A person with a transit van. That’s how I moved a couple of key items of furnishings, some fundamental filming gear, a number of safety cameras and chosen hi-fi parts from Berlin to Lisbon in very early January. (I used to be to greet its arrival two days after it left however my proper eye delayed my outbound flight by three weeks). With van area at a premium, I needed to be picky. And rapidly. The Zu Soul 6 have been a non-negotiable as I used to be near-certain that their deep crimson gloss end would look tremendous good as soon as set down on the Lisbon house’s black and white tiled ground. I used to be not mistaken. That huge field selection then meant that the remainder must be smaller items: KEF LSX II + stands, Sonus faber Lumina II, Technics SL-1210GR, Buchardt A500, Meze 109 Professional, Rosson RAD-0, Chord Hugo 2 + 2go, RME ADI-2 DAC FS, iFi Zen Streamer and Enleum AMP-23R. Unwittingly, I had put collectively a group of Kallax-Fi for its new life in Portugal.
With the world’s hottest vinyl storage system on my thoughts, I additionally had to decide on which room correction-capable amplifier would make the 3000km street journey southwest: the Lyngdorf TDAI-1120 with Room Good or the NAD M10 V2 with Dirac Dwell? RoomPerfect makes lighter work of pulling a subwoofer into the room-corrected body however the NAD has a big color show and delivers a fatter, punchier sound to make it higher suited to a broader vary of loudspeakers. Moreover, already realizing that two subwoofers from GoldedEar have been about to come back down the pike, the Canadian shoebox amplifier received the nod.
In a current publish, we established that the midrange and high-frequency reverb time (RT60), as measured on the listening place in my 4m x 7m Lisbon listening room, clocks in at a mean of 1 second. That quantity of reverb, clearly audible in each hand clap and voice recording assessments, is way larger than the quantity advisable by acoustic professionals: between 0.3 seconds and 0.7 seconds from 300Hz to 4kHz.
And while we didn’t utterly disprove the acoustic utility of a rug in that earlier publish, we poured chilly water on the audiophile neighborhood considering that conflates the addition of a rug (and diverse heavy furnishings) with correct room therapy. Your grandfather’s Winchester is just not a bass lure and his footstool is just not a Helmholtz resonator.
An honest-sounding room is an important software for anybody professionally assessing high-performance audio gear. For yours actually, it goes additional nonetheless. Having lived with an entire Vicoustic fit-out for the previous 18 months in Berlin, I knew earlier than flying out to Lisbon that I couldn’t go with out within the new place. Having since measured the room’s RT60 within the seat, I’m glad I took the time to tee up the room’s skilled therapy earlier than I left Germany.
In every other nation, I’d have appeared to a different acoustic panel producer in order to not not play favourites. However Vicoustic is a Portuguese firm, its headquarters a mere 20-minute drive from my new dwelling. I despatched them the architectural plans of my Lisbon house plus the specifics of the wall supplies (plasterboard fronting masonry) and the ground (tiled). The non-parallel entrance and rear partitions would apparently work acoustically in my favour. Two weeks later I had a proposal doc containing 3D renders of the room’s deliberate fit-out, as seen from a number of angles. Set up day was booked for 2 weeks after wheels down.
Shifting in, sorting an Web connection, quite a few buying journeys for the naked necessities and my failed rug take a look at (and its two accompanying movies) ate a complete week. That left solely a two-day window for me to research what room correction software program from Buchardt and Dirac (by way of NAD) might do – if something – for the room’s overly lengthy reverb time.
Per attitudes in direction of rugs and sofas, some corners of the audiophile neighborhood had room correction software program pegged as a one-for-one substitute for skilled acoustic therapy; a software program stand-in for when the aesthetic make-up of a room can’t be messed with. Might the facility of DSP actually enable the hifi-loving minimalist or ‘WAF’-wielding boomer (😉) to have his cake and eat it?
The Buchardt A500’s accompanying Platin Hub asks us to wave an iPhone across the room, overlaying corners and partitions, as its microphone reads 90 seconds of take a look at sign pushed to the Danish standmounts over a low-latency WISA connection. The smartphone app then analyses the iPhone’s studying to supply up a corrected output curve for the loudspeakers that will, in idea, optimise their in-room efficiency.
I did this then I put a UMIK-1 measurement microphone on the listening place and linked it by way of USB to an M1 MacBook Professional working Room EQ Wizard (REW) which in flip was USB-connected to the Platin hub. The room correction (RC) curve may very well be turned on and off with a single click on (contained in the app) to make gentle work of taking an RT60 measurement with the room correction off after which on:
To higher perceive one main purpose why the Platin hub’s room correction software program makes zero distinction to the RT60 (between 300Hz and 4kHz), we should take a look at the frequency response (FR) graph the place we word an uplift within the decrease frequencies. The room correction software program desires the A500 to push extra low-end into the room however that’s not our focus right here.
What’s then? Have a look at the place the strains start to diverge. The Buchardt/Platin room correction software program targets solely frequencies beneath 350Hz. An electronic mail to Mads Buchardt confirmed as a lot. That the next smartphone app screenshot exhibits one thing severely amiss with the room correcting app’s frequency response evaluation of my room – later decided to be a defective Platin hub – makes not a jot of distinction to in the present day’s findings. The takeaway right here is that the Buchardt/Platin room correction system targets solely bass and modifications nothing above 350Hz: not the frequency response and particularly not the RT60.
The LE model of Dirac Dwell that ships with the NAD M10 V2 suffers an analogous destiny. It’s hard-curtained at 500Hz to make its correction a bass-only deal. A one-time fee of $99 drops the LE and its 500Hz curtain to provide us full frequency response correction (20Hz to 20kHz) and an editable correction curve. I upgraded some years again so up subsequent was a cellphone name to skilled Dirac Dwell installer Terry Ellis to make sure that no errors would creep into the Dirac Dwell measurement course of. The loudspeakers being pushed by the NAD built-in have been the Zu Soul 6.
Just like the Buchardt room correction system, Dirac takes information from a number of microphone positions. Our 5 UMIK 1 microphone measurements netted the next frequency response and a default correction curve – the straight line that runs by way of it – that we elected to not edit earlier than pushing it over the air to the NAD M10 V2.
With REW again within the driving seat, right here we see the in-room response of the Zu Soul 6 frequency response measurements with Dirac Dwell on and off. Discover how Dirac Dwell has smoothed the Zu’s in-room response. Good! What this measurement doesn’t seize is how Dirac Dwell nudges the phantom centre picture into (higher) focus. Zu’s Sean Casey would in all probability choose I name this ‘superior stereophony’.
And but the room’s lengthy reverb tail stays audible. That rubber meets the street after we take a look at the midrange and treble’s RT60 with Dirac Dwell on and off. The NAD’s room correction smarts fail to enhance the reverb occasions of frequencies above 600Hz and barely worsen ’em beneath that time:
Can room correction software program enhance the ‘sound’ of a listening room? Sure. But additionally no. Software program like Dirac Dwell clearly controls the loudspeaker’s output – we will hear it and we see it in REW’s frequency response graphs. And from the restricted quantity I perceive, it might probably heal a while area points – albeit to a lesser extent.
Nevertheless, room correction software program seems to have next-to-no management over sounds which have already left the loudspeaker to snooker across the room. How might we fairly anticipate anything?
Our conclusion for in the present day: nothing that I’ve measured right here with REW – and nothing that I’ve heard throughout music playback – means that room correction software program can meaningfully enhance an extended room reverb time within the all-important area between 300Hz and 4kHz.
Which means all of the heavy lifting now falls to Vicoustic…