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System Components: 2 speakers, 1 speaker Speaker Type: 3-way - passive -3dB Frequency Response: 35 - 20000 Hz Input Impedance: 8 Ohm Recommended Amplifier Power: 10 - 250 Watt Sensitivity: 92 dB Crossover Frequency: 3000Hz, 750Hz Output Features: Bass Reflex Magnetic Shield: Yes Connectivity Technology: Wired Detachable Grilles: Yes Additional Features: Gold-plated connectors Max (RMS) Output Power: 250 Watt Recommended Placing: Floor-standing Nominal (RMS) Output Power: 250 Watt Series: Studio NAKAMICHI RE-10 RECEIVER EXELENT!!!!! Speakers Specifications: DEF TECH BP7000 BP7000SC Key Features Speakers Function: Main / Stereo Nominal Power: 20 Watt RMS Construction: 3-Way Connectivity: Cable Technical Features Peak Power Handling: 1000 Watt Frequency Reponse: 11 Hz - 30000 kHz Sensitivity: 92 dB Impedance: 8 ohm Components Woofer Size: Midrange Size:
14" 6.5"
Tweeter Size:
1"
Design Outdoor/Indoor: Indoor Mounting: Floorstanding Exterior Color: Cheery Wood Finish Dimensions Width: Depth: Height:
8.9 in. 16.6 in. 52.5 in.
Coments: In addition, the crossover topology is improved. The original S312 tweeter had to work down to 3 kHz and all the way up to the limits of its ability. The higher-resistance L890 tweeter picks up at 5 kHz and hands off the UHF at 20 kHz to the dedicated UHF driver. That's a far easier load for the tweeter and plays to its strengths. A tweeter in the sweet spot of its range is a happy tweeter. Another change is the presence of a different 4" driver with a slightly higher resistance. The crossover asks it to run from 700 Hz to 5 kHz, and it's pretty uniform throughout that range. It has a more natural drop off near 5 kHz than the S312's 4" driver had at 3 kHz where its rising output was somewhat of a problem. Even with its 12" driver the S312 was taxed to get down to 35 Hz, and its top end was nominally 20 kHz. The L890 runs from 28 Hz to 40 kHz; though you obviously can't hear to 40 kHz (or even 20 kHz if you're my age), there's plenty of evidence that those "unhearable" frequencies have a lot to do with spatialization and presence in sound. -the strongest remaining coloration in an artisan-quality high-fidelity system can be the capacitors. I know from experience that most of the prejudice against passive crossovers in loudspeakers is actually the sound of mediocre caps in a tweeter circuit - upgrade to a top-grade part, and the sound of the crossover mostly disappears (assuming it's correctly designed in the first place) PERSONAL Recomendations:
___________________________________________________________________How To Upgrade Speakers Aug 31 '03 The Bottom Line The Shops: partsexpress.com US, wilmslowaudio.co.uk UK, madisound.com US, maplin.co.uk UK. The Forum: diyaudio.com There are three stages in which you can upgrade commercial speakers. You can
upgrade the cabinet, the drivers and the crossover, either separately or as a package. In all cases, the idea is to get better sound, without buying new speakers. Obviously we aren�t going to upgrade micro-system speakers by changing the drivers if they are made of plastic. And we aren�t going to build new cabinets for rubbish drivers. The point is, you need to have a good speaker to start with. Take for example, a simple bookshelf speaker, with a 17cm (7�) woofer and 25mm (1�) dome tweeter, that could do with better bass. The simplest solution would be to buy a subwoofer, but I bet you can get the same improvements in bass, by simply upgrading the cabinet. The box that drivers sit in can make a huge difference to the sound, as can crossovers and drivers. The solution isn�t always one stage, you may have to upgrade the crossover a little in this case too. And there isn�t anything stopping you from adding a larger woofer into a sub-cabinet � and would still cost less than a single subwoofer. You don�t need to be an experienced joiner, electrician or even good at maths. The solution can be found for free on the Internet, and you can get cabinets and crossovers built professionally. You just need to use Google to find local speaker dealers who will sell you cabinets or build crossovers for you. The key point is, you can upgrade a commercial speaker into one that will sound better than something twice what you pay to have them upgraded. In some cases, custom speakers can sound as good as commercial designs costing four times the price. If you already have speakers that sound good, then you can make them sound great. There may be something you can improve which will make them sound so much better. As in the said case, upgrading a cabinet, you can find information on using a Transmission Line system that enhances bass, much better than a larger box. The Cheap Solution If you have ever picked up a Hi Fi magazine before, you�ll have noticed the jargon about how good cables make a difference. But your speakers� internal wiring may be no better than bell-wire. This makes the internal cable re-wire the cheapest solution. It simply takes an hour to re-wire the speakers with some suitable Hi Fi cable. The difference in sound should be most noticeable in the bass. Crossovers Crossovers vary from speaker to speaker, but you will usually find the same type of components. Capacitors, Inductors, and resistors are used inside. The cheapest components are Electrolytic Capacitors, and Ferrite Core Inductors. Now these components are used mostly in the budget speakers, as they are cheap to buy. Upgrade the capacitors ones in the tweeter section to Polypropylene non-polar capacitors and the inductors in the bass section to air-core inductors and you will have a decent upgrade that is easy to notice. Note that these components are not cheap, you can expect to pay about �30/$40 for this upgrade. In a case where you know the models of the drivers, if they are labelled so you can look up information on them. You may want to see if you can improve on their performance, by either contacting a company or working it out yourself. The simplest formula uses the drivers DC impedance and a crossover figure. You can estimate a crossover frequency by comparing the drivers� frequency response, looking at where the best crossover point is for each unit. The best advice can be found on DIYaudio.com forums, if you need more information. Cabinet A good cabinet is not critical, but it is important. A weak or light built box will not be sufficient for large woofers; in some cases they can be so powerful that they rip them apart. The cabinet should be made with a wall thickness of
25mm, at least. A good cabinet will not make a very dead sound when you knock it with you hand. If you want to upgrade the cabinets, you may as well consider about the design. You don�t have to go with a rectangular box, you can be creative, copy high-end speaker designs if you want. The best part is that you can apply your own finish. Again, you can have cabinets pre-made or pre-built; some lumbar yards will cut the pieces for you. At this stage, you can also consider adding sections for additional drivers, perhaps a subwoofer. You can also add a separate enclosure for the tweeter, or supporting a heavy woofer magnet with internal bracing, or making a removable slot for a crossover. Drivers This sounds a lot easier than it is. You can�t expect two drivers to sound the same, and inserting the same sized units into your speakers could make them sound worse. Unless it�s a straight replacement, then you�ll need to adjust the crossover to suite new drivers. It doesn�t matter if its only one, you have to change the whole crossover. In some cases it can be better to upgrade one rather than the other but it depends on what you feel could be better. One of the easiest ways to find faults with your speakers is to compare them to better ones. But its even easier if the problem stands out, like harshness and distortion, which can be identified quickly. A changed crossover and tweeter for example, could reduce the harshness and also take away any distortion too. The only problem to overcome is the sizes. Most tweeters in commercial speakers come from special manufacturers like Seas, Vifa, Morel among many more, which most follow the same sizes. For example, tweeters come in circular faceplate diameters of 94, 104, 114mm, and woofers usually come in 202, 212, 222mm diameter. It�s only the unusual shaped ones that can be troublesome. What I Did My first upgrade was a Zobel network, �6/$8, which was noticeably better sounding. The second was a new tweeter, and all new crossover, �80/$112, which sounds like a new speaker, and have no more distortion � at all. My next upgrade is a subwoofer built into the lower part of the speaker, �75/$105. Conclusion Hopefully, you should understand now that commercial speakers can sound good at first, but have so much holding them back. In many cases the wiring is the worst aspect of budget speakers, which is probably the easiest and cheapest upgrade. The next culprit is the crossover; this caused distortion in my case. The strangest fact is that the cabinet is probably the best part of a speaker, so you can quite easily flush out the gubbins and get more from them.
JBL 880 Maximum Recommended Amplifier Power 200W Power Handling (Continuous/Peak) 100W/400W Nominal Impedance 8 Ohms Sensitivity (2.83V/1m) 91dB Frequency Response (�3dB) 30Hz � 40kHz
General
Crossover Frequencies 700Hz, 5kHz, 20kHz Ultrahigh-Frequency Driver 3/4" (19mm) Mylar� dome, cast-aluminum chassis, mounted in a Bi-Radial� horn High-Frequency Transducer 1" (25mm) Pure-titanium dome in JBL EOS� waveguide, cast-aluminum chassis Midrange Transducer 4" (100mm) PolyPlas� cone with rubber surround, castaluminum chassis, HeatScape� motor structure Low-Frequency Transducers Dual 6" (150mm) PolyPlas� cones with rubber surrounds, cast-aluminum chassis, HeatScape� motor structures, Symmetrical Field Geometry� (SFG�), oversized Kapton� voice coils, magnetic shorting rings Magnetically Shielded Yes Baffle Low-diffraction, IsoPower� baffle Port FreeFlow�, on front Network Straight-Line Signal Path� (SSP�) Terminals Gold-plated, 5-way binding posts, bi-wirable Dimensions (H x W x D) 39" x 8-3/4" x 14-3/4" (991mm x 222mm x 370mm) (including feet) Weight per Speaker 54 lb (24.5kg) General Cast-aluminum feet; 5/16" (8mm) floor spikes, single-packed Klipsch RF-83 frequency response: 29Hz-21kHz +/-3dB power handling: 250W RMS / 1000W Peak sensitivity: 100dB @ 2.83V / 1m nominal impedance: 8 ohms compatible high frequency drivers: 1.25" (3.2cm) Titanium diaphragm compression driver mated to 90x60 square Tractrix� Horn high freq crossover: 1650Hz
14" 6.5"
Tweeter Size:
1"
Design Outdoor/Indoor: Indoor Mounting: Floorstanding Exterior Color: Cheery Wood Finish Dimensions Width: Depth: Height:
8.9 in. 16.6 in. 52.5 in.
Coments: In addition, the crossover topology is improved. The original S312 tweeter had to work down to 3 kHz and all the way up to the limits of its ability. The higher-resistance L890 tweeter picks up at 5 kHz and hands off the UHF at 20 kHz to the dedicated UHF driver. That's a far easier load for the tweeter and plays to its strengths. A tweeter in the sweet spot of its range is a happy tweeter. Another change is the presence of a different 4" driver with a slightly higher resistance. The crossover asks it to run from 700 Hz to 5 kHz, and it's pretty uniform throughout that range. It has a more natural drop off near 5 kHz than the S312's 4" driver had at 3 kHz where its rising output was somewhat of a problem. Even with its 12" driver the S312 was taxed to get down to 35 Hz, and its top end was nominally 20 kHz. The L890 runs from 28 Hz to 40 kHz; though you obviously can't hear to 40 kHz (or even 20 kHz if you're my age), there's plenty of evidence that those "unhearable" frequencies have a lot to do with spatialization and presence in sound. -the strongest remaining coloration in an artisan-quality high-fidelity system can be the capacitors. I know from experience that most of the prejudice against passive crossovers in loudspeakers is actually the sound of mediocre caps in a tweeter circuit - upgrade to a top-grade part, and the sound of the crossover mostly disappears (assuming it's correctly designed in the first place) PERSONAL Recomendations:
___________________________________________________________________How To Upgrade Speakers Aug 31 '03 The Bottom Line The Shops: partsexpress.com US, wilmslowaudio.co.uk UK, madisound.com US, maplin.co.uk UK. The Forum: diyaudio.com There are three stages in which you can upgrade commercial speakers. You can
upgrade the cabinet, the drivers and the crossover, either separately or as a package. In all cases, the idea is to get better sound, without buying new speakers. Obviously we aren�t going to upgrade micro-system speakers by changing the drivers if they are made of plastic. And we aren�t going to build new cabinets for rubbish drivers. The point is, you need to have a good speaker to start with. Take for example, a simple bookshelf speaker, with a 17cm (7�) woofer and 25mm (1�) dome tweeter, that could do with better bass. The simplest solution would be to buy a subwoofer, but I bet you can get the same improvements in bass, by simply upgrading the cabinet. The box that drivers sit in can make a huge difference to the sound, as can crossovers and drivers. The solution isn�t always one stage, you may have to upgrade the crossover a little in this case too. And there isn�t anything stopping you from adding a larger woofer into a sub-cabinet � and would still cost less than a single subwoofer. You don�t need to be an experienced joiner, electrician or even good at maths. The solution can be found for free on the Internet, and you can get cabinets and crossovers built professionally. You just need to use Google to find local speaker dealers who will sell you cabinets or build crossovers for you. The key point is, you can upgrade a commercial speaker into one that will sound better than something twice what you pay to have them upgraded. In some cases, custom speakers can sound as good as commercial designs costing four times the price. If you already have speakers that sound good, then you can make them sound great. There may be something you can improve which will make them sound so much better. As in the said case, upgrading a cabinet, you can find information on using a Transmission Line system that enhances bass, much better than a larger box. The Cheap Solution If you have ever picked up a Hi Fi magazine before, you�ll have noticed the jargon about how good cables make a difference. But your speakers� internal wiring may be no better than bell-wire. This makes the internal cable re-wire the cheapest solution. It simply takes an hour to re-wire the speakers with some suitable Hi Fi cable. The difference in sound should be most noticeable in the bass. Crossovers Crossovers vary from speaker to speaker, but you will usually find the same type of components. Capacitors, Inductors, and resistors are used inside. The cheapest components are Electrolytic Capacitors, and Ferrite Core Inductors. Now these components are used mostly in the budget speakers, as they are cheap to buy. Upgrade the capacitors ones in the tweeter section to Polypropylene non-polar capacitors and the inductors in the bass section to air-core inductors and you will have a decent upgrade that is easy to notice. Note that these components are not cheap, you can expect to pay about �30/$40 for this upgrade. In a case where you know the models of the drivers, if they are labelled so you can look up information on them. You may want to see if you can improve on their performance, by either contacting a company or working it out yourself. The simplest formula uses the drivers DC impedance and a crossover figure. You can estimate a crossover frequency by comparing the drivers� frequency response, looking at where the best crossover point is for each unit. The best advice can be found on DIYaudio.com forums, if you need more information. Cabinet A good cabinet is not critical, but it is important. A weak or light built box will not be sufficient for large woofers; in some cases they can be so powerful that they rip them apart. The cabinet should be made with a wall thickness of
25mm, at least. A good cabinet will not make a very dead sound when you knock it with you hand. If you want to upgrade the cabinets, you may as well consider about the design. You don�t have to go with a rectangular box, you can be creative, copy high-end speaker designs if you want. The best part is that you can apply your own finish. Again, you can have cabinets pre-made or pre-built; some lumbar yards will cut the pieces for you. At this stage, you can also consider adding sections for additional drivers, perhaps a subwoofer. You can also add a separate enclosure for the tweeter, or supporting a heavy woofer magnet with internal bracing, or making a removable slot for a crossover. Drivers This sounds a lot easier than it is. You can�t expect two drivers to sound the same, and inserting the same sized units into your speakers could make them sound worse. Unless it�s a straight replacement, then you�ll need to adjust the crossover to suite new drivers. It doesn�t matter if its only one, you have to change the whole crossover. In some cases it can be better to upgrade one rather than the other but it depends on what you feel could be better. One of the easiest ways to find faults with your speakers is to compare them to better ones. But its even easier if the problem stands out, like harshness and distortion, which can be identified quickly. A changed crossover and tweeter for example, could reduce the harshness and also take away any distortion too. The only problem to overcome is the sizes. Most tweeters in commercial speakers come from special manufacturers like Seas, Vifa, Morel among many more, which most follow the same sizes. For example, tweeters come in circular faceplate diameters of 94, 104, 114mm, and woofers usually come in 202, 212, 222mm diameter. It�s only the unusual shaped ones that can be troublesome. What I Did My first upgrade was a Zobel network, �6/$8, which was noticeably better sounding. The second was a new tweeter, and all new crossover, �80/$112, which sounds like a new speaker, and have no more distortion � at all. My next upgrade is a subwoofer built into the lower part of the speaker, �75/$105. Conclusion Hopefully, you should understand now that commercial speakers can sound good at first, but have so much holding them back. In many cases the wiring is the worst aspect of budget speakers, which is probably the easiest and cheapest upgrade. The next culprit is the crossover; this caused distortion in my case. The strangest fact is that the cabinet is probably the best part of a speaker, so you can quite easily flush out the gubbins and get more from them.
JBL 880 Maximum Recommended Amplifier Power 200W Power Handling (Continuous/Peak) 100W/400W Nominal Impedance 8 Ohms Sensitivity (2.83V/1m) 91dB Frequency Response (�3dB) 30Hz � 40kHz
General
Crossover Frequencies 700Hz, 5kHz, 20kHz Ultrahigh-Frequency Driver 3/4" (19mm) Mylar� dome, cast-aluminum chassis, mounted in a Bi-Radial� horn High-Frequency Transducer 1" (25mm) Pure-titanium dome in JBL EOS� waveguide, cast-aluminum chassis Midrange Transducer 4" (100mm) PolyPlas� cone with rubber surround, castaluminum chassis, HeatScape� motor structure Low-Frequency Transducers Dual 6" (150mm) PolyPlas� cones with rubber surrounds, cast-aluminum chassis, HeatScape� motor structures, Symmetrical Field Geometry� (SFG�), oversized Kapton� voice coils, magnetic shorting rings Magnetically Shielded Yes Baffle Low-diffraction, IsoPower� baffle Port FreeFlow�, on front Network Straight-Line Signal Path� (SSP�) Terminals Gold-plated, 5-way binding posts, bi-wirable Dimensions (H x W x D) 39" x 8-3/4" x 14-3/4" (991mm x 222mm x 370mm) (including feet) Weight per Speaker 54 lb (24.5kg) General Cast-aluminum feet; 5/16" (8mm) floor spikes, single-packed Klipsch RF-83 frequency response: 29Hz-21kHz +/-3dB power handling: 250W RMS / 1000W Peak sensitivity: 100dB @ 2.83V / 1m nominal impedance: 8 ohms compatible high frequency drivers: 1.25" (3.2cm) Titanium diaphragm compression driver mated to 90x60 square Tractrix� Horn high freq crossover: 1650Hz
