Amp sounds better at 45 degree angle ...

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Hi , I built this amp a few months ago and it sounds great accept it sounds best when I stand at a 45 degree angle to the speaker , the closer I move to directly in front of the speaker the more tinny and brittle it sounds , it doesn"t sound bad but just not as good as at 45 degrees .....

So the first question I guess is why ?? (some sort of phaze thing ?? )

Second question is how can I get the sound directly in front of the speaker to sound like it does at a 45 degree angle ??

Thanx

PS: The amp has a solidstate overdrive stage then into two 12ax7 stages (one 12ax7 tube) , then into some analogue speaker simulators , then into 4 12ax7 stages (two 12ax7 tubes) then into a tone stack , then through the effects loop into a BBE sonic maximizer , then into a 15 band EQ and then into a DBX compressor and then into a LM3886 power amp into a 12 inch Celestian 50w speaker ......
 
PS: The amp has a solidstate overdrive stage then into two 12ax7 stages (one 12ax7 tube) , then into some analogue speaker simulators , then into 4 12ax7 stages (two 12ax7 tubes) then into a tone stack , then through the effects loop into a BBE sonic maximizer , then into a 15 band EQ and then into a DBX compressor and then into a LM3886 power amp into a 12 inch Celestian 50w speaker ......

Be glad that it puts out a signal :eek:
But more seriously, I think it has more to do with the loudspeakers, especially when it is a multi-way; these can have phase issues which depend on listening distance and angle.
 
...the closer I move to directly in front of the speaker the more tinny and brittle it sounds , it doesn"t sound bad but just not as good as at 45 degrees ...
I guess most if the treble is being thrown forward. If you equalize it to sound good on axis, then it'll probably sound dull at 45 degrees. Maybe you could mount something directly in front of the cone to soak up some treble or scatter it around?
 

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It is normal that a driver that large beams.
If you search around you will find a whole bunch of info about miking of guitar amps for PA or recording where they discuss about the best spot in front of a speaker to place a microphone. And guess what ? There is no such best place because it is a matter of taste.
There was once an article in JAES where thy made masurements with different mic angles and placements in front of a guitar amp and they show remarkable differences in frequency response.

In other words: What you encounter is perfectly normal.

There are different ways to cope with it however:

Listen to it off axis only - this is what needs the least effort. When you practice with a band your mates will most probably hear the off-axis sound only and you will probably be glad to stand on-axis now and then where it has the necessary bite to cut through the rest.

The "anti beaming thingie" can be tried out with other things first to see whether you like it.

And last but not least you could try to correct the frequency response a little within the amp.

You would have to try ount decide what works for you and what you like most.

Regards

Charles
 
Well I used a round piece of memory foam about 4 in across and mounted it on the grill in front of the center of the speaker and it helped quite a bit , It made the sweet spot larger but I still could not be directly in front of it without being blasted with trebble ..... I"ll try a bigger piece next ......

Thanx guys .....
 
Putting something in front of the speaker is not such a good idea, firstly because it will lead to a lot of hard to predict interference problems. This translates into a ragged frequency response. Secondly, in effect you create a ring radiator, which has twice the directivity of a pistonic radiator. Hence, it is bound to exacerbate the beaming problem, rather than ameliorating it.

Therefore, the best solution would be to cross-over and use a smaller transducer for the high end, or a transducer with controlled directivity. Try a cheap horn crossed over at 1500-2000 Hz and your problem will be solved.

vac
 
You're talking about ragged frequency response, from a 12" guitar speaker.

I doubt that the speaker would end up a perfect ring radiator, but I suspect the outcome to be preferable to a laser beam of deafening treble, with everyone off-axis struggling to hear the guitar cut through.

Chris
 
You're talking about ragged frequency response, from a 12" guitar speaker.

:rofl:

Kind of a given, isn't it?


Truth is, many players like the sound of "beam blockers". They also like speakers mounted on the back of the baffle, and they miss the deep frame around the edge of the cabinet if you take it off. They like thick grille cloth and ports that leak midrange. They prefer 4x12s and 4x10s rather than a point source because of the interference patterns.

Technically, the problem with trying to fix the beam is you'll also mess up the off-axis response, and that's what most people in the room are listening to.

Remember, guitar speakers are not mic'd on axis. Unlike hifi speakers, if you sit on axis with a guitar speaker, you're not hearing the speaker at its best. I'm not sure I buy into the idea that since the on-axis beam of a guitar speaker sounds harsh and piercing, the secret to good tone is to spread that sound around the room. ;)
 
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