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Denon 3805 + KEF THX TDM setup with Velodyne


Established Member
A few quick questions about setup....

[[Samsung 50" plasma -> Denon 3805 -> KEF THX Tdm 23c\23f\34ds + Velodyne VA-80]]

Just got round to reversing the slug on the fronts and recalibrating and its sound miles better than yesterday!

1) The Diapoles (34ds) are actually labelled right and left on the stickers... although ive moved them now, are they configured any differently from each other at the factory? if you were to use the left hand surround for the right side etc?

2) Dont know what to do about the center volume channel, feels like the 23c is holding back on me for some reasen, the denon calibration has set the speakers as:

FL = +2db
FR = +2.5db
C = +2db
SL = +5db
SR = +5.5db
Sub= -5.5db

Subwoofer = LFE (didnt quite understand what LFE + MAIN was!)
Crossover = 80hz
All speakers set set to LARGE
EQ = Flat (although tried, Normal and off to no real advantage.)
Tone = OFF

Any ideas people?

Is it common to have to add more db to the center channel to get a more balanced out sound at lower volumes... Dont get me wrong it sounds awesome at 0db but -35db and its all effect and no center! :)

3) Does anyone have any good settings to start with for the Velodyne VA-10x.... Volume, Crossover etc...

Any info would be awesome guys!


Prominent Member
Seems to be the concensus you'd be better served setting all your speakers to small regardless of how big you think they are. The theory being that even large speakers won't handle the LFE as well as your sub, which after all in designed with just that in mind.

I also have a 3805 and have my Xover set to 80 and all speakers to small.


Distinguished Member
KEF TDM's roll off at 80Hz in a way that compliments a THX receiever's 80Hz crossover. They should absolutely be set to small with a crossover of 80Hz. That's how they were designed.

I used to have a set and I miss them terribly. Fantastic speakers.

On the rear L&R channels, the TDM34DS should be positioned as indicated by the serial number suffix i.e. L or R. This is so the front firing driver is in phase with the front speakers.

However, if you use the TDM34DS on the back channels in a 7.1 system then their position MUST be reversed... I.e the left speaker on the right and vice versa. If you don't reverse them in this position then the drivers facing each other will be out of phase and cancel each other out.

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