Studio Reference Monitors

Mark Austin · January 3rd, 2003, 09:06 AM

<<<-- Something else I saw while surfing the 'net was to watch for the crossover specification, specifically for those in the 1.5kHz to 2.0kHz range because of dialogue. What's this mean? -->>>

The reason this becomes critical is that the bulk of the frequencies in the human voice falls in the range between 300Hz to 3Khz. A crossover in the 1.5Khz to 2Khz range falls squarely in the middle of the most sensitive area of our voice (and hearing). Unless it's a very good crossover it will cause problems.

Most passive crossovers use heavy filtering to achieve the nessasary crossover frequency. For example; if you are crossing over at say 1.5k then the filter for the low frequency driver attenuates all frequencies above 1.5k at 12 to 18 db per octave. likewise the high frequency driver filter is going to attenuate all frequencies below 1.5k at 12 to 18 db per octave. The problem is that at exactly 1.5k there will either be a slight rise or fall because the filters cannot cut the bands off at exactly 1.5k either accenting or attenuating the most critical frequency in the vocal range.

The best soultion is to look at systems that crossover at lower frequencies, the 120Hz to 800Hz range, they will still exibit exactly the same problems but since it's not in the most critical range it won't be nearly as noticible.

As a last note, the human voice, although relatively limited in range is the single most critical thing we as people hear, it details emotion, fear, love etc. That's one reason it's so hard to synthisize and so important to reproduce correctly, especially in ENG & filmmaking.

Mark

Mark Austin · January 3rd, 2003, 09:25 AM

<<<-- Originally posted by Mark Austin : When looking at frequency response don't forget the most important factor the +/- db rating; for example a speaker that can go from 20hz to 22khz +/- 6db is not going to be as good as a speaker that goes from 40hz to 20khz +/- 2db by a factor of 40!! Because a 1 db increase or decrease in sound is a factor of 10x more!!! -->>> I

Just to clarify something; +/- 6db is a 12db range and +/- 2db is a 4db range, so my factor of 40x is incorrect. A factor of 5x is more accurate. Keeping in mind that to go 1db more in volume (twice as loud) requres ten times the amplifier power to reproduce, to go from a ~4db range to a ~12db range is ~8db. 8db x 10(x power required)= you get the picture....

This also applies in the crossover question above; if you only have a +1db rise at the crossover point that's twice as loud as it should be.

Mark
(~ = nominal)

Christopher Go · January 6th, 2003, 08:34 AM

Once again, thanks for the thorough explanations Mark. It's not one hundred percent clear to me yet but I do have a better idea what these specifications mean now, probably the best descriptions I've seen on any forum I've visited.

Finally found someplace that sells high end video and audio gear, going to take the suggestions in this thread and hear for myself which speakers to get. Like many other essentials in this field, I'll probably have to go over my budget.

Mark Austin · January 6th, 2003, 08:47 AM

Like most things in life you get what you pay for. There are some exceptions of course.

There is this weird thing in A/V that I have noticed; once you get a product at a certain level, a camera for example, to get one that is 10 to 20% better you have to spend 100% more?

Good luck on your quest, if you have a good magazine shop nearby look for a copy of Mix magazine, Pro Audio Review, or EQ, they are great resources for in-depth reviews of whats on the pro audio (not audiofile) market these days.
Mark

Christopher Go · January 6th, 2003, 09:02 AM

That was going to be another one of my questions but I'm glad you mentioned some references for reputable reviews.

That extra performance does cost lots more - the price difference is apparent in computing too, like the jump from 2.8GHz (~$400) to the 3.0GHz Pentium 4 (~$700).

Jeff Donald · January 6th, 2003, 09:12 AM

Mark,

I just read over this thread and have a question. You state a 1 db change is double the volume. I thought it was a 3db change to double the volume. I'm doing this from memory (20+ years since college) so I'm probably off here. Can you verify?

Jeff

Mark Austin · January 6th, 2003, 09:37 AM

You know you are probably right, I was just pulling the 1db from memory which at this point seems to have failed me....

I just cracked open my dusty copy of The Recording Studio Handbook, John M. Woram; 1982 to be sure, and you are in fact correct.

To paraphrase Mr. Woram; the addition of two sources of equal volume ( 60db + 60db) will result in a percieved two fold volume increase but is actually only measured to be about 3db louder.

Thanks for catching that, I didn't mean to mislead folks. My point is that the difference between 4db & 12db is still pretty substantial.

Mark

(In Texas everything is louder...)

Steve Leone · January 8th, 2003, 02:43 PM

I am using a pair of KRK's...I think they are V6 or something like that....unpowered..they are small, punchy, clean and accurate.....you need a power amp with them . They ran about $300 for the pair, got them at Guitar Center, which is a cool place for buying proaudio gear. Got my mixer there as well.

Christopher Go · January 8th, 2003, 09:17 PM

One of the vendor links provided above was www.americanmusical.com for American Musical Supply. Anyone ever purchase one of their 'Non-factory sealed' merchandise before?

Mark Austin · January 9th, 2003, 06:52 AM

I think is the mail order wing of Guitar Center, if so I'd have no problem using them, great company.
Mark

Rick Foxx · January 9th, 2003, 10:11 AM

<<<-- Originally posted by Mark Austin : I think is the mail order wing of Guitar Center, if so I'd have no problem using them, great company.
Mark -->>>

Actually, Musician's Friend is the Guitar Center mail order front. AMS is (for the moment) independent. I did purchase a non-factory sealed keyboard from AMS a few years ago. It still had the full warranty, and I never had a problem with it.

MIDIMan

Christopher Go · January 20th, 2003, 11:17 PM

I think I've decided on a pair of active Tannoy Reveals. I see they're recommended here and elsewhere. Funny how in the end budgets are always doubled. Want to thank everyone for their help and input, and of course more opinions are always welcome.

January 3rd, 2003, 09:06 AM	#16
Mark Austin Regular Crew Join Date: Nov 2002 Location: Houston, Texas Posts: 188	Crossover frq. <<<-- Something else I saw while surfing the 'net was to watch for the crossover specification, specifically for those in the 1.5kHz to 2.0kHz range because of dialogue. What's this mean? -->>> The reason this becomes critical is that the bulk of the frequencies in the human voice falls in the range between 300Hz to 3Khz. A crossover in the 1.5Khz to 2Khz range falls squarely in the middle of the most sensitive area of our voice (and hearing). Unless it's a very good crossover it will cause problems. Most passive crossovers use heavy filtering to achieve the nessasary crossover frequency. For example; if you are crossing over at say 1.5k then the filter for the low frequency driver attenuates all frequencies above 1.5k at 12 to 18 db per octave. likewise the high frequency driver filter is going to attenuate all frequencies below 1.5k at 12 to 18 db per octave. The problem is that at exactly 1.5k there will either be a slight rise or fall because the filters cannot cut the bands off at exactly 1.5k either accenting or attenuating the most critical frequency in the vocal range. The best soultion is to look at systems that crossover at lower frequencies, the 120Hz to 800Hz range, they will still exibit exactly the same problems but since it's not in the most critical range it won't be nearly as noticible. As a last note, the human voice, although relatively limited in range is the single most critical thing we as people hear, it details emotion, fear, love etc. That's one reason it's so hard to synthisize and so important to reproduce correctly, especially in ENG & filmmaking. Mark __________________ I'm humbled by the greatness that surrounds me.

January 3rd, 2003, 09:25 AM	#17
Mark Austin Regular Crew Join Date: Nov 2002 Location: Houston, Texas Posts: 188	the +/- db rating <<<-- Originally posted by Mark Austin : When looking at frequency response don't forget the most important factor the +/- db rating; for example a speaker that can go from 20hz to 22khz +/- 6db is not going to be as good as a speaker that goes from 40hz to 20khz +/- 2db by a factor of 40!! Because a 1 db increase or decrease in sound is a factor of 10x more!!! -->>> I Just to clarify something; +/- 6db is a 12db range and +/- 2db is a 4db range, so my factor of 40x is incorrect. A factor of 5x is more accurate. Keeping in mind that to go 1db more in volume (twice as loud) requres ten times the amplifier power to reproduce, to go from a ~4db range to a ~12db range is ~8db. 8db x 10(x power required)= you get the picture.... This also applies in the crossover question above; if you only have a +1db rise at the crossover point that's twice as loud as it should be. Mark (~ = nominal) __________________ I'm humbled by the greatness that surrounds me.

January 6th, 2003, 08:47 AM	#19
Mark Austin Regular Crew Join Date: Nov 2002 Location: Houston, Texas Posts: 188	Going over budget Like most things in life you get what you pay for. There are some exceptions of course. There is this weird thing in A/V that I have noticed; once you get a product at a certain level, a camera for example, to get one that is 10 to 20% better you have to spend 100% more? Good luck on your quest, if you have a good magazine shop nearby look for a copy of Mix magazine, Pro Audio Review, or EQ, they are great resources for in-depth reviews of whats on the pro audio (not audiofile) market these days. Mark __________________ I'm humbled by the greatness that surrounds me.

January 6th, 2003, 09:37 AM	#22
Mark Austin Regular Crew Join Date: Nov 2002 Location: Houston, Texas Posts: 188	I stand corrected! You know you are probably right, I was just pulling the 1db from memory which at this point seems to have failed me.... I just cracked open my dusty copy of The Recording Studio Handbook, John M. Woram; 1982 to be sure, and you are in fact correct. To paraphrase Mr. Woram; the addition of two sources of equal volume ( 60db + 60db) will result in a percieved two fold volume increase but is actually only measured to be about 3db louder. Thanks for catching that, I didn't mean to mislead folks. My point is that the difference between 4db & 12db is still pretty substantial. Mark (In Texas everything is louder...) __________________ I'm humbled by the greatness that surrounds me.

January 8th, 2003, 02:43 PM	#23
Steve Leone Regular Crew Join Date: Jan 2003 Location: Boston, MA Posts: 116	Audio Monitors I am using a pair of KRK's...I think they are V6 or something like that....unpowered..they are small, punchy, clean and accurate.....you need a power amp with them . They ran about $300 for the pair, got them at Guitar Center, which is a cool place for buying proaudio gear. Got my mixer there as well. __________________ Omens carry only as much weight as we choose to assign them.

January 6th, 2003, 08:34 AM	#18
Christopher Go Major Player Join Date: Nov 2002 Location: Honolulu, HI Posts: 429	Once again, thanks for the thorough explanations Mark. It's not one hundred percent clear to me yet but I do have a better idea what these specifications mean now, probably the best descriptions I've seen on any forum I've visited. Finally found someplace that sells high end video and audio gear, going to take the suggestions in this thread and hear for myself which speakers to get. Like many other essentials in this field, I'll probably have to go over my budget.

January 6th, 2003, 09:02 AM	#20
Christopher Go Major Player Join Date: Nov 2002 Location: Honolulu, HI Posts: 429	That was going to be another one of my questions but I'm glad you mentioned some references for reputable reviews. That extra performance does cost lots more - the price difference is apparent in computing too, like the jump from 2.8GHz (~$400) to the 3.0GHz Pentium 4 (~$700).

January 6th, 2003, 09:12 AM	#21
Jeff Donald Warden Join Date: Mar 2002 Location: Clearwater, FL Posts: 8,287	Mark, I just read over this thread and have a question. You state a 1 db change is double the volume. I thought it was a 3db change to double the volume. I'm doing this from memory (20+ years since college) so I'm probably off here. Can you verify? Jeff

January 8th, 2003, 09:17 PM	#24
Christopher Go Major Player Join Date: Nov 2002 Location: Honolulu, HI Posts: 429	One of the vendor links provided above was www.americanmusical.com for American Musical Supply. Anyone ever purchase one of their 'Non-factory sealed' merchandise before?

January 9th, 2003, 06:52 AM	#25
Mark Austin Regular Crew Join Date: Nov 2002 Location: Houston, Texas Posts: 188	AMS I think is the mail order wing of Guitar Center, if so I'd have no problem using them, great company. Mark __________________ I'm humbled by the greatness that surrounds me.

January 9th, 2003, 10:11 AM	#26
Rick Foxx Regular Crew Join Date: Nov 2002 Location: Tooele, UT Posts: 78	Re: AMS <<<-- Originally posted by Mark Austin : I think is the mail order wing of Guitar Center, if so I'd have no problem using them, great company. Mark -->>> Actually, Musician's Friend is the Guitar Center mail order front. AMS is (for the moment) independent. I did purchase a non-factory sealed keyboard from AMS a few years ago. It still had the full warranty, and I never had a problem with it. MIDIMan __________________ There is no problem so large that can't be solved with a suitable application of high explosives.

January 20th, 2003, 11:17 PM	#27
Christopher Go Major Player Join Date: Nov 2002 Location: Honolulu, HI Posts: 429	I think I've decided on a pair of active Tannoy Reveals. I see they're recommended here and elsewhere. Funny how in the end budgets are always doubled. Want to thank everyone for their help and input, and of course more opinions are always welcome.