Thanks Burkhard.
I do not believe that the vintage chorus acts like the effects outlined in the section of the manual you directed me to.
No matter what I do the rate will not display in musical values.
Again. I am looking for exactly how one relates the 0-10 (the range of the rate selector) to a duration (either seconds / milli-seconds or musical values in relation to the current tempo.
When recording I utilize my Kemper with no effects (Delay, Reverb, Chorus, Flanger,..) and normally add them to the track. I do this in case I ever want to change the tempo of a project.
I have decided that I am NEVER going to change the tempo of a projects ever again (as it is a PIA)!
On the Kemper Vintage Chorus, what exactly is the resolution of the 'Rate'?
Say for instance I have a profile at 162Bpm. Is the 'Rate' related to the Bpm in some fashion.
Say I have tap enabled and I tap at 13Bpm. Does the 'Rate' change?
Finally, what is the resolution of the rate?
I understand milli-seconds, seconds, note durations (1/16. 1/8, 1/4...), but I do not understand 1.5, 2.5 3.5 (values of the rate chicken knob).
Yes I could 'tweak it to taste' but I do not trust my ears!
Thanks in advance.
Woke up this morning with a clear head (un-cluttered by Thiele / Small, cubic volumes,...) and realized my answer to the additional volume created by the usage of a forstner bit and T-nuts is of course bondo (automobile body repair material)! I will simply fill in the gaps created with bondo and then sand it smooth (wood filler will not stick to metal, Bondo will stick to both metal and wood).
Dooo!
Dr. Decibel replies that the position of the speaker and port is not relevant within the design (i.e. it has nothing to do with Thiele / Small). He says they both can be positioned anywhere as long as neither of them end up touching anything (sides, each other). So I am repositioning both the port and speaker within the baffle to give myself ~7/8" thickness for the grill frame on the top and bottom of the speaker. I feel this is much better (stronger) than the ~3/8" defined by the design.
semguigui
I am extending the top, bottom and sides to extend out from the baffle (overhang) by 1 3/4" (not the 18mm specified). I am going to utilize SJ3463's to attach the grill frame to the baffle. These are by far superior to normal Velcro strips. The 1 3/4" gives me the clearance for the engagement thickness of the SJ3463's, semguigui's 2mm for staples and grill cloth thickness. This also allows me to be a little sloppy on the grill frame dimensions (undersize it slightly to make sure!).
semguigui:
'guigui'? You a programmer?
BobWalter,
Thanks Bob. I am aware of form-a-gasket and it is my go to if I cannot find any other suitable gasket material. I am also aware that I could simply purchase a sheet of gasket material and cut my own. It would be nice though if speaker supply houses had a 1/16" thick, sort of soft, 12" gasket available! Plenty of 6.5" and 8" such animals available, but no 12".
All (Just some babble for general readers) :
Note: I am a very anal programmer. I will now put my anal tendencies on display for all.
I am envious of all of you non state-side individuals whom have wood working tools and tape measures allowing you to cut on mm's! Metric->imperial measurements never work out. I have re-sized the design so I have cut lines on 1/8" and 1/16" inch marks. This has of course changes the interior volume of the cabinet (has made it larger). I am making up for this by re-sizing the battens (treated as bricks in speaker designer terms) so they take up more volume.
It is my understanding from my reading of Thiele / Small that this is all really about the volume of free air contained within the cabinet along with the amount of air pressure created by the movement of the cone (flexing in and out). The circumference and length of the port provides a sort of throttling effect that provides 'back pressure' against the back of the cone at a certain pressure to keep it in equilibrium. So I believe that the slight resizing of my cabinet and matching the volume of my bricks to make up the difference does not effect the performance of the cabinet.
Anal:
I am utilizing T-nuts and machine screws to connect a pair of handles, four feet and the 8 machines screws that hold the speaker to the baffle. It took me several days to decide whether or not I should utilize a forstner bit to 'sink' the T-nuts into the plywood so they are flush, or to simply drive them in. If I drove them in then the surface of them would be sticking up above the surface of the plywood which would decrease the interior volume by roughly the circumference of the T-nut head * the thickness of the T-nut head. I say roughly due to the fact that a T-nut head is not a perfect circle as it has 'wings' on it. To minimize this I decided to utilize a forstner bit to the depth of the thickness of the T-nut head. This of course is still not perfect as the circumference of the forstner bit is a bit larger than the circumference of the T-nut head, and I still have the 'wings' issue. Utilizing the forstner bit increases the internal volume of air within the cabinet! This keeps me awake at night!
I have thought I could get a finely graduated cylinder, fill it with liquid and then dip the T-nut into the liquid up until the bottom of the head. The difference in the level of the liquid would be the volume displaced by the head of the T-nut. I could then find the volume of my forstner 'indentation' and subtract the volume of the T-nut head from it. This would be the internal volume added to the cabinet by the presence of the T-nut. One would of course need to know the evaporation rate of the liquid chosen at the current room temperature, humidity and barometric pressure to be accurate with this measurement.
And yes, I am aware that if I used wood screws to attach my hardware this is a non-issue, but that is not the point!
Cheers.
Thanks semguigui.
I will search around for some sort of material as you suggested to make a gasket out of.
In case anyone else is reading this thread I have encountered another problem.
-- I am going to apply a grill to the front of the cabinet.
-- The position (in the vertical) of the speaker means that at the apex of the speaker I only have roughly 3/8" (9.52mm) space for the grill frame. I of course will apply a radius cut out to my frame but 3/8" is not very wide and will not be all that strong.
-- I was planning to utilize 'Super Velcro Discs' to attach the which would mean a lot of tugging to get the grill off and I am worried that the 3/8" portion will be pretty week.
I am not all that familiar with Thiele / Small parameters and can find no information pertaining to whether or not the location of the speaker and port are relevant (at least in the vertical plane). If they are not relevant I will move the speaker down and the port a little to the right,
I have asked Dr. Decibel and will post their response when I get it.
Received the F12-X200's today.
There is not a gasket in the box for front mounting the speaker.
It is my understanding that the cabinet should be as air tight as possible (save for the port).
semguigui:
Did you use some sort of gasket material when you built your cabinet?
If so what did you use.
-- I do not want to use the standard Celestion gasket pieces which I believe are pretty much made to apply to the front of the speaker for rear loading. This seems like a less than desirable option as the Celestion gasket material is pretty thick. Or am I wrong?
-- I am thinking of using automotive from-A-gasket.
Thanks for the input semguigui.
Yes the cabinet is pretty heavy for a 1X12.
-- 13 ply 18mm Baltic Birch is a lot heavier than standard plywood.
-- The box is larger than a standard 1x12 due to the fact that it is designed with Thiele / Small parameters (the internal volume is needed).
-- Even if it ends up weighing 40Lbs it is much better than my current Gemini 2 powered cabinet (70Lbs).
//===================================================
Dr. Decibel response (Wadding / batting question).
-- Yes 'wadding' is also referred to as batting.
Batting weight (light, medium, heavy or ultra)
-- The light density is what should be used.
I have received a response from Dr. Decibel!
He / She said:
The wadding isn’t essential, but it fools the speaker into thinking the air volume in the cabinet is greater than
it actually is: it smooths out and extends the low end a bit.
I did not ask the Dr. all of the things I stated in my original post, I simply asked them 'what is the polyester wadding for?'
Perhaps the Dr. has a Kemper account. If so I will direct them to this posting, perhaps they will choose to answer here.
I am going to build a pair of FRFR cabinets and load them with the Celestion F12-X200's.
-- I am going to follow the Celestion Cabinet Design for this.
-- Yes I am aware of the Kemper Kone.
-- Yes I am aware that Zilla Cabs will build me one, but I am a hobbyist wood worker and want to do it myself.
-- I am doing this simply to see how my Profiler will sound in a true FRFR Thiele environment, I.e. removing
all of the speaker and cabinet coloration I can from the equation.
-- I want to see how close it would get to the tone I hear through my audio interface and a pair of 20Hz-20kHz studio monitors.
In the design specification comments with the PDF it says:
'Polyester wadding recommended, affix using staples'.
Being an exacting anal programmer I have a problem with this statement:
-- What is 'polyester wadding'? I am state side and am assuming this is polyester batting as in sold by the yard at fabric stores.
-- If I am correct about this I see that batting comes in different 'weights' (light, mid, heavy and ultra). Would the weight matter?
-- Do a line the entire interior of the cabinet with the batting?
I am pretty sure the 'polyester wadding' is there for sound deadening. I am used to using
Owen Cornings 703 and sometimes Roxul for sound deadening applications.
Since the Celestion design is clearly for a DIY'r (wood glue, screws, table saw, jig saw is really all that is required)
perhaps the suggestion for 'polyester wadding' is their because it is readily available?
On the other hand if I where to utilize Owen Cornings 703 it is denser and thicker (1") and therefore would muck with the
Thiele design of the box (less internal volume).
Crap!
My anal tendencies have me frozen like a deer in the head lights!
I asked this question of Dr. Decibal at Celestion and have received no response.
I suspect they think I am crazy.
Opinions (and I understand that is what they would be) on guidance are most welcome.
Cheers.
Thanks, I was thinking about trying to find a rackmount enclosure to put the amps in, but it would make things easier to just have one power supply. I just wasn't sure if the newer amps were any better, because I can deal with the hassle of having two amps.
Well, if you are a 19" rack guy like me why not just go with a Palmer Macht 402?
Yes, building your own power amp is of course fun and interesting to do.
Yes, having a powered cabinet is also a fun thing to do.
But if you already have a 19" rack and lug it to gigs then I would simply go with the Power Macht 402 (German made, $399.00 state side).
Dual channel 200 Watts per @ 4 Ohm.
Yes it has tone controls, but at zero they are de-activated.
If you are interested, in order to keep this thread clean perhaps one should start a new thread 'Power Macht 402, External Power'.
Or Search for 'external power'. There is another thread here talking about external power amps / sources.
And no, I do not work for Palmer or any retailer that sells them.
Perhaps resale value (to Helix, AXE,ISP, GT-1000,.. users) when you decide that the concept is not for you?
It's a hobby.
Technically a class D power amp consumes no wattage if there is no signal to amplify
The amplification stage is not engaged without something to amplify.
One could add a power switch (which is what I would do).
The reality is you could simply just plug in your power cord.
ICEPower in an enclosed cabinet still has a thermal question.
If you are in your bedroom and would not mind a rack unit look at the Palmer Macht 402. It is around $420.00 U.S.
Yes one could DIY ICEPower modules for at least 1/2 the price.
Some stuff from ICEPower200ASC manuals relating to heat:
Even with the high efficiency of the ICEpower200ASC module, proper thermal design is very important.
When doing the thermal design and tests it is important to note that the amplifiers are to be used for
music signal reproduction. Thorough investigations have shown that the RMS level of any music signal
does not normally exceed 1/8th of the peak value. Consequently, pink noise with an RMS level corresponding
to 1/8th of the rated maximum power should be used as the worst-case signal along with various music signals.
The ICEpower200ASC module has full onboard thermal protection for both the power supply and amplifier section.
This protection circuitry shuts down the module if the temperature reaches critical levels.
Please note that in case of thermal shutdown the module must be reset by disconnecting the mains.
And:
Thermal design is generally a great challenge in power amplifier systems. Linear amplifier designs operating
in class A or AB are normally very inefficient and therefore equipped with extensive heat sinking to keep the
transistor junction temperature low. The ICEpower200ASC is based on highly efficient ICEpower switching technology
providing high overall efficiency characteristics at all levels of operation.
Part of the “component” philosophy of the ASC–series is to provide a self-cooled component thus eliminating the
need for special attention to thermal design.
The ICEpower200ASC module is designed for music reproduction, which means that the output power of the amplifier
will never be continuous. If the average power exceeds 40W @ 4Ω (typical) for a long time at 25°C ambient temperature,
the module will reach its maximum allowable temperature and the temperature protection will be activated. At 50°C ambient
temperature more than 25W @ 4Ω (typical) average power will activate the temperature protection.
//========================================================
25 Celsius = 77 Fahrenheit
50 Celsius = 122 Fahrenheit
//========================================================
I only have a crude understanding of Class D amplification.
Amplification occurs ONLY when their is a signal at the input. Amplification=heat.
Class A the amplification is always occurring whether or not a signal is present.
Class A/B the amplification about half of a class A.
The ICEPower200ASC does not contain a heat sink.
Larger ICEPower amplifiers (500,1000) do contain built in heat sinks and contain plenty of thermal
testing / warnings in their manuals along with suggestions for fans under 'severe' conditions and additional heat sinks.
So, to be honest, I have no idea what any of this means in the real world!
To bad Whippinpost does not have a thermal probe he could insert into his cabinet which would allow
him to produce a log of ambient temperature / time for us!
Also, 200ASC
Earlier on this GIANT thread someone mentioned heat and the 200ASC.
It is my understanding that Seymour Duncan PowerStage utilizes ICEPower.
Note: It has a fan!
Maybe this is due to the small form factor of the SD PowerStage?
ICEPower based power plates (like the miniDSP PWR-ICE250) have a heat sink. Also the miniDP PWR-ICE250 manual states:
'
Ventilation and heat sink
The heat sink is provided to ensure reliable operation of the Amplifier Unit and to protect it from overheating. The heat sink must not be blocked or covered. This product should not be installed unless proper ventilation is provided or manufacturer’s instructions have been adhered to.
'
This would lead me to believe that thermal overload is very possible on a hot stage in a hot club with an ICEPower ASC200 stuffed into such a small un-vented cabinet as the Kemper Kab.
I can only assume that the SD Power Stage probably does not have a heat sink (therefore the fan) and the PWR-ICE250 has a heat sink but requires static ventilation.
Crap!
I am raining on my own parade!
I started reading this thread as I thought I would build my own powered cabinet (Hobbyist wood worker here) for a Kemper Kone as I have an unpowered profiler and am tired of lugging my 70Lb+powered Mission Gemini II around. But thermal dissipation bothers me. If I could find a plate that was punched for a 1/4" jack, IEC320 C14 Rocker Switch / Male power inlet and fan opening I would attempt it, but good luck to me in that endeavor!
If I did find a satisfactory way to mount a fan, I would then need to 'vent' my cabinet in order to produce air flow. If I did that I would have to hear from those who know better than I and would say the cabinet needs to be air tight!
So, $480.00 for a Kemper Kab and $178.00 for a TC BAM 200 is no longer sounding that unreasonable to me.
Opinions are of course invited.
Cheers.
.
Again, excuse my ignorance.
Is tying the shield and ground together actually better / the same as using an unbalanced to balanced converter?
Thanks
To those whom have worked with the 200ASC
The manual says the inputs are balanced.
The Kemper Monitor output is unbalanced (is it not?)
How is this working?
(Excuse my ignorance).
My intention here is to attempt to assists those whom may not be all that computer savvy (meaning do not want to spend the time to learn regular expression syntax).
Being a programmer I was going to write an application to do this.
I found a reference in some other thread here to 'Bulk Rename Utility.exe'.
So:
http://www.bulkrenameutility.co.uk/Download.php
- Download the 'Bulk Rename Utility, version 3.0.0.1 "No-Installer'.
- Open the BRU_NopInstall.zip in Explorer and copy the appropriate (x86 or x64) Bulk Rename Utility.exe
to some other directory where you can run it from.
Copy the .wav files out of one of the Celestion zip files into an empty directory. Do not copy the Celestion.zip
directories (I.e. Shure SM57), but rather copy the individual .wav filed out of the directories. One should have 33 files
for a closed back configuration, and 34 files for an open back configuration.
I am using Celestion_G12M_Greenback_1x12_Open-Back_44-1kHz_200ms.zip as an example.
Create a .txt file.
The format of the file is OriginalFileName|NewFileName
Note: If you cut and paste me example GreenBack1X12Open.txt into something like Notepad.exe
make sure it is in fact ANSI as I do not know if the Bulk Rename Utility.exe will accept Unicode,UTF-8,..
it does accept ANSI:
- File->Save As
- The 'Encoding' at the bottom of the 'Save As' dialog needs to say ANSI. If it does not
then change it to ANSI and save the file.
As an example here is the contents of my GreenBack1X12Open.txt:
G12M Greenbk 112 O Hi-Gn 121+57 Celestion.wav|G12M Gr 1O Hi 121+57.wav
G12M Greenbk 112 O Hi-Gn 421+121 Celestion.wav|G12M Gr 1O Hi 421+121.wav
G12M Greenbk 112 O Hi-Gn 421+57 Celestion.wav|G12M Gr 1O Hi 421+57.wav
G12M Greenbk 112 O Hi-Gn All Celestion.wav|G12M Gr 1O Hi All.wav
G12M Greenbk 112 O Hi-Gn All+Room Mono Celestion.wav|G12M Gr 1O Hi All+Rm Mono.wav
G12M Greenbk 112 O Hi-Gn All+Room Stereo Celestion.wav|G12M Gr 1O Hi All+Rm Stereo.wav
G12M Greenbk 112 O Lo-Gn 121+57 Celestion.wav|G12M Gr 1O Lo 121+57.wav
G12M Greenbk 112 O Lo-Gn 421+121 Celestion.wav|G12M Gr 1O Lo 421+121.wav
G12M Greenbk 112 O Lo-Gn 421+57 Celestion.wav|G12M Gr 1O Lo 421+57.wav
G12M Greenbk 112 O Lo-Gn All Celestion.wav|G12M Gr 1O Lo All.wav
G12M Greenbk 112 O Lo-Gn All+Room Mono Celestion.wav|G12M Gr 1O Lo All+Rm Mono.wav
G12M Greenbk 112 O Lo-Gn All+Room Stereo Celestion.wav|G12M Gr 1O Lo All+Rm Stereo.wav
G12M Greenbk 112 O MD421 Balanced Celestion.wav|G12M Gr 1O MD421 Balanced.wav
G12M Greenbk 112 O MD421 Bright Celestion.wav|G12M Gr 1O MD421 Bright.wav
G12M Greenbk 112 O MD421 Dark Celestion.wav|G12M Gr 1O MD421 Dark.wav
G12M Greenbk 112 O MD421 Dark2 Celestion.wav|G12M Gr 1O MD421 Dark2.wav
G12M Greenbk 112 O MD421 Fat Celestion.wav|G12M Gr 1O MD421 Fat.wav
G12M Greenbk 112 O MD421 Thin Celestion.wav|G12M Gr 1O MD421 Thin.wav
G12M Greenbk 112 O R-121 Balanced Celestion.wav|G12M Gr 1O R-121 Balanced.wav
G12M Greenbk 112 O R-121 Bright Celestion.wav|G12M Gr 1O R-121 Bright.wav
G12M Greenbk 112 O R-121 Dark Celestion.wav|G12M Gr 1O R-121 Dark.wav
G12M Greenbk 112 O R-121 Dark2 Celestion.wav|G12M Gr 1O R-121 Dark2.wav
G12M Greenbk 112 O R-121 Fat Celestion.wav|G12M Gr 1O R-121 Fat.wav
G12M Greenbk 112 O R-121 Thin Celestion.wav|G12M Gr 1O R-121 Thin.wav
G12M Greenbk 112 O SM57 Balanced Celestion.wav|G12M Gr 1O SM57 Balanced.wav
G12M Greenbk 112 O SM57 Bright Celestion.wav|G12M Gr 1O SM57 Bright.wav
G12M Greenbk 112 O SM57 Dark Celestion.wav|G12M Gr 1O SM57 Dark.wav
G12M Greenbk 112 O SM57 Dark2 Celestion.wav|G12M Gr 1O SM57 Dark2.wav
G12M Greenbk 112 O SM57 Fat Celestion.wav|G12M Gr 1O SM57 Fat.wav
G12M Greenbk 112 O SM57 Rear Celestion.wav|G12M Gr 1O SM57 Rear.wav
G12M Greenbk 112 O SM57 Thin Celestion.wav|G12M Gr 1O SM57 Thin.wav
G12M Greenbk 112 O TLM 107 Room Stereo Celestion.wav|G12M Gr 1O TLM107 Rm Stereo.wav
G12M Greenbk 112 O TLM 107 RoomL Celestion.wav|G12M Gr 1O TLM107 RmL.wav
G12M Greenbk 112 O TLM 107 RoomR Celestion.wav|G12M Gr 1O TLM107 RmR.wav
Double click on 'Bulk Rename Utility.exe' to start it.
1. Select the 'folder' where you un-ziped the IR's to (From the 'This PC' tree control)
2. Actions->Select All
3. Note the Name and New Name are identical.
4. Actions->Import Rename Pairs. Navigate to and select your .txt file (GreenBack1X12Open.txt)
5. Note the Name and New Name for the files noted in the text file are now different.
6. Click on the 'Rename' button (lower left corner).
Done.
Do yourself a favor:
- Zip up all of the newly named IR's into another zip file for back up purposes. That
way you will never need to do this again.
Different Celestion IR .zips.
Example: Celestion_G12M_Greenback_2x12_Closed-Back_44-1kHz_200ms.zip
- Save your GreenBack1X12Open.txt to another file name ('Save As', Mine is GreenBack2X12Closed.txt)
- I am assuming you are using Notepad.exe
- Edit->Replace:
-- Find what: 112
-- Replace with: 212
-- Click on 'Replace all.
- The'O' in 1O below is an O (for open) not a zero.
- Edit->Replace:
-- Find what: 1O
-- Replace with: 2C
-- Click on 'Replace all.
- We now want to replace the [Space]O[Space] in the original file names with [Space]C[Space].
The [Space] I am talking about is the actual space bar. So [Space]O[Space} is hit the space bar,
hit the O, hit the space bar.
- Edit->Replace:
-- Find what: [Space]O[Space]
-- Replace with: [Space]C[Space]
-- Click on 'Replace all.
- Closed back IR's do not have a rear SM57, so delete the line
'G12M Greenbk 212 C SM57 Rear Celestion.wav|G12M Gr 2C SM57 Rear.wav'
- Save the file.
Repeat the process 'Double click on 'Bulk Rename Utility.exe' to start it.' above but this
time use the GreenBack2X12Closed.txt for the Rename Pairs file.
Once I had created my original file (GreenBack1X12Open.txt) I renamed the contents of the entire Greenback
collection (1x12 Closed, 1X12 Open, 2x12 Closed, 2X12 Open and 4x12 Closed) in less than 15 minutes.
Good luck.
