And now with a little PEQ (Below) showing a nice gentle roll off. This is in room, just the left speaker measured at the listening seat.
OB1 V1 @ Seat (Left) Smooth by Robert Seymour, on Flickr
And the PEQ function. Had the PEQ with more gain to make it even more linear but sounded a bit too dull and closed in, dialed it back a bit so the maximum +/- is 3dB with any one band.
V1 PEQ by Robert Seymour, on Flickr
Mmmmmm…graphs 
Little more tweaking but thought I would just post some speaker pron…
So part of my thoughts about getting a small lathe were also linking with getting ready with the big speaker project in the new year.
I have measured the 285GMF in my ~100 Litre test cabinet, with a lot of stuffing.
RED - Mic @ 500mm from driver, on axis and speaker in the middle of the room
BLUE - Mic @ 500mm from driver, on axis and speaker in corner of room
GREEN - Mic at Listening position, on axis and speaker in corner of room
285GMF in ~100Litre Closed Box by Robert Seymour, on Flickr
The suck out at ~350Hz is possibly related to the phase blip as shows up on the impedance trace, previously posted. Other than that, I don’t think it looks to bad for an 11" driver.
Seems to work well in terms of even bass response, and not peaking too much at 33Hz which is the big one in my room.
I would like to try it in a 2-way with a simple passive crossover (eventually) over to a tweeter, most likely a compression driver due to the required sensitivity.
Now, ages ago I had some of the Stereolab Tractrix horns but they seem difficult to find second hand, and the SEOS horns seem very expensive to get to the UK now so I thought, what about making a pair with a lathe, how hard could it be?! 
And I have a pair of these on their way…
I plan to start at around 2kHz and 1st order first, then try lowering it to ~1.6kHz 2nd order. These can easily do 800Hz 4th Order if needed although I would need a larger horn.
Initially I will be using the MiniDSP, although if I can, would like to go passive if the 1st or 2nd order crossover sounds good, and does not need to many notches/filters etc.
And a pair of these Faital Pro LTH102 to get me going before I sort out lathe faf…
Giant Mother Fucker?
I do hope so 
Could be!
I never really thought about it but I assume it may be “grave-médium-ferrite” as they are French, so Bass-Medium driver with a Ferite magnet rather than their AlNiCo or Field Coil motors.
Unfortunately there has been no progress, expected the Radian CDs on Friday but a delay with the delivery. PITA as I have a day off today which I had planned to make a start on the crossovers.
The FaitalPro Tractrix horns arrived last week though, very nice aluminium (cast?) build and loads of bracing:
FaitalPro LTH102 by Robert Seymour, on Flickr
On the MiniDSP with 4 slopes as a starting point as the presets so I can change on the fly:
6dB/Octave BW @ 2000Hz
12dB/Octave BW @ 1600Hz
24dB/OctaveBW @ 1200Hz
6dB/Octave Bessel @ 2000Hz
The Radian 475PB is happy with down to 800Hz @ 24dB/Octave aparently but the FaitalPro is only going to load down to around 1200Hz IIRC.
Radian 475PB drivers arrived!
Dont have the correct bolts 
Damn americans, just use an M6 bolt like everyone else!
Well, bit of a mix up, had a quick play with the Radians in, did not sound great at all in any of the first try, also far too much noise/hum. Still the same problem with the MiniDSP and an odd earth loop somewhere. Its not an issue when its not being used (with normal passive speakers).
So, a little disheartened, I had an idea, why not try the 165-2000 drivers in a smaller aperiodic enclosure (or resistive open backed) and use the 285GMF in a sealed box, and this is the result…
Supravox 285GMF/165-2000 Box by Robert Seymour, on Flickr
Rough cut out first of the old baffle and foam removed for the photo.
In place, with the horns not being used at the moment:
Supravox 285GMF/165-2000 Box by Robert Seymour, on Flickr
Bit of a play, and I have settled so far on BW 6dB/Octave crossover, with the 285GMF rolling off from 80Hz and the 165-2000 crossed at 300, makes for a smooth integration.
The 165-200 have a VERY flat impedance response in this configuration, from 4Ohms up to around 6Ohms at the peak (with a little flattening of the peak) at the Fb ~100Hz and then a rise up to 9Ohms at 20kHz. From previous experience, I should be able to smooth out the peak so its nice and rounded with a bit of tuning of the foam.
XO2 - Response by Robert Seymour, on Flickr
Thats with the drivers pretty much Naked, nothing on the bass and only a little -3dB dip at ~3kHz (PEQ/Q0.5 so very broad) to tame a bit of brightness.
And nice RT60 response with the existing room treatment
XO2 - RT60 by Robert Seymour, on Flickr
Well nothing has really happened in the past two weeks, had a persistant cold for a fortnight now so everything sounds like I’m wearing a pillow over my head.
Still getting hum, seems to be linked to the MiniDSP, and from some research online, there does seem to be form for issues with them, when it comes to hum. I think I shall investigate other options.
Down the plate amp route, the Hypex NCore units look great but getting a pair of FA123’s for example (100w/125w/125w DSP Board) is around £700 which is a bit steep at the moment.
Well, once again, a hop onto the roundabout, with suitable reason this time…
I decided to simplify the amount of stuff I had, seemed a bit OTT to have quite a bit of kit lying around, hence putting the Larsen 4.2, Rega R9 and Supravox bits up for sale.
We had planned to do our late honeymoon trip to Japan in November 2020 so I wanted to free up some cash so we could make it a bit more special, rather doing the trip on a budget.
In the past 2-3 months, we also decided that we should do something about moving house, a topic we had discussed quite a bit but not really started. We’re currently in a 3-Bed Semi, with the 3rd bedroom taken up by our pet Tortoise! Now, we have a rough plan to start a family in the next year or so and it would quite quickly become quite a cramed house, even with a workshop & utility room on the side.
We put our house up for sale just over a week ago, and wanting to make the living room a lot more attractive, moved the various speakers into store or sold, and went with a compact system on top of the Ikea LP storage.
Temp system V1, with some Spendor S3/5Rs taken in swap for the Larsen 4.2.
System by Robert Seymour, on Flickr
I had heard the S3/5Rs before, back when I was working in the hifi shop, and the fitted the bill for some small, sealed speakers that would work close to the wall until I could find a pair of small ATCs. They are OK, pretty much as I found before, very smooth and ‘nice’ but lacking any dynamics and bass is a bit soft.
And V2 with the ATC SCM10s that I managed to source! Much more up my street, superb resolution and actually a bit too much space when used in this position. Supprising bass depth compared to the S3/5Rs given its a similar sealed box design.
Just need to source a pair of stands now, I fancy another pair of Target R4s although I would like to try something like the Something Solid ones to match the Rack I have.
System by Robert Seymour, on Flickr
Now since then, we have had an offer accepted on ours, and had our offer accepted on the new house, a 4-bed detached property, that will allow us to have a dedicated hifi & sewing room (for Mrs Hoops).
Although the room is not massive, its similar size to our current living room (~17ft x 11ft) so the ATCs should be ideal. It also has a large extension with a 23ft ‘Family Room’ which we will likely use as a general living room with the TV and probably some fun Home Cinema kit*, which will be nice!
So all change
*Just to add, the Radian 475PB/horns, MiniDSP have not sold, so I may end up keeping and making something horny for the Home Cinema for the big room (or some big tannoys)… 
Stating the obvious, but in terms of noise (yours and other people’s) that’s worth its weight in gold.
VB
Terrific post Rob, I really hope it all works out for you.
Real life and hifi in parallel!
yeah, its a should be bit of a step change going from previous shared houses, maisonette and semi-detached.
It has plenty of off-street parking too, and while we have no kids, plenty of spare rooms so a moving bake-off in the summer will certainly be on the cards!
Are you sure. Mistakes have been made before 
Not sure I understand… 
Let’s just say that there are people (well, a person) in this forum who bought a house seemingly not knowing very much about it 
