Shakers - Simple/Cheap Hookup - Visual Guide - Page 97 - AVS Forum | Home Theater Discussions And Reviews
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post #2881 of 2897 Old 06-25-2019, 07:30 AM
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Originally Posted by pjp View Post
I think that model allows you to assign the unused channel amps to zone 2, which means you can feed LFE into zone 2 to drive shakers directly with that unused internal amp.

Dang, I am not seeing a way that I can find, but I asked on the owners thread for the amp too.
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post #2882 of 2897 Old 06-25-2019, 10:59 PM
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Originally Posted by pjp View Post
I think that model allows you to assign the unused channel amps to zone 2, which means you can feed LFE into zone 2 to drive shakers directly with that unused internal amp.

Dang, I am not seeing a way that I can find, but I asked on the owners thread for the amp too.
Post #2860 in this thread explains how to do it.
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post #2883 of 2897 Old 08-16-2019, 11:31 AM
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Hello! I need some help figuring out how to power two Reckhorn BS-200i's. I'd rather not buy a plate amp because 1. I'm too lazy to put together a DIY case for it and 2. They're massive. However I have found a "Nobsound G2 PRO 300W" amp on amazon.co.uk (please look it up if you can, I can't post links with < 5 posts...) Would the low pass frequency filter on that thing work if I split the SUB out on it and wired up the shakers serially to that? If so, am I good to go in using it for this purpose?

Attaching the product image of the amp.

Thanks!
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post #2884 of 2897 Old 08-16-2019, 12:10 PM
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Hello! I need some help figuring out how to power two Reckhorn BS-200i's. I'd rather not buy a plate amp because 1. I'm too lazy to put together a DIY case for it and 2. They're massive. However I have found a "Nobsound G2 PRO 300W" amp on amazon.co.uk (please look it up if you can, I can't post links with < 5 posts...) Would the low pass frequency filter on that thing work if I split the SUB out on it and wired up the shakers serially to that? If so, am I good to go in using it for this purpose?

Attaching the product image of the amp.

Thanks!
It will probably work. It would be good to find out what the lowest setting is on the crossover because the shakers need to be cut-off lower than subs. There's a very good chance it will be fine, but wouldn't hurt to check in advance.

I think the theoretical max you can get with a 32v/5a power supply is 160 watts. According to the Amazon US listing the seller says 300W @2Ω ; 170W @4Ω ; 80W @8Ω -- I don't think this is accurate, but it suggests you would get the most power by wiring your 4ohm shakers in parallel to to create a 2 ohm load. Normally 2 ohms strains amps, but apparently this amp is fine with it if the listing is to be believed. I'd put an ohmmeter on the shakers when you have them in parallel just to make sure they are around 2ish ohms (above is fine, significantly below 2 may not be). Even if the amp doesn't produce the power it claims, I suspect it will be more than enough for two shakers, though I haven't tried those particular shakers. I'm driving 4 Aura Pro's with a 100 watt and it is more than enough.
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post #2885 of 2897 Old 08-16-2019, 12:19 PM
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It will probably work. It would be good to find out what the lowest setting is on the crossover because the shakers need to be cut-off lower than subs. There's a very good chance it will be fine, but wouldn't hurt to check in advance.

I think the theoretical max you can get with a 32v/5a power supply is 160 watts. According to the Amazon US listing the seller says 300W @2Ω ; 170W @4Ω ; 80W @8Ω -- I don't think this is accurate, but it suggests you would get the most power by wiring your 4ohm shakers in parallel to to create a 2 ohm load. Normally 2 ohms strains amps, but apparently this amp is fine with it if the listing is to be believed. I'd put an ohmmeter on the shakers when you have them in parallel just to make sure they are around 2ish ohms (above is fine, significantly below 2 may not be). Even if the amp doesn't produce the power it claims, I suspect it will be more than enough for two shakers, though I haven't tried those particular shakers. I'm driving 4 Aura Pro's with a 100 watt and it is more than enough.
Thank you! According to the listing it should go down to 40 Hz, so that should be fine. I'm no electrician so bear with me here but is the SUB OUT "powered"? In the listing it shows connecting an actively powered sub to the SUB OUT and not passive as the shakers are. Or is it only the R/L outs that are "powered" (but might not adhere to the sub frequency filter?) Trying to wrap my head around this.
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post #2886 of 2897 Old 08-16-2019, 12:41 PM
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Thank you! According to the listing it should go down to 40 Hz, so that should be fine. I'm no electrician so bear with me here but is the SUB OUT "powered"? In the listing it shows connecting an actively powered sub to the SUB OUT and not passive as the shakers are. Or is it only the R/L outs that are "powered" (but might not adhere to the sub frequency filter?) Trying to wrap my head around this.


The "sub out" single RCA jack on the back of the amp is a line-level output to feed an active sub or another shaker amp if you wanted to add one later. The "speaker out" positive and negative output are for driving the shakers (or passive subs). I would guess that the line-level sub out signal is the low-pass signal from the crossover, but you shouldn't need to use that output anyway.

40hz cuttoff should be just low enough. If you set it too high, you will get bleed-through of sounds that should create shaking, normally 40hz would be low enough if it's accurate.
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post #2887 of 2897 Old 08-16-2019, 12:54 PM
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The "sub out" single RCA jack on the back of the amp is a line-level output to feed an active sub or another shaker amp if you wanted to add one later. The "speaker out" positive and negative output are for driving the shakers (or passive subs). I would guess that the line-level sub out signal is the low-pass signal from the crossover, but you shouldn't need to use that output anyway.

40hz cuttoff should be just low enough. If you set it too high, you will get bleed-through of sounds that should create shaking, normally 40hz would be low enough if it's accurate.
Great, thank you. So you think the frequency filter also applies to the speaker outs then? (Reason I'm unsure is because someone said the filter would only apply to the sub out, this was regarding a different amp though (the "Nobsound Mini 2.1 Channel" on ebay)).
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post #2888 of 2897 Old 08-16-2019, 01:08 PM
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Great, thank you. So you think the frequency filter also applies to the speaker outs then? (Reason I'm unsure is because someone said the filter would only apply to the sub out, this was regarding a different amp though (the "Nobsound Mini 2.1 Channel" on ebay)).
It's sounds like it's a dual mode amp -- when the switch is in PBTL position, it bypasses the sub crossover (to be used as one mono full-range amp) and when the switch is in SUB position, the crossover is in effect for the speaker outputs. You would have it switched to SUB. I haven't tried this amp personally, but this is what I infer from the description.

The fact that it has gain switches to bump up the line level input is a very nice feature for use with shakers. This seems like a really good choice for a shaker amp.

Last edited by pjp; 08-16-2019 at 01:14 PM.
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post #2889 of 2897 Old 08-16-2019, 01:14 PM
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It's sounds like it's a dual mode amp -- when the switch is in PBTL position, it bypasses the sub crossover (to be used as one mono full-range amp) and when the switch is in SUB position, the crossover is in effect for the speaker outputs. You would have it switched to SUB. I haven't tried this amp personally, but this is what I infer from the description.
Sounds good! Thanks a lot for the help.
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post #2890 of 2897 Old 08-30-2019, 02:51 AM
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So all my bass shaker gear has arrived and been installed. First impression is... alright? Not quite what I was expecting but still a pleasant addition. But I am wondering if I can still improve the experience.



One thing I have noticed is that the shakes are delayed just enough to be annoying, making them feel a bit random rather than tied directly to what is happening on screen (estimating a couple hundred milliseconds delay). What is the most likely culprit for these delays, the amp, shakers or my receiver (Sony STR-DN1080)? Is there something that can be done about it?


Another thing is that the shakers are rated at 100W RMS and 200W impulse power over 2 seconds (that's what the box says anyway). I have two of them wired serially to the amp, which means they are running at 8 Ohm and thus get half the power. 300W amp -> 2 shakers @ 8 Ohm = 300 / 2 / 2 = 75W each? (Please correct my math if it is wrong, I don't really understand electricity). Would the shakers be power starved in this configuration, and if so how do I wire two shakers in parallel to an amp with one set of outputs?



And the last thing is that the shakes seem to be falling off heavily going from 40 Hz down to 30 Hz and lower, shouldn't it get deeper and more rumblier instead of quieting down?


Lots of questions I know but I would very much appreciate some help with my setup.
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post #2891 of 2897 Old 08-30-2019, 07:50 AM
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So all my bass shaker gear has arrived and been installed. First impression is... alright? Not quite what I was expecting but still a pleasant addition. But I am wondering if I can still improve the experience.



One thing I have noticed is that the shakes are delayed just enough to be annoying, making them feel a bit random rather than tied directly to what is happening on screen (estimating a couple hundred milliseconds delay). What is the most likely culprit for these delays, the amp, shakers or my receiver (Sony STR-DN1080)? Is there something that can be done about it?


Another thing is that the shakers are rated at 100W RMS and 200W impulse power over 2 seconds (that's what the box says anyway). I have two of them wired serially to the amp, which means they are running at 8 Ohm and thus get half the power. 300W amp -> 2 shakers @ 8 Ohm = 300 / 2 / 2 = 75W each? (Please correct my math if it is wrong, I don't really understand electricity). Would the shakers be power starved in this configuration, and if so how do I wire two shakers in parallel to an amp with one set of outputs?



And the last thing is that the shakes seem to be falling off heavily going from 40 Hz down to 30 Hz and lower, shouldn't it get deeper and more rumblier instead of quieting down?


Lots of questions I know but I would very much appreciate some help with my setup.
The shakers will be awesome. It's inescapable. Just need to get them tuned right. What do you have the PBTL switch set to and what crossover frequency are you using on the Nobsound amp? Also, what output on the Sony are you using to drive the Nobsound amp?
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post #2892 of 2897 Old 08-30-2019, 08:55 AM
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The shakers will be awesome. It's inescapable. Just need to get them tuned right. What do you have the PBTL switch set to and what crossover frequency are you using on the Nobsound amp? Also, what output on the Sony are you using to drive the Nobsound amp?
Hello again! The PBTL switch is set to SUB and the crossover is at its lowest (which should be 40Hz?). I've also enabled the small gain switches on the bottom of the amp. The amp is connected via a 1x to 2x RCA splitter going out from one of the SUBWOOFER OUTputs shown bottom middle-left on this picture.

Last edited by Dockson; 08-30-2019 at 10:24 AM.
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post #2893 of 2897 Old 08-30-2019, 10:53 AM
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Hello again! The PBTL switch is set to SUB and the crossover is at its lowest (which should be 40Hz?). I've also enabled the small gain switches on the bottom of the amp. The amp is connected via a 1x to 2x RCA splitter going out from one of the SUBWOOFER OUT inputs shown bottom middle-left on this picture.
Those connections and settings are correct, which is very weird because it seems like the low-pass crossover isn't working at all based upon your symptoms. I would first try moving the Nobsound crossover over the full range just make sure it's working (shaking should get more intense and inappropriate as you raise it). If that crossover isn't working, then maybe try switching to PBTL just for kicks to see if the crossover is in the circuit then.

For the delay you are experiencing, nothing in the shakers or amp can add any delay -- the shaker/amp is exactly like a powered subwoofer or even a powered speaker (if you put a full-range signal through, you will hear music coming out of the shakers). If there is an actual delay, it would have to be in the Sony because it is the only device capable of adding a delay, but it seems unlikely unless your sub is also out of sync (or all of the audio is out of sync). Are you also running a sub and is it out of sync? Is the overall audio out of sync?

As far as power, typically shakers don't require that much power to do their thing, but I have no experience with your shakers. I think I remember reading that that amp can handle 2 ohm, so if your shakers are 4 ohm, you could wire them in parallel to make them a 2 ohm load and get more power out of the amp. The 8 ohm load is much friendlier to the amp, so I would leave it as is unless (once everything is tuned correctly) you find the amp can't provide enough shaking power. I like to limit power to shakers to only the amount needed -- if you have too much power, unpredictable spikes in movie content can damage the shakers or maybe even the furniture (depending on what it's bolted to), so having just enough power is better than too much in my opinion.

As far as not feeling the lowest frequencies -- I feel like all of this (and maybe the perceived delay) is due to the shaker crossover somehow being too high. I'm not sure how that's possible, but that seems like the most likely situation. If the shaker crossover is too high, you will get a lot more shaking at upper frequencies (that should not generate shaking at all) and the lower actual shake content will be barely present. Once you can crank down the shaker crossover, you will be able turn up the gain to feel the lowest shake frequencies in balance with everything else. The other thing to look at is the subwoofer setting in the Sony to make sure it doesn't have some kind of subsonic filter on to filter out the lowest frequencies (which would make sense to protect smaller subs, but not for shakers).
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post #2894 of 2897 Old 08-30-2019, 11:25 AM
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Those connections and settings are correct, which is very weird because it seems like the low-pass crossover isn't working at all based upon your symptoms. I would first try moving the Nobsound crossover over the full range just make sure it's working (shaking should get more intense and inappropriate as you raise it). If that crossover isn't working, then maybe try switching to PBTL just for kicks to see if the crossover is in the circuit then.

For the delay you are experiencing, nothing in the shakers or amp can add any delay -- the shaker/amp is exactly like a powered subwoofer or even a powered speaker (if you put a full-range signal through, you will hear music coming out of the shakers). If there is an actual delay, it would have to be in the Sony because it is the only device capable of adding a delay, but it seems unlikely unless your sub is also out of sync (or all of the audio is out of sync). Are you also running a sub and is it out of sync? Is the overall audio out of sync?

As far as power, typically shakers don't require that much power to do their thing, but I have no experience with your shakers. I think I remember reading that that amp can handle 2 ohm, so if your shakers are 4 ohm, you could wire them in parallel to make them a 2 ohm load and get more power out of the amp. The 8 ohm load is much friendlier to the amp, so I would leave it as is unless (once everything is tuned correctly) you find the amp can't provide enough shaking power. I like to limit power to shakers to only the amount needed -- if you have too much power, unpredictable spikes in movie content can damage the shakers or maybe even the furniture (depending on what it's bolted to), so having just enough power is better than too much in my opinion.

As far as not feeling the lowest frequencies -- I feel like all of this (and maybe the perceived delay) is due to the shaker crossover somehow being too high. I'm not sure how that's possible, but that seems like the most likely situation. If the shaker crossover is too high, you will get a lot more shaking at upper frequencies (that should not generate shaking at all) and the lower actual shake content will be barely present. Once you can crank down the shaker crossover, you will be able turn up the gain to feel the lowest shake frequencies in balance with everything else. The other thing to look at is the subwoofer setting in the Sony to make sure it doesn't have some kind of subsonic filter on to filter out the lowest frequencies (which would make sense to protect smaller subs, but not for shakers).
Thank you for the extensive reply. The frequency knob at least changes how the shakers respond but most of my problems do indeed seem to be related to the frequency response of the shakers being out of whack. I tried watching
and rating the shakiness out of 5 for the different frequencies and got this:


1-5Hz 0/5

10Hz 0.5/5

20Hz 2/5
25Hz 1.5/5
30Hz 1/5
35Hz 1.5/5
40Hz 2/5
45Hz 3.5/5
50Hz 4.5/5
55Hz 3.5/5
60Hz 2/5
65Hz 1.5/5
70Hz 1/5


So it peaks at 50Hz and doesn't do much at all between 1-40 Hz. I checked my receiver settings and couldn't find anything related to filtering low frequencies, just a high frequency filter which I turned off anyway. The out of sync issue I'm having might just be that I'm missing all of the low frequencies and just hearing the high ones.
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post #2895 of 2897 Old 08-30-2019, 11:53 AM
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Thank you for the extensive reply. The frequency knob at least changes how the shakers respond but most of my problems do indeed seem to be related to the frequency response of the shakers being out of whack. I tried watching this video and rating the shakiness out of 5 for the different frequencies and got this:


1-5Hz 0/5

10Hz 0.5/5

20Hz 2/5
25Hz 1.5/5
30Hz 1/5
35Hz 1.5/5
40Hz 2/5
45Hz 3.5/5
50Hz 4.5/5
55Hz 3.5/5
60Hz 2/5
65Hz 1.5/5
70Hz 1/5


So it peaks at 50Hz and doesn't do much at all between 1-40 Hz. I checked my receiver settings and couldn't find anything related to filtering low frequencies, just a high frequency filter which I turned off anyway.
Maybe you can repeat the test with your subwoofer by driving the sub with the Nobsound "sub out" RCA instead of the Sony Sub out. This should give you some insight into how the Nobsound crossover works (or doesn't work) taking the shaker out of the equation. The crossovers in those small amps don't tend to be very sophisticated. If the crossover in the amp isn't very good, you can still use the amp by adding an external FMOD RCA insert or an external crossover (then set the amp to PBTL and Sub and figure out which works better in combination with the external crossover).

I'm using this stupid this stupid thing with the shakers in my son's driving rig (https://www.ebay.com/itm/Car-Home-Am...72.m2749.l2649) -- it works with crossover at the lowest level for iRacing -- not sure if it would work for home theater. Many people in this thread have had success using 50hz FMOD, some double them up in series (since they often come in pairs) to get a sharper cutoff slope if I remember correctly.

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I'm having might just be that I'm missing all of the low frequencies and just hearing the high ones.
This is my guess as well.
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post #2896 of 2897 Old 08-30-2019, 12:34 PM
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Maybe you can repeat the test with your subwoofer by driving the sub with the Nobsound "sub out" RCA instead of the Sony Sub out. This should give you some insight into how the Nobsound crossover works (or doesn't work) taking the shaker out of the equation. The crossovers in those small amps don't tend to be very sophisticated. If the crossover in the amp isn't very good, you can still use the amp by adding an external FMOD RCA insert or an external crossover (then set the amp to PBTL and Sub and figure out which works better in combination with the external crossover).

I'm using this stupid this stupid thing with the shakers in my son's driving rig (https://www.ebay.com/itm/Car-Home-Am...72.m2749.l2649) -- it works with crossover at the lowest level for iRacing -- not sure if it would work for home theater. Many people in this thread have had success using 50hz FMOD, some double them up in series (since they often come in pairs) to get a sharper cutoff slope if I remember correctly.



This is my guess as well.
Actually I have no subwoofer at the moment as I live in an apartment building. I've decided to go for this bundle now that I've seen that parts-express actually ships worldwide, so I can try out Dayton Audio gear without having to resort to these unknown brands. With the new amp and shakers I can figure out which of my current hardware is the culprit and return it. I have a feeling it's the amp...
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post #2897 of 2897 Old 09-03-2019, 06:03 AM
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Actually I have no subwoofer at the moment as I live in an apartment building. I've decided to go for this bundle now that I've seen that parts-express actually ships worldwide, so I can try out Dayton Audio gear without having to resort to these unknown brands. With the new amp and shakers I can figure out which of my current hardware is the culprit and return it. I have a feeling it's the amp...
You should be able to get the existing equipment to work pretty easily. The shakers you originally bought have good reviews, so it's very likely just the crossover. Given you have no subwoofer, you should be able to tune the shakers using only the crossover in the Sony AVR. The only reason you typically need a separate shaker crossover is because shakers need to cut off at a lower point than the subs, but you don't have that concern. Try moving the Sony AVR LFE/Sub crossover down to around 40hz and switch your Nobsound to PBTL (it can operate in full range mode because the AVR will cutting out all of the non-shake frequencies). Then use the AVR sub volume level and Nobsound amp volume to balance out the shaking intensity.
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