For remarks, discussions, questions, about this website or to contact us please visit our FORUM.
When new information is added it will be shown below in the ‘whats new‘ section below.
Working on a in-line filter board that can be connected between a source and any headphone amp.
Prototype is built and ready for testing (on the left the PCB, on the right completed device)
What’s new ?
> added 08-06: Influence of Fletcher-Munson on listening pleasure in tutorials
> 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 tutorials|articles
> added 06-01: Beyerdynamic DT150 measurements in measurements|Beyerdynamic
updated 05-26: Headphone adapter article in Tutorials|Power-amp-adapter
updated 05-21: Superlux HD662-EVO measurements in measurements|brand Superlux
updated 05-14: info about SMPS vs LPS power supplies in tutorials|power supply types
>added 05-04: Ausdom ANC7 measurements in measurements|brands A
>added 04-15: Schematic G1217 project Ember rev. 2.1 in schematics|amplifier
updated 03-09 AudioQuest NightHawk cable in measurements|brands A
>added 03-03: AudioQuest NightHawk measurements in measurements|brands A
> 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|brand Superlux
> added 01-28: HiFiMan HE-400i measurements in measurements|brands G-O
> added 01-24: Beats Studio Wireless measurements in measurements|brands Be-F
updated 01-24: Ausdom M05 measurements in measurements|brands A
> 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|brands Be-F
> added 12-19: Bravo Ocean modifications in schematics|amplifiers
> added 12-16: Kameleon-2 article.
updated 12-13: Philips cityscape uptown in measurements|brand Philips
updated 12-02: Superlux HD681 and HD681-EVO in measurements|brand Superlux
> added 12-02: Superlux HD572-SP measurements in measurements|brand 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 explanations|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 explanations|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 explanations|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 explanations|power supply/filters
> added 01-21: ARTA setup guide by BMF in explanations|articles
> added 01-20: my views on ‘burn-in‘ in explanations|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 explanations|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 Explanations|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: Explanations|power, impedance.
> added 12-11: How much power do you need ? answers in: Explanations|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 inheadphones|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 07-11: Silverscrest 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