It would be much easier to set benchmarks if you measure with an RTA (Real Time Analizer) like REW (freeware) so you can see what frequencies you are hearing.
Another detail: many dB meters default to "A" weighting, which reads ~ -20dB low at 100Hz, -40 at 30Hz and -50dB at 20Hz.
If your "60 dB" readings were actually 60dBA, your normal daytime video playlist music could have been well above 80 dBC, or dBZ weighted, a flat frequency response of 10Hz to 20kHz ±1.5dB.
Unweighted responses do not define the frequency range over which the meter is linear.
In the RTA example of my voice above, the level was 82.04dBZ, 81.9 dBC, 75.8dBA.
The difference between the "Slow" (1000ms up and down) "Fast" (125ms) Impulse (35ms) or Peak (maximum instantaneous level) can amount to another ~20 dB difference depending on the nature of the sound.
Art
Art, you are a gem. I adopted ARTA and picked up a Bheringer calibrated mic, but my laptop imploded under FreeCAD, and I haven't replaced it yet. Still trying to save for a new Mac Mini. My desktop PC is installed in another room in another room with as HTPC. Will order a refurbished laptop from eBay as I do need a computer in this area. At the moment I am typing to a HTPC screen 6m away in another room though large glass sliding doors
Just did some quick measurements with NIOSH for iOS the other day. You are correct, it displays 'A' weighting for frequency and 'slow' for time. Will change that and take new readings
As long as I can end up with a pair of mini towers that are very slim and not too tall and with a bass response as strong if not stronger and much cleaner than the current z623. I forgot to mention that the last graphs at 1w with a flat down to 34hz and low end rising response with 10dB boost at 42hz was a BR system tuned to 42hz and 14L driver volume. I can reclaim this space from the Cub Sandwich cab if passive radiators aren't used and if built to domestic duty
I have thought of taking a woofer and a FR from two z623 systems in my collection of 4 here and placing them in a stereo pair box as a safe bet but I dont want to live with the look of the wider resulting cab. 180mm fits on my CNC nicely and just about the max baffle width that I want to see. Everything protrudes into the smallish space
I think I have mentioned it in the past when originally discussing this driver, that this smoking/chill area is also a model for how we will furbish the cabin on our DIY houseboat (hulls are done and on trailer). This means nothing on the floor. A sound bar was the original idea but since then we had a new baby and I am moving the audio gear from what used to be our home studio into this attached room as my area
Just did some quick measurements with NIOSH for iOS the other day. You are correct, it displays 'A' weighting for frequency and 'slow' for time. Will change that and take new readings
As long as I can end up with a pair of mini towers that are very slim and not too tall and with a bass response as strong if not stronger and much cleaner than the current z623. I forgot to mention that the last graphs at 1w with a flat down to 34hz and low end rising response with 10dB boost at 42hz was a BR system tuned to 42hz and 14L driver volume. I can reclaim this space from the Cub Sandwich cab if passive radiators aren't used and if built to domestic duty
I have thought of taking a woofer and a FR from two z623 systems in my collection of 4 here and placing them in a stereo pair box as a safe bet but I dont want to live with the look of the wider resulting cab. 180mm fits on my CNC nicely and just about the max baffle width that I want to see. Everything protrudes into the smallish space
I think I have mentioned it in the past when originally discussing this driver, that this smoking/chill area is also a model for how we will furbish the cabin on our DIY houseboat (hulls are done and on trailer). This means nothing on the floor. A sound bar was the original idea but since then we had a new baby and I am moving the audio gear from what used to be our home studio into this attached room as my area
On the nautical theme, I built in 2.5 way speakers in the V berth of my (second to last..) 25 foot sailboat:
A Seas 6.5” P17 coax went in a .4 cubic foot enclosure tuned to 45 Hz, using a port 6 square inches, 12 inch deep.
A 6.5" Vifa woofer (bass assist cone), the model number which has escaped me, was in a 1 cubic foot chamber tuned to 37.5 Hz, a port 8 square inches, 11.2 inches deep.
These ports are rather large, and the area they take up is added to the box dimensions, as are the cone displacement. Fiberglass insulation was put on two sides of the interior.
The cabinets were built in to the “V” berth curves of the boat, and to achieve the correct toe-in, the speaker baffle is angled in around 45 degrees. That angle allows the cabinet to be only about 5” deep from the side wall, but because it is so thin, around 3 foot deep, tapering thinner at the back of the cabinet, which is in the forward (pointy end) of the “V” berth. I put the ports on the outside, running flush against the hull.
I built these in 1996, and at the time had never heard of Seas or Vifa, being pretty much only into pro sound. Took it all on faith from Bob Oswood that they would work well with his passive crossover design, and they did, surpassing my expectations.
I also put a third speaker near the companionway steps using another Seas P 17 Coax wired as a “phantom” speaker. This speaker is wired with the positive and negative leads going to the two positives on the amp, so only left/right difference information is reproduced out of it. With that speaker, you could hear a stereo image no matter where you sat in the cabin.
Flat to 40Hz was not bad in 1996, and the system rocked with a 30 watt per channel 12v amp.
One of the best sounding stereos I've ever heard playing everything from orchestral to punk, funk, reggae, country western, blues, jazz, new age, Americana...
Art
A Seas 6.5” P17 coax went in a .4 cubic foot enclosure tuned to 45 Hz, using a port 6 square inches, 12 inch deep.
A 6.5" Vifa woofer (bass assist cone), the model number which has escaped me, was in a 1 cubic foot chamber tuned to 37.5 Hz, a port 8 square inches, 11.2 inches deep.
These ports are rather large, and the area they take up is added to the box dimensions, as are the cone displacement. Fiberglass insulation was put on two sides of the interior.
The cabinets were built in to the “V” berth curves of the boat, and to achieve the correct toe-in, the speaker baffle is angled in around 45 degrees. That angle allows the cabinet to be only about 5” deep from the side wall, but because it is so thin, around 3 foot deep, tapering thinner at the back of the cabinet, which is in the forward (pointy end) of the “V” berth. I put the ports on the outside, running flush against the hull.
I built these in 1996, and at the time had never heard of Seas or Vifa, being pretty much only into pro sound. Took it all on faith from Bob Oswood that they would work well with his passive crossover design, and they did, surpassing my expectations.
I also put a third speaker near the companionway steps using another Seas P 17 Coax wired as a “phantom” speaker. This speaker is wired with the positive and negative leads going to the two positives on the amp, so only left/right difference information is reproduced out of it. With that speaker, you could hear a stereo image no matter where you sat in the cabin.
Flat to 40Hz was not bad in 1996, and the system rocked with a 30 watt per channel 12v amp.
One of the best sounding stereos I've ever heard playing everything from orchestral to punk, funk, reggae, country western, blues, jazz, new age, Americana...
Art
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Very nice, so much better than those marine speakers just fitted into any available flat area. Love the effort in making those cabs. Intrigued by the third speaker. Is that similar to Dolby Surround (pre Prologic)? I wonder if this would work on three points around a square deck
Fuel prices is basically forcing me away from our 3.5m sport fisher with 30hp. Not affordable a few times a week, and we live in an area with tropical fish species and love eating fish. I am also in the process of building a 3.5m unlimited daylight range type of craft. With BLDC motors, solar and lithium battery in PAS with a human power crank. I have the cat hulls in HDPE now as well as the electrics except for solar but too many projects!. This will have a some speakers too 🙂
Fuel prices is basically forcing me away from our 3.5m sport fisher with 30hp. Not affordable a few times a week, and we live in an area with tropical fish species and love eating fish. I am also in the process of building a 3.5m unlimited daylight range type of craft. With BLDC motors, solar and lithium battery in PAS with a human power crank. I have the cat hulls in HDPE now as well as the electrics except for solar but too many projects!. This will have a some speakers too 🙂
https://en.wikipedia.org/wiki/Dolby_Pro_Logic
Dolby Surround requires the audio to be encoded and decoded, the decoded channels require separate processing and amplification.
By "phantom speaker", I mean the connecting the + of a rear or side speaker to the + on one amp side ("L+"), the - to the + on the other amp side ("R+"), which results in only L/R difference information to that speaker, a kind of "triphonic" effect requiring no encoding other than the original stereo recording
A mono recording should have no L/R difference information, the "phantom speaker" (or speakers, use as many as you like in series) would be silent.
Yes, it would work, but in most places on a square deck you can hear "stereo" without the addition of the "phantom speaker".
The effect you hear from the "phantom speaker" is interesting, but may distract more than enhance.
For instance, if two mics are used to record a piano, one on the left side (lower notes) and one on the right (higher notes), and the mics hard panned L/R, with two speakers the effect is like sitting at the keyboard of a piano as large as the distance between the two speakers.
The "phantom speaker" in this case would be reproducing both mics, and the out of phase content between them which may sound weird, or plain awful- "comb filter response". Same with "leakage", if the piano player had a vocal mic panned center, much of the piano sound of either the L/R piano would again be out of phase with it, when you hear that isolated from one speaker, it can be "odd".
At any rate, you can find out a lot about how a recording was made from the "phantom speaker".