I recently spent the day at Sennheiser UK headquarters listening to some of their KH80 DSP monitors both in stereo and as part of a multichannel install. Spoiler alert. If you’re looking for some small high quality monitors then you owe it to yourself to check these out. Read on to find out why…
The KH 80 DSP
The first thing which will probably strike you when seeing these monitors for the first time is just how small they are. With a 4” bass/mid driver and a tweeter set back in a large waveguide in a compact, front ported plastic moulded cabinet they are really tiny. In truth this did colour my expectations and looking at the specs the first thing I looked for was the frequency response. They actually put out a surprisingly deep 57Hz (-3dB). This made me wonder whether they would be over ported and suffer the timing problems of bass overhang and potential “one note bass” which can happen when people try to get too much bass from too small a cabinet. I didn’t have to worry as the bass, though light - if you want to hear whats happening in the bottom octave you’ll need something like a KH 805 subwoofer, in which case you’ll be good to 18Hz. That would be a nice compact monitoring setup.
So what bass these things put out is at least well behaved. One of the most striking elements of the KH 80 DSP is the large waveguide surrounding the tweeter which looks very similar to the one on my KH 310s. This waveguide promises smoother off axis performance which as well as promising a wider sweet spot is also important because of the contribution reflected sound has on the listening experience. Off axis sound reflected back by the walls of the listening room which differs significantly from the on axis direct sound makes a lot of difference to how forgiving a speaker seems to be of less than ideal acoustics in a room. This waveguide also shapes the wavefront giving a wider horizontal dispersion and a narrower vertical dispersion.
Connection and Controls
On the back we find a combi XLR/Jack socket for analogue audio input, a fig 8 AC power inlet and associated rocker switch, an RJ45 network socket for network control via the Neumann Control software and some threaded brass mounting points.
In terms of controls we have an analogue input trim and output trim controls, So far so normal then. The DSP then introduces extra functionality ranging from quick and easy through to thorough and sophisticated. The really important part is that it is up to you how deep you want to go in setting up this DSP.
KH 80 DSP - Back Panel Switches
Basic speaker correction can be carried out from the back panel, a 4 position Low Mid Acoustical Control offers correction for issues introduced by placing the monitor on a flat surface. Depending on the specific configuration of the speaker and the desk on which it is placed, there will be a prominent contribution made by the first reflection of sound bouncing off the table and reaching the ears, which when combined with the direct sound from the speakers causes issues in the lower midrange. Because the geometry of this first reflection is reasonably predictable, presets can be built into the DSP and are made available from a 4 way switch. The four choices offered are: Free Standing, Small Desk, Medium Desk and Large Desk.
Neumann Control App
If the local/network control switch is set to Network then the possibility of much more detailed control of the DSP becomes possible. I heard what can be achieved using the control software setting up a multichannel install when I heard some live recordings played back over a 9 channel Auro 3D install. The sound was effortless in a relatively small install like this with bass management via a KH 810 subwoofer. The only justification for running larger speakers would be in a larger room where more headroom would be required due to the increased distances but when used within their operating specs these are very capable monitors.
In the stereo set up I was auditioning the monitors which were set up on a small table. There was a noticeable thickness through the midrange which I felt needed fixing. This wasn’t unexpected as the KH 80 DSPs were placed directly on the table. Changing the Low Mid Acoustical Control to small desk immediately lightened things up in the lower mids but I felt things could be further improved.
Changing to Network Control and connecting to a router I was able to access the DSP built in to the KH 80 DSP via Neumann’s Control App. This App provides access to 8 filters per speaker, time alignment delay settings as well as systemwide high and low shelf EQ and level control. The App doesn’t offer any way to make a measurement, it instead offers the tools to set up your monitors whether you have the means to take a measurement or not. If we take settings for the Low Mid Acoustical Control on the back to be level 1, the app offers levels 2 and 3.
Level 2 - Guided Setup Using the Neumann Control App
The App can take a best guess at the appropriate correction settings in response to some questions about your room. It asks about things like the room dimensions, the listening position and the acoustic character. From this the software makes more detailed adjustments to the corrective curve. Using this method a much improved sound was achieved, with the -2db cut at 400Hz and associated tweaks taking a sound which was best described as fair but lumpy to something considerably better. This is a great approach as it takes into account that many people don’t have a measurement mic and aren’t going to get one. This approach offers a best guess but if you do have a measurement mic you can go a stage further.
Level 3 - Detailed Setup Using Data From A Measurement
If you have the means to take measurements of your room then using the App you can manually match the curve using the 8 filters available. Given the flexibility of a digital filter these are enough to get close to any imaginable shape. In my case I’d probably use Fuzzmeasure to take and averaged measurement, though this is a paid for product. I’ve heard that Room EQ Wizard is free and very good, though I’ve never used it so I can’t personally recommend it. This is only looking at the use of the filters in a single speaker but there are options for time alignment and multichannel system control too.
The Sound Of The KH 80 DSP
So how do they sound? To sum it up in a word I’d go with impressive. These retail at around $500 each and are absolutely tiny. If you can live without deep bass (and many people can) and you intend to use them in a nearfield application these monitors have all the level and resolution you need. Add a sub and you’ve got some proper monitoring for a project studio.
The sound is surprisingly grown up. Possibly because of the small bass driver the midrange performance is very good for a 2 way design. I’d brought my 20 year old Genelec 1029a’s as a reference and the Genelecs sounded positively scooped by comparison. I think these would be an excellent choice for someone working on dialogue because of this very together midrange performance. This midrange performance got me wondering about the crossover and it turns out that they crossover at a not untypical 1.8KHz but the crossover filters are linear phase 48dB/Oct filters. The mention of phase correction got me looking for latency figures as linear phase filters always affect latency. It appears that the monitors can be run in a low latency mode where latency is down at 0.65ms and in linear mode it is 2ms.
The real strength of these monitors that due to the network control and correction, combined with their small size, hardware mounting options and reasonable cost per unit they make an excellent choice for multichannel installs and with the increased interest in Dolby Atmos these rugged little speakers might well find a natural home.