You are probably looking after the: spinorama gallery.
It is a collection of loudspeakers measurements. They can
help you to make an educated decision when you want to purchase a
speaker. Price and quality are very loosely related. I do not have
specific recommendations but I would buy for myself:
For a bookshelves or desk speaker:
Floorstanders or large speaker:
- In the US, I would likely buy a pair of Revel.
- In Europe, I baught larger Genelec (8361).
The website is generated from this
code. Most of the
speakers data are from
audiosciencereview.com aka ASR, Princeton 3d3a
Lab and some vendors.
Shape Optimisation project (for speakers)
I used to to some shape optimisation long time ago for my PhD. This post motivated me to go back to it.
Comsol or Mathematica are too expensive for my taste esp. with a lot of cores. I decided to leverage awesome open source softwares and write an open source project to optimise horns to start with.
- (2021-07-23) More reading: how to precondition Helmhotz? also read about other optimisation (matric reduction and parametrisation)
- (2021-07-22) More reading: read the fireshape documentation and code, also had a peak at ROM.
- (2021-07-20) Same code is working in parallel. 2D is super fast on a core i9 9900K and 3D is slow but doable. Memory and memory bandwidth are an issue. It also works well on Threadripper pro, memory issues are gone.
- (2021-07-20) Did a lot of reading.
- Code is now working to solve the state problem (Helmhotz) in 2D. I used features from my other project to generate spinorama and contour plots.
- (2021-06-05) That’s me trying to remember things from the past.
- Code is here.
- I am following the tutorial from Mathematica but I implement it in Python with open source solutions (gmsh and firedrake).
- Here is the mesh for a half horn (due to the symmetry the problem is computed in 2D and only half of it).
- If I can solve it properly I will of course go 3D.
- (2022-05-26) Debug target again and try to decrease preamp changes.
- (2022-05-05) Corrected the rear reflections which are incorrect in the standard
- (2021-09-06) Added a second optimisation algorithm that gives better results :)
- (2021-04-10) Investigated how to find a target (or set of targets) that maximize the score. Use ray[tune] and random grid to find automatically optimum targets. That’s different than for a given target, find the optimal EQ.
- (2021-01-30) Investigated why some speakers don’t eq well. Not sure about the answer yet but mostly:
- the target is critical and the system is not smart enough to guess it correctly each time.
- zones where the crossovers or port resonance are generating large non linearity should be ignored.
- (2021-01-17) Build a script that compute all EQs :)
- Results are in text files called iir-autoeq.txt (compatible with Equalizer APO).
- The script around the algorithm has a fair number of knobs to play with.
- (2021-01-13) Found a working algorithm that generates EQ as good as made by hand :)
- Greedy algorithm
- Use simmulated annealing at each steps
- Optimise for flat LW and smooth PIR
- 2 min per speaker max on 1 core
- 14 min for all eqs on all cores
- Now things are easy :)
- (2021-01-09) Added local optimization with a gradient to see if I can get a better optimum.
- answer is surprising and is NO.
- I don’t understand why yet.
- (2021-01-02) Optimised Listening Window with a series of PEQ. Tried various strategies:
- Greedy algorithm: start with the highest peak and optimised for this one. Iterate.
- Greedy algorithm: start with the highest area and optimised for this one. Iterate.
- Optimise for L2 norm or optimised for R**2 (from linear regression on LW)
- Same as above with a constraint on On Axis (need to stay flat)
- (2021-04-10) added some featues
- added links to original reviews and others if I have them
- added horizontal and vertical views for coaxial speakers that you can return and a few others like Focal Twin6 Be.
- (2021-04-01) added some features
- Compute directivity in degree such that it minimize the difference between -6dB and a flat line over a frequency range. That make it less random that doing it by hand and it generates significantly different results.
Working in slices of 20 minutes
I have always been good at focusing on 1 thing for hours. Since this projects are personal and not work related, I do not have much time and when I have that’s always in very short slices of time.
I devised a methodology to work like that and if it requires rigor it is working pretty well. It is very frustrating way to work but I have made progress.
server board Asus WRX80 (2022-05-05)
- Before upgrading BIOS
- Put the CAP file from ASUS in /boot/efi/EFI/ASUS
- After upgrading BIOS
- U2.1 and U2.2 needs to be SATA and not PCI-E
- 6th PCI is RAID and not 16x (that’s the one with 4x NVNE)
- ZFS is amazing! Lost 2 disks today luckily under guarantee.
mac M1 (2022-05-05)
server board Asus WRX80 (2021-08-17)
- Finding a case
- I have a BeQuiet 900 rev2 which claims to be able to host a E-ATX motherboard. That may be true but then you need to remove the hardrives … The motherboard is 30cm x 33cm and the mini-SAS controller use another 8 cm.
- Finding a large case is a challenge: either they are not build anymore or they are very expensive or they are not available.
- Went for Thermaltake Core W200
- Issues with thermals (Processor is 280W, GPU is 350W …)
- Lots of 3k fan fixed it.
- The SP3 cooler from Noctua is working well but it is not aligned with the natural air-flow and I will need to change it one day. The supermicro cooler should work better but is far more noisy.
- Good that the server is in the basement.
- Issues with SATA controllers
- It took me awhile to understand that the second sata controller is broken on this motherboard. I had to isolate disks one by one and test them 2 with 2 differents cables on 2 different controllers to be sure it was the controller.
- I added a cheap HP HBA controller (working)
- I also used the 2xU2 ports with a mini SAS to SATA cable (working too and much faster)
- Over the two 4 ports sata controller, 3 are working in the first one, 1 is working on the second one.
- I will need to send the card for an exchange and that will be a PITA.
- How to set the fan speed
- via IPMI of course
ipmitool -I lanplus -H 192.168.1.114 -U admin -a shell
# noctua 15' on the cooler
sensor thresh CPU_FAN lower 0 100 200
sensor thresh CPU_FAN upper 1700 1800 1900
sensor thresh CPU_OPT lower 0 100 200
sensor thresh CPU_OPT upper 1700 1800 1900
# noctua 3k
sensor thresh CHA_FAN1 lower 0 100 200
sensor thresh CHA_FAN6 lower 0 100 200
sensor thresh CHA_FAN5 lower 0 100 200
sensor thresh CHA_FAN1 upper 3300 3600 3900
sensor thresh CHA_FAN6 upper 3300 3600 3900
sensor thresh CHA_FAN5 upper 3300 3600 3900
# top fan
sensor thresh CHA_FAN2 lower 0 100 200
sensor thresh CHA_FAN3 lower 0 100 200
sensor thresh CHA_FAN2 upper 2000 2200 2400
sensor thresh CHA_FAN3 upper 2000 2200 2400
# disk fan
sensor thresh CHA_FAN4 lower 0 100 200
sensor thresh CHA_FAN4 upper 2000 2200 2400
# soc fan (build in the motherboard)
sensor thresh SOC_FAN lower 0 100 200
sensor thresh SOC_FAN upper 3300 3600 3900
sensor thresh CHIPSET_FAN lower 0 100 200
sensor thresh CHIPSET_FAN upper 3300 3600 3900
- Issue with IPMI web interface
- Easy case: certificate are not correct and you need to use Firefox to connect and then change them.
- Change in BIOS for reference
- PCI_6: 16 -> 4x4 for NVME
- U2: -> PCI -> SATA
- HP HBA controller
- Need to put in non-raid mode …
macOS 11.2 fix most of my issues but not all (2021-02-10)
The mac mini is still slow and it make it impossible to use with Reaper and a few plugins. Logic is working better but still not great.
Seriously unhappy with my imac M1 (2020-12-26)
My new imac crash once or twice a day, becomes unresponsive etc. That’s kernel crashes. I hope Apple will fix most of them in next version of Big Sur.
Fixing xcodebuild (2020-12-26)
On a new mac I never remember how to install xcode and command
line. I ended up with an errorw which
sudo xcode-select -s /Applications/Xcode.app/Contents/Developer
sudo xcodebuild -license accept
Markdown development (2020-12-26)
- Discovered grip server to preview markdown files
- Installed markdown-mode and grip-mode for Emacs
Nice trick to cleanup a git repo and keeping only the last commit (2020-12-21)
How to make a bootable windows usb key (2020-12-21)
- Partition a usb key with cfdisk or similar
- One partition EFI and another with at least 8GB fat with GPT partionning
- mkfs.fat /dev/sdX2
- mount /dev/sdX2 /mnt/usbkey
- Copy the ISO files to the the second partition
- sudo mount Win*.iso /mnt/cdrom
- One file is larger than 4GB and of course doesn’t fit on FAT
- https://wimlib.net/downloads/ to the rescue
- rsync -avh –progress –exclude=sources/install.wim /mnt/cdrom /mnt/usbkey
- wimlib-imagex split /mnt/cdrom/sources/install.wim /mnt/usbkey/sources/install.swm 3800
- eject done
- BIOS : remove secure boot and put Other OS instead of Windows since the above is not UEFI compliant.
Installing ray on Big Sur on a ARM mac mini (2020-12-21)
- Not fun
- Redis need a patch or crash at the start
- python3.8 is ok but 3.9 is not (?)
- Install ray from source did work
Roon is no fun (2020-12-21)
- Updated my roon core
- Roon restarted nicely from backup
- RoonRemote is working on various devices but not on Mac Mini M1 (doesn’t see any audio device)
- How to firewall roon on Linux from this article:
- opening a few ports is not enough:
sudo ufw allow from 192.168.1.0/24 to any port 9100:9200 proto tcp
sudo ufw allow from 192.168.1.0/24 to any port 9003 proto udp
sudo ufw allow from 192.168.1.0/24 to any port 1900 proto udp
- you also need to enable broadcast and IGMP
### IGMP ###
-A ufw-user-input -s 188.8.131.52/4 -j ACCEPT
-A ufw-user-input -d 184.108.40.206/4 -j ACCEPT
-A ufw-user-input -s 240.0.0.0/5 -j ACCEPT
-A ufw-user-input -m pkttype --pkt-type multicast -j ACCEPT
-A ufw-user-input -m pkttype --pkt-type broadcast -j ACCEPT