Recent content by solderdude

Below HD550 vs HD650 (= HD6XX) with acoustic smoothing applied. HD550 has less warmth (more neutral) and is better extended. Also less forward/clear (1-5kHz) and a bit more sparkle (8-15kHz)

This points to a grounding issue. A loop through the chassis and signal ground wires. Possibly because of 2 devices being connected to ground at differeny points on the chassis. The 'noise' signal on the output of the amp is probably the RF of the class-D operation of the output stage and the...

It can only do so when it is an op-amp that is not suited for the job or is oscillating. One can perceive a change in sound when changing (suitable) op-amps but this is not caused by the op-amp themselves but is caused by the whimsical nature of 'human perception'.

The mediafire link should still be O.K. as I can update that link. There was an error in the PDF so the more permanent link for the fixed pdf to my website is now : https://diyaudioheaven.wordpress.com/wp-content/uploads/2025/07/headphone-power-table-2025-1.pdf I can't edit my posts here after...

Some Focal headphones clip 'hard' in one direction. It sounds awful and consists of loud 'pock' sounds, 'rattling'. This is where the driver hits a physical excursion limiter. No idea if that is intentional (could be given the design) or that it just has to do with how it is made. Most...

conversion from 'xV to produce 94dB' into dB/V = ((20 x (LOG(10) (1/voltage))) + 94)

If it weren't for the clamping force I would have a hard time telling them apart other than the HD550 having a bit more 'sparkle'. If one already has a HD560S I see little reason to buy a HD550. When one does not have a HD560S and is torn between HD550 and HD560S and don't mind paying double...

Nice. What could be handy is a converter for dB/mW and dB/V for headphones.... including one that lets you convert 'needed voltage to reach 94dB' into dB/V.

On the other hand... One of the first things* to fail in a device with an internal (SMPS) power supply usually is ... the power supply. External = easy to replace. (*maybe except for volume control potmeters and signal relays)

Distortion and frequency response is solely determined by the output stage that comes after the input op-amp buffer stage. The performance of as good as any op-amp (with the exception of a few totally NOT suited op-amps) is vastly superior of that of the output stage. So ... in all cases you...

Does the volume control work from the pre-out ?

RETURN the SP3000 it is not well suited to drive low impedance headphones. Also I am not going to check all DAPs for technical performance.

It will ONLY supply 6V in high impedance headphones. The output stage simply can not supply current. Measurements in 32ohm were made by Cameron. Ah... so ergonomics/operational and not technical performance.... sidegrades technically, upgrades in features/looks/operation/size/battery...

If you like more sparkle use the EQ... 1015mW vs 900mW is just 1.3dB louder... hardly noticeable. WHY do you so desperately want to replace the M7 ? Why do you think something else is going to be an 'upgrade' ? What do you look for in an 'upgrade' ? What aspect(s) do you want to be 'improved' ?

open ? closed ? portable usage ? connected to what gear ? The only wired over-ear headphone Sony sells in that price range is the MDR-7506 which is a decent studio headphone but not suited (IMHO) for music enjoyment unless you have small ears that are flat against your head and like sharp treble.