published specification. In the case of the noisy OPA2134 op-amps I would contact the manufacturer and offer to send the IC(s) back to them for quality control evaluation. More than often they generally send you a bunch of replacements for free. Cheers, Alan R.
  10. Gee other first world countries don't seem to be suffering from the same problems to nearly the same extent. It's not as if we didn't have streaming services before the NBN. I recall iiNet having Fetch TV long before Netflix and Stan commenced streaming on the internet. Back in the day Fetch TV and Foxtel over ADSL was streamed into the majority of homes in Australia via ADSL so IMHO the precedent for streaming services was already in place before the NBN has a single end user online. As for NBN Fixed Wireless services. I'm on a 25/5 plan which is the fastest service my provider can offer me in my area. I and many of my neighbours subscribe to VoD services such as Netflix or Stan. Living in a rural area it's about the only way we can get entertainment other than FTA TV as the nearest video library is some 15km away which carries bugger all titles anyway. Just as well it appears to be working just fine (at the moment) in my area. NBN Fixed Wireless still remains at about 5% of the end user base. This is what the original concept envisaged and that hasn't changed. However since its initial conception the NBN has undergone a metamorphosis when the Coalition introduced FTTN which it later reluctantly admitted was a poor choice of technology when either they should have pursued FTTP or the more practical lower cost option of FTTC. Cheers, Alan R.
  11. They should fix it like they used to in the good ol' days before there was any talk about the NBN. Admittedly I don't blame Telstra for not doing much remedial work on their network prior to the sell off of the Customer Access Network (aka the street cable) to NBN at a bagain basement price. If you look into it further, NBN own the cables that carry the services but AFAIA Telstra still owns the pits, manholes and ducts (conduits) that are located on public land (IOW in the streets and crown land). Therefore one might assume that if a duct is blocked due to (say collapse of the conduit) that the owner of said duct would be responsible for removing the blockage so as to allow a new or replacement cable(s) to be hauled through???? There are probably (no actually) a lack of skills and knowledge in some if not most of the workforce maintaining this network of cables and ducts. With the Big T shedding some 20,000 workers in recent times one might hope that some of the skilled workers actually have the funds to set up their own small businesses and contract back to Telstra and or the NBN to perform remedial works but I suspect most won't as the partner companies have already got a cheap subcontracted workforce from overseas. Most of which will work for peanuts and despite been qualified as a communications engineer in their own country simply don't have a clue when it comes to the cable network here. One only has to lift the cover on a street pillar to see that the standard of workmanship is extremely poor. It's as if they have no idea what they are doing. Poorly trained, not audited, inexperienced, poorly equipped and no training on how to test services and interpret the results. Sorry but IMHO you can't just take an unskilled and inexperienced person and let them loose on a telecommunications network and not expect quite a few monumental stuff ups. Do I sound pessimistic? I sure do, and why? As they say "What is the difference between a pessimist and an optimist?" The pessimist has more information. BTW, running a slave or temporary cable to keep services working is only a short term solution according to NBN policy. There are reasons for this. One is a potential safety hazard to the public and secondly as said before it's only supposed to be a temporary solution until remedial works can be undertaken. However IME NBN contractors sometimes run a slave cable simply because they either don't know how to locate the fault affecting the service and repair it, or there is more money to be gained by running the slave cable. All goes back to skills (or lack thereof) and the fact that NBN doesn't always audit work to verify if the fault can be remedied by means other than running a slave cable on the ground, over fence posts and strung between trees. Cheers, Alan R.
  12. So is eating, affordable housing (if you are renting) and most importantly for the average Joe an income. Not all jobs are in the cities. If Australians just chose to no longer live and work in rural areas who would be growing our food and providing all the services that go with it? Sorry, but IMHO the NBN isn't the be all and end all of living. Yes, we would like a better, more reliable internet / phone service and at an affordable price. Now there is talk that the NBN is proposing a levy on data for streaming services like Netflix, Stan et al. I feel sorry for those Australian taxpayers who are contributing to the building and maintenance of the NBN but don't yet have it. Cheers, Alan R.
  13. Steve, this unfortunately is the level of service consumers get when you outsource everything. The big T hasn't done itself any favours despite their new T22 strategy which is apparently supposed to be all about the new digital connectivity age and customer service. 🙄 Hopefully you will have more ongoing joy with Optus. My recent experience with iiNet hasn't been the best either. Firstly it looks like support has now been outsourced to the Philippines. They screwed up the first ticket of work, then a call to their Cape Town operations centre got a bit of progress but still significant issues. Now finally after 19 days they have got the email working again and restored our website. In the interim it's cost the business thousands of dollars in lost revenue and generated a whole pile of angry clients who have not been getting any response to emails for almost three weeks. Some thought they might have some success by attempting to contact us through our website portal, but alas iiNet not only trashed all our domain email boxes but our domain and website as well. 😡 One client called me on my mobile to ask me if we had gone out of business. That's when I discovered our website had disappeared. How did all this happen? Well apparently there was some sort of stuff up with the domain hosting mob (which I understand are part of iiNet as iiNet take the money from us). They "accidentally" cancelled our domain thereby "breaking" all the links to it. Fortunately only the hosting part is with iiNet and the registration is with MelbourneIT otherwise if someone wanted our domain name we'd really have been up the creek without a paddle. So service for which you pay up front for isn't what it used to be. Welcome to the brave new world of communications. Cheers, Alan R.
  14. Yes, if you aren't already using them, try the NE5534AN. These have a better noise spec than the NE5534. Built many phono and line preamps using the NE5534AN. Cheers, Alan R.
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