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Gieseler Audio

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Everything posted by Gieseler Audio

  1. I’m not back at work until tomorrow so I will do some testing later in the week.
  2. Hi Roy, yes it is definitely something I will be looking at. Once I get back to work (on holidays at the moment) I will try some listening tests to confirm if a discreet style pre regulator in a DAC makes a difference or not.
  3. Hi Guys, hey both names sound good. I was thinking of “KD” as in Kraftwerk Discreet as it uses discreet parts instead of the usual monolith regulator
  4. NEW GIESELER ENHANCED PSU Well I thought it was time to re look at my PSU range. The current range IMHO is still competitive & up to date with current tech but I did think the Gold Tune Enhanced version could be improved a bit in terms of sound & more competitive pricing. It was a bit of a struggle to hear a sound difference between say the Gold Tune & Gold Tune Enhanced versions so the $100 price jump was not really justified. So far all my PSU’s use high quality/low noise LDO (low drop out) monolithic regulators. This is the area where the most development is happening with new regulators. Now looking critically at LDO regulators they do have one aspect that is not the best for audio quality – output impedance. To minimise the voltage drop all LDO regulators run the regulators series device (Mosfet or Transistor) in a common base arrangement, that is the collector (or drain) is the output. This gives the lowest voltage drop but also has high output impedance which is not good for a PSU. This new enhanced PSU is running the series device (Transistor) in “Emitter Follower Mode”. This gives very low output impedance but it needs more voltage at the input due to the bigger voltage drop across the transistor. Also there has been talk on some UK forums that the usual monolithic regulators using lots of negative feedback do tend rob the sound/music a bit. In light of all of this I have come up new design using all discreet components & the pass transistor is now running in “Emitter Follower” mode hence nice low output impedance. Also it is a non feedback design based on a very low noise red LED string voltage reference being fed with a constant current source. The raw DC front end of the design is the same as the Kraftwerk Gold Tune which is well optimised IMHO. It does not have the thermal cut-out, short circuit protection & huge 4 Amp rating of my other designs but these options are not normally required when running Klein/Gross/Fein DAC’s which only draw a few hundred milliamps. Does it actually sound any better? Well I have only done a few brief comparisons against a standard Kraftwerk PSU & it definitely sounds better than that. After Christmas I will try some critical comparison with the Gold Tune version & old Enhanced versions & report back. The current rating is 2A & so plenty for Klein III/Gross/Fein DAC’s. Also with the Gross/Fein DAC’s it is best to use the 16v 2.5A transformer (in photos) as they draw more current. The Klein III will work fine with the usual 12v transformer. The 16v transformer has another nice option which a direct mains earth connection so when using this PSU negative side is now at mains earth. John Swenson of Uptone Audio fame is a big fan of having a PSU negative output connected to mains ground. Well there are few SNA’s members who are already using this PSU so maybe they can add some comments. Due to the massive amount of Nichicon Gold Tune capacitors the red LED’s run for quite a while after the PSU is switched off – see photos. They are currently in stock & the cost is $500 including shipping.
  5. I would assume they will all work but I have only tested it with Flacs & waves. Make sure you install the Amanero Windows 10 driver from here. https://amanero.com/drivers.htm
  6. Andy at HiFI Repair Services is excellent, located in Ashmore so not too far from you https://www.hifirepairservices.com.au/
  7. Item: 2 x ScanSpeak 15W/8530K-00 5.5" Revelator Woofers Location: Gold Coast QLD Price: $400 Item Condition: new Payment Method: Direct deposit, Paypal or cash on pickup Extra Info: I brought these for a project that never happened. Absolutely brand new, unused & only open for photos. Price includes Express Post shipping Australia wide. New price is $600 + shipping https://www.wagneronline.com.au/scanspeak-15w-8530-k00/ps/ https://www.madisoundspeakerstore.com/approx-5-woofers/scanspeak-15w/8530k-00-5-revelator-woofer-low-qts/ ScanSpeak 15W/8530K-00 5.5" Revelator Woofer - Low Qts The 15W/8530K is a 5.5" Revelator mid/woofer. It features a non-resonant cone and dust cap structure, dynamic linear suspension, SD-1 magnet system, "Grasshopper" cast chassis with maximized air flow and resonance terminating mounting system. Less resonance in all structures, lower compression and higher linearity, faster termination of excess energy and higher sound pressure capability make the 15W have more musical and dynamic capability than any other 5 ½" we know of. Wonderful bass in a small box! · Outside diameter: 148mm · Cut out: 125mm · Depth: 71mm · 25.4mm = 1" = 2.54cm Box suggestions: 0.15 cubic foot sealed box with 20% filling for an F3 of 90Hz 0.35 cubic foot box with 1.5" diameter vent by 6" long for an F3 of 50Hz
  8. No - it is a 12v fixed regulated PSU that suits the Fein DAC. However if you want a 15v linear low noise PSU I do make one of those.
  9. Hi Matt, I'm mainly looking at a custom case as the current Fein ones require a lot of metalworking & the panel production is fairly involved & time consuming. The goal is to have nice finished cases sitting on the shelf & I can just stick to the electronics side which I really enjoy. The Klein & PSU series use a simple Hammond case that the pcb just slides into but they don't make them in a big enough size to suit Gross, Fein etc. Anyway I am going to use a big Japanese company for the custom ones & they have a good range to choose from. They also do the cases for Uptone Audio.
  10. Item: GIESELER Fein DAC + Kraftwerk Enhanced PSU Location: Gold Coast Price: $1500 Item Condition: new Payment Method: Direct deposit, Paypal or cash on pickup Extra Info: GIESELER Fein DAC USB + Kraftwerk Gold Tune Enhanced PSU package - NEW I have found another Fein DAC (USB only version) so I'm offering it as a package with a Kraftwerk Gold Tune Enhanced PSU. This combination is equivalent to the current Fein II model. It is a new build & comes with the normal two year parts & labour warranty. The Fein & Fein II use the same firmware so this comes with the latest June 2019 version. The remote control is the newer version so has a little better off axis performance. For the record the Fein & Fein II is the same design/circuit except the Fein II has the built in Kraftwerk Nichicon Gold Tune PSU built in. By combing a Fein with the Enhanced Kraftwerk PSU you end up with the same higher quality sound you would get with a Fein II. This package represents excellent value as the Fein DAC listed for $1750 & the Kraftwerk Gold Tune Enhanced is $550 so $2300 total. The current Fein II USB (only version) lists for $2000 so you are still saving $500. This is definitely my last earlier version model so there will be no more deals like this for a while. Build date is 27/08/19 Price includes courier delivery Australia wide.
  11. Thanks guys! Matt RE big transformers in the Fein DAC. Yes I did try them & the early PCB's had a dual footprint that suited both types of transformers. It was actually an option on purchase. From memory we were struggling to hear the difference so I ended just permanently running with the smaller transformers. However the performance on the Fein II is getting so good now it might be worth trying the bigger transformers again. Just finding the time to do all the critical comparisons & in the reference system is the problem. OK current out transformers. It is a toroidal type using a nano crystal core & fully shielded case - cost is about $100 US each.
  12. Hi Matt, OK why the Gross was discontinued. The Fein was designed to be a more economical version of the Gross & both models were to coexist. It would give people a slightly cheaper option but with similar features. The Fein used the AK4493 which was the number two AKM chip at $13 vs $78 for the top AK4497 used in the Gross. The transformers were the other obvious area to save money on in the Fein. The Fein transformers are $35.67 US$ each vs $80.38 US$ each for the ones used in the Gross. That worked to be roughly a $200 aus $ saving in parts cost for the Fein but I needed a bigger gap to seperate the model range so I reduced the profit margin on the Fein. OK so I now had a sub $2k model with similar features to the flagship but with (supposed) slightly lower performance. Next move was off to Lenehan Audio to do some listening on a reference system. $25k speakers + $25k power amp, fully treated room & power regeneration plus four experienced listeners. We started with a well run in Gross & everyone agreed that it sounded very nice. Then I said, can we have a quick listen to my new model (the Fein) Well Mike Lenehan (the most experienced/critical listener) was shocked - wow - now that sounds better! Is that your new top model? - er, um no it is supposed to be the new number 2 model. OK I thought the only technical difference between the two models was the DAC chip & output transformers so why the better sound from the lower cost items? Transformers wise maybe the smaller sized ones in the Fein just match better to the tiny built in op amps in the DAC chip. In electronics bigger is not always better. DAC chip difference. Well there is a least a bit more of a logical explanation here. Even tho the AK4493 is down a notch compared to the AK4497 is it a much newer chip & has some technical improvements. eg auto DSD detection which the AK4497 does not have. The AK4499 uses the same auto DSD detection. My programmer who writes the DAC firmware code insists that the AK4493 is much better to work with & has quite a few improvements which help with the programming. It is interesting too that Esoteric are now using the AK4493 in their new high end models. Anyway back to the question - why discontinue the Gross? Well it was a bit of a tricky situation as I really could not have a lower range model sounding better could I? Fortunately about the time the Fein came out the Kraftwerk PSU’s were being used to Enhance the Gross so that combination boosted the Gross ahead again. Then came the Fein II which intergrated the Kraftwerk PSU all in the one case & that pushed it ahead again of the Gross + Kraftwerk combo so at that point it was a logical choice to discontinue the Gross. Phew! sorry for the long - winded explanation but that should make it a bit clearer. Oh the joys a being a DAC designer!
  13. Hi Matt, the sound quality seems excellent in a good reference system I recently heard it in. What I need to do is also compare it to my latest Fein II in the same system & then I can get a comparison on the SQ difference. The first prototype used op amps (as per eval board design) but in IMHO I'm now getting better results with some custom transformers that suit current out DAC's.
  14. Hi Matt, well I’m making steady but slow progress. I’m on the third prototype now & it is sounding pretty good. Unfortunately it is a very complex build with eleven discreet PSU’s just for the DAC chip alone. Currently lots of jumper cables on the pcb so the final production model will need a four layer board. Also it will require a custom aluminium case. In light of all that it will end up being a fairly pricey product. Minimum $5 to $6k price range & probably not ready until feb/march next year.
  15. Thanks guys. I forgot to mention I’m using the Mosfet in a “source follower” configuration & with some compensation so it ends up with extremely low output impedance over a wide bandwidth. At 18v output with no load & then at 4A load the voltage drops by less than 100mv. I will post some measurement photos tomorrow. The next step is to actually power a DAC with it & see it sounds. With the on board trimmer the voltage can be set from 12v to about 18.5v to suit the application.
  16. I have had quite a few enquiries about a suitable linear PSU for i5/i7 NUC's but up until now have not been able to come up with anything due to the higher voltage/current requirements. This is a brand new design that should fit the bill. It uses a unusual "active bridge rectifier" which improves efficiency quite a bit for a linear design. The other advantage is diode switching noise is almost nonexistent. The reason for this is the normal diodes are replaced with super low on resistance 90A Trench Mosfets that are switched on during the "0v" part of the incoming AC sign wave. This control switching is performed by a Linear Technology active bridge controller. The bottom line is you end up with a very efficient bridge rectifier with almost no switching noise at all. The regulator is a new discreet design using a high current 82A Toshiba Mosfet controlled with a voltage reference. I have also added short circuit protection which is unusual for a discreet design. Power is provided by an Australia approved Tortech 17v 5A external transformer. Main filter capacitance is 26,800 uf of Nichicon Gold Tune caps which is the same as the Kraftwerk 12v 4A Gold Tune series. Noise level is extremely low & similar to a Kraftwerk 12v 4A Gold Tune. Output is 18v at a maximum current of 4A. Cost is $500 which includes Express Post delivery. One unit in stock with a lead time of about 4/5 days for more orders.
  17. Actually that looks like the GA-408 Philips 22GA408 platenspeler info. WWW.PICKUPNAALDEN.COM
  18. Item: Uptone Audio USB Regen Location: Gold Coast Price: 135.00 Item Condition: mint Payment Method: Pickup, Paypal, Bank transfer. Extra Info: was purchased for testing purposes & only briefly tried once. Note comes with original power lead (USA plug) so you will need to change power plug or get a Aus / IEC power cord - very cheap. Price includes Express Post shipping
  19. Just letting everyone know that the new 2006be10 should only be used with Linux systems. It performs very poorly with Windows 10 & has lots of issues. The new default CPLD_for_1080 & DSD515x48x44 is perfect for Windows 7 & 10.
  20. The Fein II will actually drive headphones directly but you will need a RCA or XLR to 6.5mm adaptor cable. The power available is not a lot but with efficient headphones reasonable good levels are obtainable. Definitely worth a try.
  21. Hey just a thought. I currently have my 3-input demo Fein II DAC in Melbourne so you are more than welcome to try it in your system & see if you notice a worthwhile improvement. I would need to know ASAP tho as it is scheduled to go to Brisbane on Monday. It is currently with SNA member Mat-With-one-t in Thornbury It is a little over your budget but I could certainly do an attractive price being a demo unit. Anyway something to consider. Cheers Clay
  22. Well actually that is your board - It looked so good when I finished building & testing it yesterday I thought it would be good to post some photos.
  23. Just in case anyone wants to see whats inside. There have been a few little component changes/improvements recently Main Nichicon Gold Tune capacitance up from 10,000uf to arround 15,000uf. Also a few regulator upgrades. It may look a bit sparse but that is because it is a deliberate minimalistic design using high quality parts. The critical VREF capacitors around the DAC chip are Nichicon Fine Gold series with a massive 2,200 uf of capacitance. Muting uses solid state photo mosfet relays which are super fast & silent. The Amanero USB board has it’s own ultra low noise regulation using a premium Linear Technology regulator. All components are hand soldered with low temp silver loaded solder. I find this actually sounds a bit better than the usual 200+ automated baking process & long term reliability is also increased.
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