Posted: March 17, 2013 in Home Page


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When new information is added it will be shown below in the ‘whats new‘ section below.

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What’s new ?

updated 08-17: Beyerdynamic DT1770 measurements, evaluation and modification
updated 08-11: Beyerdynamic DT1990 measurements, evaluation and modification
> added 07-13: vintage Sennheiser HD420 SL restoration and evaluation
> added 07-11: Sennheiser HD 4.40 BT measurements and evaluation
> added 06-16: 1MORE Triple Driver Over-Ear measurements and evaluation
updated 06-16: NAD VISO HP50 added passive filter schematic
updated 06-15: measurements of recent Romanian produced HD58X
> added 06-04: Now offering to build you a passive filter for specific headphones
> added 05-19: Grundig EE1178 (BlueTooth) measurements and evaluation
> added 05-19: Denon AH-GC20 (B.T. / N.C.) measurements and evaluation
> added 05-15: Bose QC35-II (B.T. / N.C.) measurements and evaluation
> added 04-03HIFIMAN HE35X measurements and evaluation
> added 03-31: AKG K701 measurements and evaluation
> added 03-10: Sony WH-1000X-M3 (B.T. / N.C.) measurements and evaluation
> added 03-09Sony WH-CH700N (B.T. / N.C.) measurements and evaluation
> added 01-24: HIFIMAN Edition XX measurements, evaluation, modification
> added 01-12: AKG K7XX (Massdrop) measurements and evaluation
updated 01-02: Superlux HD681 measurements
updated 12-27: Massdrop HD58X modifications article
> added 12-08: Marshall Major II Bluetooth measurements and evaluation
updated 11-18: Some additional info on Koss KSC75 earphones
> added 10-21: A for sale section where some reviewed gear is up for sale
> added 10-17: Beyerdynamic T51p measurements and evaluation
updated 10-07Beyerdynamic Custom One Pro with COPPlus measurements.
> added 09-29: NAD VISO HP50 measurements and evaluation
> added 08-26Beyerdynamic Custom One Pro measurements, evaluation and modifications
> added 08-25: Pioneer SE-305 measurements and evaluation
> added 08-19: Campfire Audio Cascade measurements and evaluation
> added 08-18: Audeze LCD-4z measurements and evaluation
> added 08-17: Sennheiser HD820 measurements and evaluation
> added 08-13: Powerbank output keep-alive circuit for powering low current devices
> added 07-02: MrSpeakers Ether measurements and evaluation
> added 07-01: Superlux HD687 measurements, mods and evaluation
updated 07-01Sennheiser HD58X Jubilee added some plots
> added 06-27: AKG K92 measurements and evaluation
> added 06-26Beyerdynamic Amiron Wireless measurements
> added 06-25: Sennheiser HD599 measurements
updated 06-25Sennheiser HD58X Jubilee measurements and evaluation
> added 06-24: Audeze LCD-2 Classic measurements
> added 06-24: Audeze LCD-MX4 measurements
> added 06-23: Sennheiser HD569 measurements
> added 06-23: HIFIMAN Sundara measurements
> added 06-23: Final D8000 measurements and evaluation
> added 06-21: HIFIMAN Ananda measurements and evaluation
> added 06-08: Mitchell & Johnson  JP1 DJ measurements
> added 05-26: Beyerdynamic DT 880 Edition treble modification
updated 05-20: 3rd-party-plots useful links to other measurement sites
updated 04-24: Beyerdynamic DT 880 Edition (250Ω) measurements
updated 04-07: Kameleon filter list.
> added 04-01: Superlux HD671 measurements and evaluation
updated 03-17: Passive filter for Master & Dynamic MH40 added
> added 03-14: Master & Dynamic MH40 measurements
> added 03-12: Beyerdynamic DT 880 Edition (250Ω) measurements
> added 02-17: Superlux HD672 measurements and evaluation
> added 02-10: Takstar PRO 82 monitor measurements and evaluation
updated 01-21: Superlux HD688 production version measurements


updated 12-26: pdf with more Sennheiser HD58X measurements and experiments
> added 12-21: Sennheiser HD58X Jubilee (Massdrop) measurements and impressions
> added 11:25: MrSpeakers ÆON Open measurements and impressions
> added 11:23: Focal Clear measurements and impressions
> added 11:02: MrSpeakers ÆON Closed measurements
> added 11:02: MrSpeakers Ether flow (open) measurements
> added 11:02: MrSpeakers Ether C flow (closed) measurements
updated 11:02: Sennheiser HD660S measurements with HD600 comparo.
> added 10-28: HIFIMAN Susvara measurements
> added 10-28: Grado GS2000e measurements
> added 10-28: Audeze LCD-4 measurements
> added 10:26: JBL E40 BT measurements
> added 10:25: Sennheiser HD800S measurements
> added 10:24: Sennheiser HD660S measurements.
updated 10-08: Denon AH-D600 modifications measurements.
updated 09-21: Sennheiser HD250 linear II measurements.
updated 09-19AKG K501 measurements with some experiments.
> added 09-08AKG K501 measurements.
> added 09-06: HIFIMAN HE-6 (early 4-screw version) measurements.
> added 08-10: Creative Sound BlasterX H7 Tournament measurements.
> added 07-20: HIFIMAN HE1000 measurements
> added 07-19HIFIMAN Edition S and Edition X measurements
> added 07-18HIFIMAN HE400S and HE-560 measurements
updated 07-17: HIFIMAN HE400i measurements
> added 07-16: Beyerdynamic T1 (mk2) and T5P (mk2) measurements
> added 07-16: Beyerdynamic DT 1770 Pro and DT 1990 Pro measurements
> added 07-15: Focal Utopia and Listen measurements
> added 07-14: Focal Elear measurements
> added 07-13: Sennheiser Momentum 2 (over-ear) measurements
> added 07-12: Sennheiser HD250 linear II measurements
> added 07-11: Sennheiser HD630VB measurements
> added 07-10: Sennheiser HD700 measurements
> added 07-10: Sennheiser HD 2.20 measurements
> added 07-09: V-MODA crossfade II wireless measurements
> added 07-08: V-MODA Crossfade M100 measurements
> added 07-08: Final Sonorous III measurements
> added 07-07: Denon AH-D600 measurements
> added 07-07: Audeze Sine measurements
> added 07-05: Audeze LCD-3, LCD-X and LCD-XC measurements
> added 07-05: Meze 99 classics and 99 neo measurements.
> added 07-04: Audeze EL-8 open, EL-8 Titanium and LCD-2
> added 07-03: Beyerdynamic Amiron measurements.
updated 07-01: Foobar Tutorials
updated 06-23: Cables article
> added 06-17: Balanced attenuators in attenuator and power-amp sections.
updated 06-04: Foobar tutorial part 2
> added 06-03: Battery circuit change for Kameleon and Kameleon 2 portable amps.
updated 06-01: supported Kameleon modules list
updated 04-17: more Roland RH-300 measurements.
> added 04-08: Roland RH-300 measurements.
updated 03-18: changed the how to interpret graphs tree-structure
updated 03-12: added info to the how to interpret graphs article
> added 03-08: t.bone HD 990 D headphone in measurements
updated 03-03: supported Kameleon modules list
> added 03-01: Superlux HD687 (prototype) measurements
updated 02-18: Fostex TH-X00 and Fostex T50RP mk3 measurements
> added 02-11: Fostex TH-X00 (Mahogany) in measurements|Fostex
> added 02-07: Fostex T50RP mk3 in measurements|Fostex
> added 02-05: Superlux HD688 (prototype) measurements
> added 01-24: Compressing DSD files with Wavpack 5 tutorial
updated 01-09: Kameleon-2 Desktop and Portable amp build manuals
updated 01-02: Headphone attenuator adapter article


updated 12-31: Foobar tutorials
updated 12-08: ATH-MSR7 turned out to be fake, moved to crap section
> added 11-26: Dedicated Kameleon page
updated 11-16: HiFiman HE-350 measurements
updated 10-29: supported headphone list for Kameleon
updated 10-20: HiFiman HE-350 measurements (2nd HE350 + seal)
> added 10-19: Veclan Monk+ in measurements
> added 10-19: FAKE audio-technica ATH-MSR7 measurements
updated 10-12: Re-arranged the measurements section
> added 10-08: fix for HiFiman HE-350 treble  in measurements|HIFIMAN
> added 10-08: HiFiman HE-350 measurements in measurements|HIFIMAN
updated 10-03: Kameleon articles (more filter modules added) in schematics|headphone
> added 09-17: Sony MDR-100AAP measurements in measurements|Sony
> added 09-15: Pre-production Superlux HD581 in measurements|Superlux
> added 09-12: Sony MDR-1A measurements in measurements|Sony
> added 09-04: In-line Kameleon manual
updated 09-04: Kameleon-2 desktop and portable amp manuals
> added 08-24: My views on ‘neutral sound‘ in learn
> added 08-06: Influence of Fletcher-Munson on listening pleasure in learn
> added 07-28: Taming the treble article in headphones|taming the treble
updated 07-27: How to interpret graphs, added inner|fidelity compensation.
> added 06-19: Philips SHB-9850NC measurements in measurements|Philips
updated 06-01: headphone power table in learn|articles
> added 06-01: Beyerdynamic DT150 measurements in measurements|Beyerdynamic
updated 05-26: Headphone adapter article in learn|Power-amp-adapter
updated 05-21: Superlux HD662-EVO measurements in measurements|Superlux
updated 05-14: info about SMPS vs LPS power supplies in learn|power supply types
>added 05-04: Ausdom ANC7 measurements in measurements|Ausdom
>added 04-15: Schematic G1217 project Ember rev. 2.1 in schematics|amplifier
updated 03-09 AudioQuest NightHawk cable in measurements|AudioQuest
>added 03-03: AudioQuest NightHawk measurements in measurements|AudioQuest
> added 02-23: Kameleon 2 DESKTOP build manual
updated 02-21: Kameleon 2 PORTABLE build manual
> added 01-31: Superlux HD662-EVO measurements in measurements|Superlux
> added 01-28: HiFiMan HE-400i measurements in measurements|HIFIMAN
> added 01-24: Beats Studio Wireless measurements in measurements|Beats
updated 01-24: Ausdom M05 measurements in measurements|Ausdom
> added 01-08: Sennheiser HD700 passive filter in schematics|headphone related
———————— 2016 ————————
updated 12-24: Some headphone measurements have been updated.
> added 12-24: Bose Quiet Comfort 25 in measurements|Bose
> added 12-19: Bravo Ocean modifications in schematics|amplifiers
> added 12-16: Kameleon-2 article.
updated 12-13: Philips cityscape uptown in measurements|Philips
updated 12-02: Superlux HD681 and HD681-EVO in measurements|Superlux
> added 12-02: Superlux HD572-SP measurements in measurements|Superlux
> added 11-19: Passive filters for some Hifiman models in schematics|headphone
> added 11-18: Sennheiser HD800 measurements in measurements|Sennheiser
> added 11-13: Foobar tutorial part 3 SACD plugin in digital|software
updated 11-12: Yet some more measurements in Sennheiser HD650 modifications.
updated 11-02: Foobar tutorial about playing DSD in digital|PC software.
> added 11-01: created a download section with articles/schematics etc.
updated 10-18: Even more measurements on Sennheiser HD650 modifications.
updated 10-15: Foobar 2000 for dummies in digital|PC software.
updated 09-17: added info about square-waves in explanations|how to interpret graphs
updated 09-17: Information about listening levels in learn|power etc.
> added 09-13: Extensive measurements on Sennheiser HD650 modifications.
> added 09-12: Passive inline filter for some HIFIMAN headphones
> added 08-23: Some ramblings about DR, distortion and SPL in learn|DR
updated 08-13: Olive-Welti target curve in explanations|how to interpret graphs
updated 08-11: Headphone correction filter article
> added 06-29: Info about headphone attenuators for IEM’s and sensitive headphones.
updated 06-17: information about power supplies in learn|power supplies
updated 05-23: Headphone correction filter manual in schematics|headphone
> added 05-02: Schematics for the ‘SeNNator‘ amplifier in schematics|amplifier
updated 05-07: Kameleon article in schematics|headphone
> added 05-02: Measurements of Sennheiser HD600 and Ultrasone HFI-780
> added 04-23: Schematics for the latest versions of several G1217 amps.
updated 04-19: Philips uptown article (added info about securing the pads)
updated 04-12: Added some info on tubes in amplifiers|hybrid
updated 03-21: Kameleon and filter article in schematics|headphone
> added 03-08: A detailed article about the Superlux HD562 in pdf format.
> added 02-28: Beyerdynamic DT770Pro-250 and DT990Pro-250  in headphones|measurements
> added 02-27: Grado SR125i measurements in headphones|measurements
> added 02-27: AKG K612 measurements in headphones|measurements
> added 02-18: Superlux HD562 measurements in headphones|measurements
updated 02-07: FiiO and Sansa measurements in Digital|Digital Audio Players
> added 02-06: Schematic of project Solstice in schematics|amplifier
updated 02-04: Added plots from Kameleon amp in schematics|headphone
updated 02-02: Philips SHL9505-GY plots in headphones|measurements
> added 01-28: Info about HD650 pads in headphones|measurements
updated 01-26: Info on rectifiers in learn|power supply/filters
> added 01-21: ARTA setup guide by BMF in learn|articles
> added 01-20: my views on ‘burn-in‘ in learn|burn-in
updated 01-11: the headphones|recommended ones section.
———————— 2015 ————————
updated 12-28: The AKG K518-DJ in headphone|measurements
> added 12-24: Philips Cityscape Uptown SHL9505 in headphones|measurements
updated 12-24: changed the layout of headphones|measurements
> added 12-16: Schematic of a tube buffer circuit in Schematics|Amplifier
> added 11-16: Some info about measurements and disclaimer in headphones|measurements
> added 11-13: Article about dB: do deciBells ring a bell ? in learn|do decibells
updated 10-04: Philips A5 Pro with PCU110 velours pads measurements in headphones|measurements
> added 10-01: Philips A5 Pro measurements in headphones|measurements
updated 09-10: Kameleon article (added Sennheiser Momentum)
> added 09-04: Some extra info about getting a good ‘seal’ of headphones in a few pages.
> added 08-20: Project Polaris schematic in Schematics|Amplifier
> added 08-14: Measurements of Sansa Clip Sport, Fuze and FiiO X3 in digital|DAP
updated 08-10: Some info added in schematics|amplifier section
updated 08-09: headphone power table
> added 07-13: AKG K181 / K400 / K500 & Beyerdynamic DT250-250 in headphones|measurements
> added 07-09: Superlux HD-685 evaluation and modifications in Schematics|Headphone
> added 07-05: DIY Woodies made by ‘Stratocaster’ in headphones|measurements
> added 06-25: Philips SHP-9500 and Superlux HD685 in headphones|measurements
> added 06-13: Philips Fidelio X1 in  headphones|measurements
updated 06-11: Beyerdynamic DT1350-SL pad measurements in headphones|measurements
> added 05-29: Audio Technica ATH-M40X modifications in  headphones|measurements
> added 05-27: Audio Technica ATH-M40X in  headphones|measurements
updated 05-22: Headphone correction filter article in Schematics|Headphone
updated 05-19: headphones|recommended ones page.
updated 05-14: added headphone(s) to the Kameleon article in schematics|amplifier.
updated 05-14: Kameleon article and headphone power table
> added 04-28: Kameleon portable headphone amplifier article in schematics|amplifier
> added 04-19: Some information about regulators in Explanations|power supplies.
updated 04-09: Tascam TH-02 mods in  headphones|measurements
> added 03-19: An section about efficiency in Explanations|power, impedance.
updated 03-18: The Explanations|how to interpret graphs section with Olive-Welti curve.
> added 03-17: Beyerdynamic T90 passive highs/peak filter in schematics|headphone.
> added 03-16: How LOUD we listen, what power we need for it ?  Explanations|power, impedance.
updated 02-17: Beyerdynamic T50P/DT1350 pad measurements in headphones|measurements
> added 02-10: added Sunrise-III and Horizon-III in schematics|amplifier
updated 02-02: updated version of the impedance/resistance article in learn|power, impedance .
> added 01-26: Tascam TH02 and AKG K550 measurements in headphones|measurements.
updated 01-24: Foobar for dummies tutorial.
updated 01-19: Koss KSC75 measurements with Kramer mod in headphones|measurements .
> added 01-18: Yello album reviews in music|album reviews section.
> added 01-15: Koss PortaPro measurements in the headphones|measurements section.
> added 01-12: Some information on the snubbering of diodes in rectifiers.
updated 01-03: the headphones|recommended ones section.
———————— 2014 ————————
updated 12-22: Changed the layout of the headphones|measurements section.
updated 12-17: How much power do you need ? answers in:  learn|power, impedance.
> added 12-11: How much power do you need ? answers in:  learn|power, impedance.
> added 12-08: AKG K551 modification article in the schematics|headphone section.
> added 12-05: AKG K551 and Beyerdynamic T50P measurements in headphones|measurements
updated 11-24: Superlux HD681-EVO article in the schematics|headphone section.
> added 11-14: Superlux HD681 replacement pad measurements in schematics|headphone
updated 11-06: Added some headphones to the filter PCB article.
updated 10-30: Some headphone cable measurements in the cable section.
> added 10-23: Teufel Aureol® Real in the headphones|measurements section.
updated 09-25: Superlux HD681-EVO newer version in the schematics|headphone section.
> added 09-18: SFI drivers DIY headphone in the headphones|measurements section.
> added 09-07: Superlux HD681-EVO modifications in the schematics|headphone section.
updated 08-30: Power amp adapter circuit added.
updated 08-25: Power supply article with additional info to repair SMPS
> added 08-21: Superlux HD681-EVO in the headphones|measurements section.
updated 08-15: Power supply article with additional info on mains transformers
updated 08-12: Power supply article with additional info on mains filters
> added 07-17: Plots of DT990-600 and KSC75  in headphones|measurements
> added 07-15: Some information about mains filters in the power supplies section
updated 07-14: changed the site navigation slightly.
updated 07-12: Jays V-Jays in the headphones|measurements section.
> added 07-11Silverscrest KH-2347 plots in the headphones|measurements section.
> added 07-02: HD25-1 / HD 320 / HD215, Philips SHP-9000 in headphones|measurements
> added 06-27: Sony MDR-XB500 plots in the headphones|measurements section
updated 06-30: Power supply article with additional drawings and info
> added 06-25: Vintage Stax SR-5 with SRD-6headphones|measurements
updated 06-23: Headphones section and added some pictures
> added 06-18: Information about amplifiers and how they work
updated 06-09: HD681 plots in the headphones|measurements section
> added 06-08: Simple rechargeable battery monitoring circuit schematic
> added 06-02: Review of Handel’s Messiah
> added 05-31: Review of Deep Purple’s album ‘Now What
> added 05-26: Anecdotal about a cable swap
> added 05-25: a link to an incredible amount of audio related online calculators and explanations
> added 05-23:Some information on different headphone driver types.
> added 05-18: Technical info about Project Starlight & Ember
> added 05-15: the HD681 revisited a new article about the filter and more background info
updated 05-12: the Headphone Correction Filter manual
> added 05-11: review of the band TinyFish in Rock/Pop reviews
> added 05-07: Review of Sennheiser RS160 – wireless headphones by Jeff.
> added 05-07: schematics of 2 new hybrid amplifiers.
> added 05-07: Some findings about DIY headphone measurement rigs.
updated 05-02: the Headphone Correction Filter manual and T40RP-mkII / T50RP manuals.
> added 04-28: information about the NEW Headphone Correction Filter circuit.
> added 04-14: review of the O2 headphone amplifier
updated 04-13: The new filter PCB a sneak preview
updated 04-10: Power supply article
> added 04-09: Measurements of a few headphones.
> added 04-05: part of the article on the usage of speaker amplifiers for driving headphones.
> added 04-03: Page with all headphone reviews on one page.
> added 04-02: headphone reviews
updated 03-31: Power supply article
> added 03-31: article about crossfeed.
> added 03-30: we added a FORUM in addition to the comment replies.
updated 03-29: Rock & Pop album reviews
> added 03-28: Some information about rectifiers in power supplies
2013-03-08: Website was created
———————— 2013————————