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jamesmking

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Everything posted by jamesmking

  1. Thank you Kerry, however, yesterday I then tried an uncoated 2 flute 2mm slotting endmill... the results was not good at all.... very poor chip evacuation and lots of chips welding to each other. Almost no chips get thrown clear of the cut. I'm not sure if the end mill is garbage or if something else is wrong.... I was looking online for some kind of guide that had photos of poor results and what to do about them... but there seems to be very little information other than feeds and speed calculators which seem to suggest parameters that I cant get close to. I tried to extrapolate settings from the great results I got from the single flute 2mm end mill to a single flute 3.175mm end mill but to no avail. The 3.175 end mill could not run at anywhere near the rpm or depth of cut of the 2mm end mill without welding, vibration and large burns on the edges of the cut.... Perhaps the 3.175mm end mill is just crap (its not the same brand as the 2mm)... wow cnc aluminium is frustrating...
  2. I'm starting to get the feeds and speeds dialled in now I have a 1.5Kw water-cooled spindle and some good spoil board bed rigidity, properly levelled and trammed the machine. I'm slowly gaining confidence and beginning to believe the reviews that said the Vasto can cut aluminium... I managed to cut ventilation slots in aluminium using a 2mm diameter single flute DLC end mill with 300mm/min feed rate, depth of cut 1.6mm, 50% overlap, 18000rpm. The test slots were 160mm long, 3mm deep, I tried 2mm, 3mm and 4mm widths.... surface finish is like a mirror, no burs and no chips welding themselves to anything. No cutting fluid was used and there was no finishing pass: Thats so better than my first attempts with the 400W motor and a corn cob end mill which produced garbage surface finish at much lower surface speeds, much lower depth of cut and destroyed the end mill very quickly:
  3. I entirely agree, for me the object of listening to music is emotional involvement and enjoyment. The combination of the mostly modern T2 and the SR007 does this for me in a way nothing else I have listened to can. It makes music rather than throwing detail and frequencies at you. I don't care if its not as "accurate" as something else or technically or measurably not as good. I know of no measurement or technical specification that correlates with enjoyment or musicality. I think the general trend in hifi has been for things to get brighter and brighter in the search for more "resolution" and "speed" and more "high end" sound, hence the trends for metal drivers, more silver plated/solid silver things like wires/fuses caps etc etc. If you like brighter then the sr007 is not for you, if you don't like modern sound then the sr007 can be wonderful - if driven properly and the standard stax energizers can't drive it property at all.
  4. my solution to have solid brick between me and the laser. I run the laser in one room with the room door closed and control/monitor it from the adjoining room using a cheap web camera. I don't put any faith in it or the goggles that came with the laser....
  5. the diode lasers tend to come in rectangular aluminium blocks which have fins and act as heatsinks with a fan blowing downwards through the heatsink and a small controller on the top. The standard 400W spindle mount on my machine has 4 small notches in it so it can also mount the laser just by holding on to the corners. You don't need a high clamping force. So you could probably 3d print something if necessary. The hole is 52mm diameter. If you are planning to engrave or cut wood then additional air flow is recommended to clear the smoke (which would otherwise scatter the laser light) for aluminium engraving there seems to be no smoke. wow that spindle with quick change costs more than my entire cnc machine with the upgrades I have done so far.... My vfd and spindle is cheap chinesium, the only issues going that route is that there is a general lack of documentation and the seller could not help so i had to guess, experiment and look at you tube videos of similar setups for the vfd settings etc to get things to work. The vfd did come with a manual which was mostly understandable but although I purchased the spindle and vfd as a bundle the spindle had zero documentation and no information on how to set it up the vfd for it... the seller could not even tell me the diameter of the tubing required to fit the compression fittings on the spindle for the water cooling... so I had to guess and fortunately got it right first time. I also had to guess how many poles the motor had and use a tachometer to verify.... So if you are going chinesium I would ask the seller some questions about the tube diameters, motor poles, vfd settings etc and see if they have a clue before purchasing from them... Also I have found a general lack of attention to detail going chinesium, for example the vfd has three terminals marked earth. Two are totally isolated from everything including each other. Only one actually connects to the earth pin of the mains plug and the spindle takes a 4 pin plug, 3 for the power phases and you would assume the 4th pin is to ground the spindle body, nope no continuity to the body. Also on the vfd it has a temperature readout for the driver mostfets... always says 0C googling says this is normal temp never implemented....
  6. i have the foxalien 20W which is a single diode with 5W actual optical output. https://www.foxalien.com/en-gb/collections/cnc-accessories/products/foxalien-20w-fixed-focus-blue-laser-module-kit fox alien also sell a 40W which is dual diode and about 10W optical output. You need a cnc controller which has a laser output. The fox alien is 3 pin - 0V dc power ( I think 12 or 24V) and a pwm for laser power control. Im using lightburn software which works well and has some laser test and calibration templates built in. General consensus on the internet seems to be that if you run a diode laser at full output you wear out the diode very quickly. So im tending to go slower movement and lowish power. The cnc controller board takes the spindle speed control commands and converts them to pwm signals for the laser output power control. On the fox alien vasto this requires setting a slide switch on the back of the controller to laser mode AND sending a G code command to go into laser mode. The slide switch disables the 48VDC motor output via a relay, disables rpm control via the speed potentiometer and enables the 3 pin laser output. The g code command tells the cnc controller to convert g code rpm commands to a pwm laser power control signal. I have also changed the stock 400W 48VDC air cooled spindle for a 65mm diameter er11 1.5Kw water cooled and a vfd. I would have preferred 80mm diameter er16 as suggested in this thread but I don't have an 80mm mounting bracket and the Z axis of my cnc does not look like it will take a bracket for 80mm spindles. Initial results are promising compared to the 400W. I still need to tweak the vfd settings for accel, breaking and torque. The stock spindle is cheap and nasty. I took it apart and it has two small bearings and the case is thin and the entire thing is held together with two long bolts. Its not very rigid at all and certainly seems to be one of the weaknesses of the machine along with the spoil board.. The 1.5Kw feels far more rigid and is 3 phase 220VAC.
  7. normally if you go from 120V to 240V you half the current draw power = current * voltage so you may have a problem. Assuming the amp did not blow fuses when set to 120V the same value fuse should not blow at 240V... fuses can weaken over time and they do vary considerably. EEV blog on you tube did some interesting experiments and found the fuses ratings to be at best a guestimate. With large variations in the fail current for fuses from the same batch. There are multiple versions of the DIY T2 and the choice of valves effects power consumption a little. My T2 consumes about 205W once warmed up (mostly modern T2 with tung-sol el34 and genalex 6922, kghssv psu). there is a high voltage delay built in to allow the tubes some warm up before applying high voltages. When the high voltage psu switches on it initially has to fill the filter caps and this makes short duration current surge of more than 4A. Assuming there is no short circuit in your high voltage rails and you have not wired up your transformer incorrectly, its this initial charge that's blown your fuse. I am currently running 5A slow and that been fine for many months. 4A slow blow might be ok too. Having said that I always specify my transformers with resettable thermal fuses built in for a bit of extra protection.
  8. The 12900k is very good at single threaded performance, multi threaded is good BUT its value for money is poor and the motherboards are not cheap.... yes you get newer versions of pcie but apart from a few expensive M.2 ssds nothing really takes advantage of the new pcie. the 12xxx series have performance cores and non performance cores and it makes the operating systems task scheduler much more complex because it now has to decide which tasks should go on the high performance cores vs which go on the lower performance cores.... and the new scheduler is only available in windows 11, so if you stick with 10 you potentially can lose some performance 12xxx series support both ddr5 ram and ddr4 but not at the same time (so your choice or ram and motherboard are tied together) ddr5 ram is almost twice the price of ddr4 for perhaps a 10% performance up lift... also most 12xxx motherboards don't have a lot of sata connections so if you have lots of physical drives you may have issues and require an additional sata or HBA expansion card... all in all 12xxx is a hot running expensive platform, slowly dropping sata support for more and more m.2 drives.. so if you don't need the horsepower stick with what you have. I would also mention AMD as a more cost effective option BUT: The only "modern" system I have is an amd 5900x and I would hessite to recommend it because of hardware and driver bugs that have persisted for years. I tried raid, stuttering, drives completely dropping out and only reappearing on reboot, terrible performance unless I loaded down one core... then it just worked... I guess it was power save and frequency scaling bugs. As soon as all the cores dropped bellow 3.6ghz drives vanished or hung. I ended up having to go non-raid. AMDs non raid drivers where SO bad AMD dropped the drivers and just provide Microsofts' ancient standard sata drivers with no chipset specific optimisations. After this I still got occasional random stuttering and random short duration windows freezes... turns out the amd equivalent of TPM (trusted platform) had bugs. I was using it for boot drive encryption... That bug was present from the beginning and only got fixed a month ago. After they fixed it they admitted there was a problem if they had admitted earlier I would have tried an add on TPM rather then the in built one but I had no way of knowing what was causing the freezes. Then I got audio issues, random stuttering unless I loaded down one core. Paradoxically increasing the soundcards hardware buffer (which should have reduced the stuttering actually increased it).. I ended up using tiny hardware buffers. Timing errors, dma or interrupt issues I guess. Same soundcard worked flawlessly on multiple intel platforms. Before all of these issues there was widespread well documented issues with usb randomly dropping out... but I purchased after that got fixed so I did not experience it myself. I was very happy with the cpu performance and value for money but the overall experience was not at all polished amd left a sour taste in my mouth. My 5900x experience was the most frustrating of any build I have done over the last 20 years and the lack of timely updates and acknowledgments of issues from AMD did not help... My experience with Intel is it just seemed to work. Now with the latest fixes from AMD things are not bad but I don't have confidence another driver or hardware related issue with not magically appear and take multiple years to fix... I just cant trust the platform in the way I can with intel. Oh and I almost forgot to mention 13 gen intel is around the corner... it will only be an incremental upgrade since it will be a refinement of 12 gen but that might explain why the seller is pushing hard for you to upgrade - so they can shift stock before it gets obsoleted in a few months. Unless you want the features of 12 gen intel stick with what you have and save a ton of cash for DIY builds or music. Long gone are the days of upgrading from say a 286dx 12Mhz to a 386dx 40Mhz and seeing a 2-3x performance uplift in a single cpu generation... now its more like 25% increase in 4 generations. Yes you get more cores in each generation but very little software will exploit all the cores so unless you are doing coin mining, massively parallel video rendering etc most of the cores will just sleep...
  9. jamesmking

    Deals

    mono has a multitude of advantages over stereo, both in terms of economics and practicality: mono is more "pure" than stereo. for sessions recorded on tape full width mono had better signal to noise ratio than half track stereo. you have more control over speaker placement, you get no cross talk, you can buy better sounding mono components for the same money as the stereo equivalents, your interconnect and speaker cable costs are halved as is the cable clutter almost all recordings before about 1958 are mono anyway, you can store twice as much music on your harddisk/ssd as stereo, stereo recordings often had mono mixes - because at the introduction of stereo many studios where unsure of if stereo would be popular due to its higher cost, and of course, had much more experience recording with mono. Many of the mono mixes are better regarded and more sought after than the stereo mixes from the same sessions. e.g. the Beatles... (https://www.chicagotribune.com/opinion/editorials/ct-beatles-mono-mixes-lennon-edit-20141003-story.html) do you critically listen and prefer music in 7.1 surround sound? no why because its artificial, complex and detracts from the music, its a gimmick.. then why listen in stereo,? Apply Occam's razor reduce to the simplest form use the original and best form... mono... mono ©️ the way it was meant to be played ... 🙂
  10. C2M1000170D has just become available again from radio spares. if you want to avoid mouser (currently out of stock anyway) or digikeys current pricing gouging of $9+ EACH. In radio spares select production pack not standard pack to see 1213 in stock minimum purchase 5 the price is still more than pre-silicon shortage levels but is low compared to other sellers.
  11. unfortunately now mouser, farnell and digikey now have the FQPF8N80C as obsolete and no longer manufactured...
  12. 0. lose your conscience 1. get an oem to make the thing for you (cheap as possible no need for quality/performance) 2. attach pointless bling to the oem thing (if you are out of ideas for bling try a university art department, get the students to do it as a project for zero cost. Offer the students a 10% discount on the final product as an incentive) 3. get a e commerce web site (students studying computer science should be able to make it for you again offer 10% discount) 4. bribe some reviewers (give them the product so they can give it to their mistresses) 5. get lots of media exposure (talk BS about your innovative product) 6. create a cult following (amongst the rich and famous. limited editions, special one offs etc) 7. sit back and watch the money roll in.... (get a swiss or caiman islands bank account) 8. get a good accountant and avoid all taxes 9. get your product ridiculed on head-case (who cares your are now a millionaire) 10. go back to step 1 when sales of your current product start to drop 11. if income still falls make a NFT version 12 if NTF does not make enough money invest in bit coin, lose all you money and go back to step 1 I hope this plan is detailed enough for you.... 🙂
  13. I'm tempted, it must be decades since I went to a hifi show of any sort. But I'm not sure of the point i am very happy with my mostly modern t2 and sr007 combination....
  14. well the missing bolts arrived and the free 20W laser... so I had some fun trying to burn front panel markings. After a few experiments I realised the default settings in light burn are insane...6000mm/min movement speed no way! and 0.1mm between steps does not provide good resolution and gives a streak effect on text and slightly jagged lines... I improved by changing the settings to two passes at 90% power, 0.05mm stepover and 1000mm/min. This gives a crisp result (crisper than my camera phone can show). The result is not a shiny as engraving with an actual 10degree 0.1mm engraving tool, so I will experiment a bit more. I guess I am still not quite getting all the way through the anodizing.
  15. I got bored waiting for the replacement bolts to arrive and so purchased my own and finished installing the missing bolts. Here is my first CNC project: Making my own Stax 5 pin sockets using ptfe design in vectric vcarve desktop: making some (ptfe) chips and no router bits broken... final result after deburring and running the drill holes all the way through: overall I am happy with the result. The tabs holding the piece into the material could have been smaller and after test fitting the pins the holes should have been 4.6mm rather than 4.5mm but I don't have a 4.6mm drill yet. other than that I have a working Stax socket 🙂 This first version uses 3 tools: 3.175mm end mill, 3mm drill and 4.5mm drill.... its slow and boring changing tools, so I remade the tool paths only using a 3.175mm end mill, ran the code and found the drill holes were smaller than expected. I measured the 3.175mm end mill... 3.13mm... hmm... so I updated the tool data base with the correct diameter and re-ran the cut again.... I realise now I have to measure all my tools and not rely on the size they claim. I could not find any metal m3 nuts that fit the threads but are small enough not to touch each other so I used nylon nuts instead. I tested the insulation between the closest pins pairs to each other and got 300Gohm at 5.5Kv.
  16. on further inspection the clamps held the work down ok, but the table is bowed downwards in the middle, hence the vibrations in mid way. I will experiment with the tape and ca glue. I also have purchased a thick spoil board which I will attach very firmly to the bed and level that. But I don't see much point in doing the levelling until I have put in the missing bolts which I cant do without some disassembly anyway. I also need to square the Y axis (dual motor) and square the spindle... all the axis come pre assembled - no bolts missing there and I did check all the bolts were tight. almost all the missing bolts are to things like limit switches, drag chain rails, thin guards to stop chips jumping onto the axis threads, bolts for the additional spindle holders etc. I would not run the machine if it did not feel the structural parts were not well bolted together. I could stop all the vibrations by putting weight into the middle of the work piece. The machine (other than the standard spoil board) feels really solid. the laser should arrive in 2 weeks or so. I hope 20W will be powerful enough, but its a free gift from foxalien for the missing bolts and scratches to the controller box.... I don't mind taking things slowly including the speeds and feeds i'm in no hurry - I have a lot of learning to do and a lot of experience to get. I know i'm going to break bits, ruin some work etc.. and im ok with that, hence the cheap bits and working a scrap materials. I was fascinated by wood work and metal work when at secondary school but I ended up studying computer science and university. I like the idea of making things, (I guess it was having lots of lego when I was a child) - and like the idea of making better looking front, top and back panels for my stax amps, so i'm viewing the entire thing as a learning experience a to keep me occupied now I have built all the stax amplifiers I wanted to.
  17. Thank you for the advice and support Kerry, I suspect the chineseium 2mm end mill is the problem.... rather than single flute it has lots of little burs on it and was garbage at clearing chips and sounded like shit at 10mm min cutting speed. I'm hoping single flute will be better. I have some single flute chinesium 3mm end mills and 6mm but I have not been brave enough to try them yet. Once I have got some experience I will get some good quality mills. I tried some engraving with a 30degree 0.2mm chinesium engraving bit and this worked much better no breakages and a lot nicer cutting sounds. I did some rate tests and got up to 160mm 0.022mm depth of cut without breaking anything. I found the line quality slightly degrades as the cutting speed goes up so I settled on 100mm min. I have not tramed the mill yet or made a spoil board or levelled it so I was not expecting perfect results but the engraving is not bad. The lines are a little thick for my liking (I made them 0.4mm wide in the cad) but I managed to cut through the anodizing without an issue at 100mm per min and 0.022mm depth of cut. Part of the e is missing in the volume text, but the text is quite small (which I knew would happen from the cutting simulation. I need a smaller angle engraving tool for the fine detail on the e, so I have ordered some 10degree 0.1mm engraving tools which the simulation shows will fill out the entire e). (sorry its slightly blurry just used my cheap phone could not be bothered to go slr and tripod) For software I tried fusion360 - gui and user experience is diabolical as a lecturer I can get it for free but I hated it. I settled on paying for vcarve desktop - it does what I want, is easy to use - I just wish it had adaptive tool paths. For sender software i'm using candle although I will probably go universal gcode sender. I just tried 3.175mm single flute end mill and got chatter and lots of vibration of the aluminium I was cutting when going above 0.1mm DOC at 250mm/min. I suspect this is because: 1. I have not levelled the supplied spoil board, 2 I only used 4 hold cheap down clamps (material 430mm long, 90mm deep and 10mm thick) and I think painters tape + superglue might be better, 3 my machine is missing half the bolts. (carton containing all the bolts and washers split open in shipping and about half of everything must have fallen out of the box on route) 😞 On the other hand I did not break the tool 🙂 So I'm pausing experimentation until the rest of the bolts and a thicker spoil board arrive, then I can level and make more meaningful experiments...
  18. Well I'm no longer a cnc virgin finished building the machine yesterday. Broke my first end mill today. 2mm carbide endmill trying to mill 27mm long ventilation slots in 3mm thick aluminium... first two slots went ok taking tiny nibbles at 0.2mm depth of cut and a feed slow increasing from between 10mm to 100mm per min. Then I got a little too ambitious with the feeds going for 200mm feed and 0.4 and then 0.6mm depth of cut. Instant SNAP I guess this is to be expected.... I did hear the sound of the cutting change a little before hand but did not react in time...Post mortem on the end mill shows it got clogged up... guess I need cutting fluid a single flute end mill and more experimentation... I literally had to use plyers to extract the broken end from the aluminium it got welded in. well just broke a second bit... 100mm feed 0.3 depth of cut is too much for the cheap chinesium 2mm endmill again the end mill bound and clogged up.... need to wait for some (hopefully better) single flute 2mm to arrive....
  19. a speed and feed calculator. https://fswizard.com/
  20. this stuff looks interesting Cermark Spray for making labels on steel, unfortunately does not work on aluminium- Starts at 25:32. marking aluminium with a lesser
  21. A few useful basic CNC beginners videos I have found. calibrating axis setting up a spoil board. problem solving issues guide to bits some speeds and feeds for aluminium and steel - starting at 20min 20secs
  22. Thank you Kerry. My plan, to begin with, is to modify existing hifi2000 cases and just cut holes for connectors and valve bases, do some engraving and more ventilation slots etc.. . I can't see myself scratch building a case any time soon, but I agree if I go down that route I will need more power and bigger tools. One thing that I am a little concerned about is the lack of software spindle speed control and I don't think there is a tachometer to tell you what the spindle speed actually is. But I guess I could get a hand held tach. I notice that most high power motors are water cooled. I wonder if I could use my pcs 480mm r(4x 120mm fans and 80mm thick) radiator 🙂
  23. I could not help but notice that the dead tree carcass machinists have a thread on wood machining. But dead trees do not make the best cases for stax amplifiers. So i'm a little surprised that there is no thread dedicated to CNC machining metal. The motivation for this thread was that I turned 50 years old a few weeks ago and for my birthday I decided to buy myself a CNC machine so that I could make my own cases for my stax builds. I decided to buy the foxalien Vasto, https://www.foxalien.com/products/cnc-router-machine-vasto?sca_ref=725103.t6qfXeHAnx based on not much more than I needed to machine 400mm by 400mm and the reviews on youtube are very positive. I'm waiting for delivery so I can't comment on if it is any good and I am a complete CNC newbie so I'm hoping this thread might become popular and eventually contain some advice for people who want to build cases for their amps. regards and best wishes james
  24. I have not ripped the telarc lps but I do have telarcs lps, cds and sacds issues of several classical recordings including the famous 1812 and the holst suites, Stravinsky firebird and pictures at an exhibition. I don't have a setup capable of playing back sacds without converting to pcm. I can bit for bit rip sacds. (hint early PlayStation 3 with early firmware could run alternative operating systems and could play sacds)... later firmware releases stopped this possibility and there is no way to downgrade after a firmware update. The telarc cd issues do suffer slightly from the down conversion... for example some of the cd issues do not use all 16 bits per sample. (My rme aes32e sound card has some analysis software and it shows the bottom 1 or 2 bits on some of the cd issues are not used and strangely the number of unused bits can vary between the channels!!). The sacd issues unfortunately do not give any details of how the conversion was preformed. Sound wise I find the lps more musical and a bit less muddled than the cds ripped to flac and played through my dcs elgar plus. However, there is not a lot in it and its possible that this is a limitation of the elgar plus - it was top end in its day but that was a loooong time ago. The sacd rips converted to 192K 24bit pcm do sound different to the cd, slightly less dynamic but more "cohesive" but this could be the effect of the dsd -> pcm conversion. Its also possible since the original recordings were 3 channel that they slightly tweaked the balance between the centre channel and the left and right to reinforce the centre a bit... Again the sacds don't give any details of any adjustments made to the mix... I have done transfers of my sheffield lab direct to disk lps - sheffield labs did release on them cd and I believe my recordings have better bass and more warmth and are more musical. The official issues do have a little more snap to plucked strings and possibly a bit better imaging. I run a highly modified garrard 401 with regenerative psu, upgraded bearings etc. But the official issue does have lower rumble than I can get from my garrard but the bass of the official issue is rather dry. If I run my recordings through izotope rx9 I can get rid of almost all the rumble and still sound better than the offical lp to cd transfers in the bass end. I suspect my cartridge is the limiting factor for the treble end. Running through the rme soundcards spectrum analyser I can see a fair mount of music above 20Khz in the lps which is cut off by the cd brick wall filter it looks like they did not low pass filter at 20k when doing the direct to disk. Extension past 20k varies from disk to disk - confederation does not have a lot, however the three Harry James lps have quite a bit due to the harmonics in the trumpets and brass instruments in general, cymbals etc. I am really sensitive to bass quality and I almost never play the official cds - I play my lp transfers. I also have also recorded some of my opus 3 lps and compared to dsd downloads available from dsdfile and in a few cases the offical opus 3 cd issue. (dsd file got the original master tapes and went direct to dsd) here my lp rip setup to the dcs 905 adc can't complete with dsdfiles' top end tape deck playing the original masters - the dsd macro dynamics are better, stereo imaging is better, treble extension is better and snappier, bass is deeper and more solid. Again there is some output above 20khz on the lps and dsd but it falls off above 20khz fairly rapidly which I guess is just the response of the analog tape deck used in the original recordings or possibly some mild low pass filtering. The potential problem with telarc sound stream onto dsd is, yes sacd has a higher sampling rate than cd but dsd has lots of high frequency noise which either need to be filtered on playback or "ignored" - if your playback system has little bandwidth above 20khz. Secondly you still have do do maths to convert from soundstream to dsd- the bit format for sacd and so will not give you a bit for bit copy of the original. I can't make a fair comparison of the cd vs lp vs dsd sound since my setup in London does not have native sacd support and so I reply on Jriver media player converting my sacd rips from dsd to 192K 24bit pcm. I do have a dsd capable dac - dcs elgar plus, but it can only do dsd via 3 bnc connectors and I dont have anything which can take sacd and provide that output (ironically my dcs 905 adc also supports recording dsd and has the same 3 bnc output). The rationale for sacd/1 bit recording was that you don't need to brick wall filter during recording and that its these filters that damage the sound. The filters cause phase shifts and also almost all symmetrical filters have pre ringing - i.e. echoes of the sample before the sample is played. However, with dsd you still need filtering on playback... In fact both the dcs elgar plus and dcs 905 adc have selectable filters for pcm and dsd for playback and record respectively. Considering non audiophile labels for example the Philips remasters of 1970s classical music - e.g. Marriners complete Mozart symphonies vs my lp transfers there is absolutely no contest. Many of the official cd transfers where from lp - if you spectrum analyse you can see low frequency warps and you can even hear the occasional click and pop of dust. The cd transfers from philips have awful treble, glassy, hard and "stringy" typical early cd sound - are lean, lack of bass almost no warmth. This is particularly bothersome with some of the early symphonies that are mostly just strings and the result is the cds are bit painful to listen to. My Lp rip vastly more musical and better balanced. Philips uncaring cd transfer vs careful lp transfer sound as different as stax sr407 vs sr007. I have not riped any of my lps to dsd for the simple reason I have no ability to edit the results without converting to 192K 24 bit pcm editing in pcm and converting back - which is not a bit accurate conversion... however unfortunately this is how many dsd recordings are edited. The dcs 905 also has the ability to do 384Khz but this outputs in a special format for a certain nagra digital recorder and I have not bothered to write any software to convert nagra 384K to pcm 384K although it should be possible and should be bit for bit accurate since the nagra simply spreads the stereo 384K over 4 192K channels as it does not have enough bandwidth to record 384K on two channels.... but I don't have a dac which can do 384K anyway. So for me, my general feeling is: well made original recordings on tape transferred expertly from the original masters to sacd or cd would require a ridiculously expensive lp setup to rival - definitely £20K+ for cartridge, arm, deck and phono stage even without factoring in the adc. Mass market classical cd issues of analog recordings different story.
  25. the telarc recordings were half speed mastered with no transformers in the signal chain and a frequency response down to 12hz or so with no compression or limiting or any type. They tried to get the entire signal chain as high quality as possible and muck around as little as possible, right down to using only using 3 high performance microphones and not multi milking, spot lighting etc. They designed for proper hifis and not for the average consumer grade kit. The soundstream digital system also sampled at a higher frequency than the competition (or cd), and unlike early cds, telarc could actually do editing and splicing digitally whereas all the major record companies took the digital recorded it onto analog tapes edited the analog tapes and then played the edited tapes and digitally re-recorded (but still lied and claimed the signal chain was DDD throughout)... or recorded on their didital system and then converted to soundstream edited and then converted back. Even when DAT and proper computer editing took over the sample rate was higher than cd and had to be down converted and anti aliasing filters applied... the stream of data off cd also has a delay between the right and left channels. many early cd players did not correct for this which I think was one of the reason the treble was so sharp on the early cd players. A few high end players ended up having two dacs and a time delay circuit to realign the left and right channels. But I never got to hear one at the time. In many many cases the record companies transferred analog masters to DAT, and then threw away the analog master tapes... DAT had almost no error correction built in and a few years down the line the DAT tapes were unreadable and the master tapes were gone. So many of the cd reissues of classic analog recordings where actually digital recordings from the lps anyway, and the lp system they used for play back was garbage, the "remasters" sounded bad then and they still sound bad now. I could make far far better recordings from my lp system going through a dcs 905 adc at 24 bit 192Khz sample rate. Telarc digital on lp vs philips "remasters" of classical lps on cd... no contest. I played the telarc 1812 no issues on a decca black with decca pod, modified tie wire system and a proper line contact diamond. My ortofon cadenza bronze has no issues either and thats a moving coil. Both on a heavily tweaked haddock 242 unipivot arm. (ALL hadcock 228 arms had incorrect geometry and the aluminium arm tube versions lack the weight to properly press down on the inverted uni pivot)). And of course ALL telarc sound stream recordings have to be down sampled and anti aliased to go onto cd... The sound stream digital was far better sounding than the early Philips PCM - which DID NOT have even 16 bit resolution... it was about 12-14 bits + deliberately added noise because the 14 bits was not that linear and low level signals had about 25% - 75% distortion and looked like square waves.. apologises for incoherent rambling but for me the message from sound stream was make the record chain as good and simple as possible, make as few compromises as possible and don't muck up the sound with filtering or compression and aim for an audience with proper hifi... lessons many recording companies never learned and still need to learn today. I also wonder if the average person listening to music through their mobile phone gets higher auto quality than the average person in the 1960s or even 1950s... (when a good hifi seemed to be a part of most middle classes lives). I have listened to a friend playing some music through some cheap Bluetooth speakers via their mobile and I seriously wonder if (apart from the surface noise) the sound was better than a 1940s 78 on a good player. James
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