I am suprised at what little content the car audio section has
Does no one do there own installs, make there own boxes, cabling etc?
All there seems to be is a small discussion on PSUs for car amps and a load of newbie questions
Anyway I thought Id share pics of my install as it progresses. I have just purchased an A31 cefiro with no stereo and I have a collection of equipment to install in it
Pics to come.....
Does no one do there own installs, make there own boxes, cabling etc?
All there seems to be is a small discussion on PSUs for car amps and a load of newbie questions
Anyway I thought Id share pics of my install as it progresses. I have just purchased an A31 cefiro with no stereo and I have a collection of equipment to install in it
Pics to come.....
This is the car, a 1989 Nissan Cefiro:
The first thing that needed changing was the parcel tray as it had already been hackup up to fit 6x9" speakers which I did not want:
I made one out of two sheets of MDF:
And speaker spacers out of MDF:
This is where I am heading and I have almost completed it:
An externally hosted image should be here but it was not working when we last tested it.
The first thing that needed changing was the parcel tray as it had already been hackup up to fit 6x9" speakers which I did not want:
An externally hosted image should be here but it was not working when we last tested it.
I made one out of two sheets of MDF:
An externally hosted image should be here but it was not working when we last tested it.
And speaker spacers out of MDF:
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
This is where I am heading and I have almost completed it:
An externally hosted image should be here but it was not working when we last tested it.
Ok, just did a little drawing .....
That´s the setup in my winter-car , a Subaru station wagon 4x4 (2.0l turbo , 200hp).
I used to run the subs with a GenX zeus , which is now resting until I got my car for the summer ready. In the V4004 for the subs I installed more and bigger capacitors in the SMPS.
That´s the setup in my winter-car , a Subaru station wagon 4x4 (2.0l turbo , 200hp).
I used to run the subs with a GenX zeus , which is now resting until I got my car for the summer ready. In the V4004 for the subs I installed more and bigger capacitors in the SMPS.
An externally hosted image should be here but it was not working when we last tested it.
Hi
Yes, caps will always help
The big 1F caps will increase the voltage delivered to the amplifier when the engine is running, thus makes it easier for the DC-converter to convert more power. Also the draw of electrical current is way faster done by a cap than a battery. That´s why the caps should always be installed as nearest as possible to the amplifiers. If there is more than 50cm cable between cap and amp , the cap is useless.
A friend of mine did some testing with a 1kw digital amplifier running with caps and w/o caps and I wouldn´t run high-current amplifiers without a cap.
What I did was also encrease the capacity of the caps that are on the secondary side of the DC-converter, that also helps as the subs draw a lot of current, it´s rather useless when driving smaller speakers, as their current draw is smaller.
Yes, caps will always help
The big 1F caps will increase the voltage delivered to the amplifier when the engine is running, thus makes it easier for the DC-converter to convert more power. Also the draw of electrical current is way faster done by a cap than a battery. That´s why the caps should always be installed as nearest as possible to the amplifiers. If there is more than 50cm cable between cap and amp , the cap is useless.
A friend of mine did some testing with a 1kw digital amplifier running with caps and w/o caps and I wouldn´t run high-current amplifiers without a cap.
What I did was also encrease the capacity of the caps that are on the secondary side of the DC-converter, that also helps as the subs draw a lot of current, it´s rather useless when driving smaller speakers, as their current draw is smaller.
sdoom said:Yes, caps will always help
The big 1F caps will increase the voltage delivered to the amplifier when the engine is running, thus makes it easier for the DC-converter to convert more power. Also the draw of electrical current is way faster done by a cap than a battery. That´s why the caps should always be installed as nearest as possible to the amplifiers. If there is more than 50cm cable between cap and amp , the cap is useless.
A friend of mine did some testing with a 1kw digital amplifier running with caps and w/o caps and I wouldn´t run high-current amplifiers without a cap.
A capacitor CANT increase voltage.
Well, like I said before its highly debated. People seem think "my lights stop dimming once I added a capacitor so it must be better" but I think a capacitor is more of a bandaid for a inadequate electrical system. I have noticed that most of the people who have advanced knowledge of electricity, ESR etc think they are a marketing ploy and most of the people who think they are good have lesser knowledge. I dont think you can say they are better in every situation, I think maybe there are few situation when they are better but thats just my oppinion
When you are faced with an electrical problem where you might add a capacitor, its not a debate between adding a cap or not, its a debate as to wether to add a capacitor or spend that money on a battery and alternator upgrade instead.
Here is some discussion:
http://forums.beyond.ca/showthread.php?s=&threadid=44291
http://forums.beyond.ca/showthread/t-48038.html
Technical arguements:
http://www.realcaraudio.com/forums/showthread.php?s=&threadid=42570&highlight=capacitor
sdoom said:
How do you do that?
caps...
Hi,
sdoom is right about increasing the caps on the output of the DC-DC converter, but this is not for the beginner. The caps need to be of the correct spec or they will die fast and probably take the rest of the amp with them...small, high temp, high quality caps are not necessarily trivial to find and not cheap...
The output of the DC-DC converter is normally a high freq squareish wave, somewhere between +/- 20 and 50v depending on the power of the amp. The cap must be designed for constant, deep, high freq charge / discharge cycles, with low internal losses or it will generate heat and ultimately 'pop', I'd only consider 105c caps.
That having been said caps on the output side of the smps are probably 10 times more effective than those on the input, basically because they are holding more power through much higher voltage, they charge and discharge with less losses because the currents are lower, and they tend to be of higher quality, for the reasons described earlier.
I am still studying the 'profile' of current draw from the amps I've been repairing, but it is already clear that some are very brutal on the input side, having current peaks that are very high relative to the average. If this is a common problem then the 'huge' caps, placed very, very close to the amp are probably fulfilling demand for these peaks, and making the cabling up to that point 'see' a smoother demand. They don't make the nominal voltage higher, but I would hypothesize that they make the nominal current through the main cables closer to the true average, and as such are probably useful.
Stuart
Hi,
sdoom is right about increasing the caps on the output of the DC-DC converter, but this is not for the beginner. The caps need to be of the correct spec or they will die fast and probably take the rest of the amp with them...small, high temp, high quality caps are not necessarily trivial to find and not cheap...
The output of the DC-DC converter is normally a high freq squareish wave, somewhere between +/- 20 and 50v depending on the power of the amp. The cap must be designed for constant, deep, high freq charge / discharge cycles, with low internal losses or it will generate heat and ultimately 'pop', I'd only consider 105c caps.
That having been said caps on the output side of the smps are probably 10 times more effective than those on the input, basically because they are holding more power through much higher voltage, they charge and discharge with less losses because the currents are lower, and they tend to be of higher quality, for the reasons described earlier.
I am still studying the 'profile' of current draw from the amps I've been repairing, but it is already clear that some are very brutal on the input side, having current peaks that are very high relative to the average. If this is a common problem then the 'huge' caps, placed very, very close to the amp are probably fulfilling demand for these peaks, and making the cabling up to that point 'see' a smoother demand. They don't make the nominal voltage higher, but I would hypothesize that they make the nominal current through the main cables closer to the true average, and as such are probably useful.
Stuart
MAXW,
Their are alot of us here with systems in our auto`s.
Myself at the moment I`m building one for my old full-size bronco.It will consist of 6 fiberglass speaker boxes and 4 `glass pods.The subs will be mounted in 2-3.5cft ported boxes,the mid bass will be 4-.75cft sealed boxes,the midrange and tweets will be in 4 pods.I have a pioneer head,an old Orion parametric 5 band eq,a caver crossover with holographic and bass retrieval,an old ppi art sires to handle power for the mid range and highs,orion 800.4 for the mid bass,another orion 800.4 to power the subs,a 200 amp alt. and deep cycle battery just for the system and my driving(8) lights,winch,etc...,0 gauge wire to the 3f cap..Driver consist of 2 sets of 6.5 polk db components,4 mtx 8"mtx for midbass,2-12 eclipse alum's.
And before anyone jumps me about so much midbass,your going to have to understand how and what I use this truck for.My wife and I do alot of offroading,we drive the truck to nearby offroad parks most with in a 2hour drive.The tires are quite large 40" tall and 16" wide with very large lugs.Most of the time I have the top off.
But what seems to happen the tire noise cancels out the lower midrange,so I`m trying to overcome that.Now whether this works or not I`m not sure but I think that it is worth a try.
Their are alot of us here with systems in our auto`s.
Myself at the moment I`m building one for my old full-size bronco.It will consist of 6 fiberglass speaker boxes and 4 `glass pods.The subs will be mounted in 2-3.5cft ported boxes,the mid bass will be 4-.75cft sealed boxes,the midrange and tweets will be in 4 pods.I have a pioneer head,an old Orion parametric 5 band eq,a caver crossover with holographic and bass retrieval,an old ppi art sires to handle power for the mid range and highs,orion 800.4 for the mid bass,another orion 800.4 to power the subs,a 200 amp alt. and deep cycle battery just for the system and my driving(8) lights,winch,etc...,0 gauge wire to the 3f cap..Driver consist of 2 sets of 6.5 polk db components,4 mtx 8"mtx for midbass,2-12 eclipse alum's.
And before anyone jumps me about so much midbass,your going to have to understand how and what I use this truck for.My wife and I do alot of offroading,we drive the truck to nearby offroad parks most with in a 2hour drive.The tires are quite large 40" tall and 16" wide with very large lugs.Most of the time I have the top off.
But what seems to happen the tire noise cancels out the lower midrange,so I`m trying to overcome that.Now whether this works or not I`m not sure but I think that it is worth a try.
Hi
sorry ´bout my English, I hope I can make myself understandable. I said, if the engine is running, the capacitor helps getting a higher voltage .
The generator -voltage is higher than the battery voltage, otherwise we couldn´t charge the car´s battery , which actually is no battery, it is a accumulator ( meaning a rechargable battery).
If you take a look at the generator´s voltage, it is not flat, it ´s more like a wave. the big capcitors mounted near the amplifier will charge up to the maximum voltage of that wave , (as simple as a normal rectifing unit placed after a 110V transformer) . Thus giving most amplifiers the ability to produce highe output power as the amplifiers DC-converter will run more effective on higher input voltage. E.g. Hifonics Zeus (series 8) has a variopower DC-converter, the manual says that input voltage doesn´t matter.........well in all tests with those amplifiers they delivered more output power running @15V than they did running at 12V .....
A car battery is not able to charge that fast !
Also the big capacitor is faster than a battery . If placed very close to the amplifiers it will always have a postivie effect, regardless if you use a second battery, bigger alternators or other stuff.
We did a couple of tests with a 1kW- Digiamp inside the car running sinewaves and Musik from a Test-CD , with and without 2x1F capacitors. We monitored the voltage and current draw (via a shunt) and the Caps really flatend the voltage at any current draw.
I agree that the CAP is discharged very fast, too, but it also charges much much faster than the battery does. So an additional / bigger alternator and/or battery help very much to run the 12V-System more stable at high and steady current flow, but for the peaks a capacitor is essential. Again, this only works out if cables (from amp to cap) are thick and short, otherwise the principle of the cap doesn´t work.
______________________________________
The reason why to upgrade the capacitors in the SMPS was said already. most of the times, capacitors in a SMPS are not high-quality. Most car amplifiers are mass-products and the manuf. want to make big money, that´s another reason why most of this stuff is made in China and Korea.
the capcitors in a SMPS on the input side usually have 105°C and lower ESR (Ripple current is higher on the input side) compared to the secondary side capacitors (85°C , regular cap).
As the SMPS runs square signals through the transformer (its closer to square tahn to sine) and at much higher frequency (aroun 20-50kHz depending on the layout) , the time were no voltage produced by the transformer is very short, therefore caps usually are small on the secondary side of the smps. But again, more capacity is more helpfull than less. In the Crunch, there are only 2x3300µF , and I thought for pure subwoofer use that could be a bit more (as I run the amplifier in 2x bridge mode). I used capacitors from a broken amplifier, Low-ESR and 105° and because there was enough room on the curcuit board I installed 8x2200µF . This will keep the output voltage of the DC converter more stable under higher current drains.
sorry ´bout my English, I hope I can make myself understandable. I said, if the engine is running, the capacitor helps getting a higher voltage .
The generator -voltage is higher than the battery voltage, otherwise we couldn´t charge the car´s battery , which actually is no battery, it is a accumulator ( meaning a rechargable battery).
If you take a look at the generator´s voltage, it is not flat, it ´s more like a wave. the big capcitors mounted near the amplifier will charge up to the maximum voltage of that wave , (as simple as a normal rectifing unit placed after a 110V transformer) . Thus giving most amplifiers the ability to produce highe output power as the amplifiers DC-converter will run more effective on higher input voltage. E.g. Hifonics Zeus (series 8) has a variopower DC-converter, the manual says that input voltage doesn´t matter.........well in all tests with those amplifiers they delivered more output power running @15V than they did running at 12V .....
A car battery is not able to charge that fast !
Also the big capacitor is faster than a battery . If placed very close to the amplifiers it will always have a postivie effect, regardless if you use a second battery, bigger alternators or other stuff.
We did a couple of tests with a 1kW- Digiamp inside the car running sinewaves and Musik from a Test-CD , with and without 2x1F capacitors. We monitored the voltage and current draw (via a shunt) and the Caps really flatend the voltage at any current draw.
I agree that the CAP is discharged very fast, too, but it also charges much much faster than the battery does. So an additional / bigger alternator and/or battery help very much to run the 12V-System more stable at high and steady current flow, but for the peaks a capacitor is essential. Again, this only works out if cables (from amp to cap) are thick and short, otherwise the principle of the cap doesn´t work.
______________________________________
The reason why to upgrade the capacitors in the SMPS was said already. most of the times, capacitors in a SMPS are not high-quality. Most car amplifiers are mass-products and the manuf. want to make big money, that´s another reason why most of this stuff is made in China and Korea.
the capcitors in a SMPS on the input side usually have 105°C and lower ESR (Ripple current is higher on the input side) compared to the secondary side capacitors (85°C , regular cap).
As the SMPS runs square signals through the transformer (its closer to square tahn to sine) and at much higher frequency (aroun 20-50kHz depending on the layout) , the time were no voltage produced by the transformer is very short, therefore caps usually are small on the secondary side of the smps. But again, more capacity is more helpfull than less. In the Crunch, there are only 2x3300µF , and I thought for pure subwoofer use that could be a bit more (as I run the amplifier in 2x bridge mode). I used capacitors from a broken amplifier, Low-ESR and 105° and because there was enough room on the curcuit board I installed 8x2200µF . This will keep the output voltage of the DC converter more stable under higher current drains.
I am going to steer clear of the capacitor debate
Finshed Parcel tray
...and started sub enclosure
....for this sub:
http://www.imagesubs.co.nz/products/ls12x.asp
Finshed Parcel tray
An externally hosted image should be here but it was not working when we last tested it.
...and started sub enclosure
An externally hosted image should be here but it was not working when we last tested it.
....for this sub:
http://www.imagesubs.co.nz/products/ls12x.asp
An externally hosted image should be here but it was not working when we last tested it.
nice shelf
...I have always gone to great lengths to maintain a more stealthy mode of install, I don't want someone to be inspired to try and rip-off my stuff...
I have a lot of car audio, a lot of recently fixed amps, but I'm embarrassed to admit most of it is not installed.
On the finished list: I have a pair of GMC typhoons, small SUVs, that have Infinity Reference 6x4, 2 way, plate speakers up front, driven by Pioneer head units (DEH85 I think), the rear speakers are KEF Kar and Infinity Reference, 6x9, 2 way, driven by a SoundStream Reference 200 (high power mode). All the way at the back, mounted in the tailgate I have a pair of Onkyo auto subs, 6x9's with a PP xmax of 12mm, and 2 ohms VCs. These are driven from bridged SoundStream SA80s, fed by a 4 into 1 crossover.
For the most part the capacitor debate is pretty easy, if you've used one and like the result, you have your answer.
Technically speaking, I am 'viewing' the results of running an amp at full power. The way current is drawn is not 'steady', nor is it wholely a function of the audio signal being played, so peoples analysis where they assume the caps are working on a DC supply, modulated by the music are much too simplistic. The supply side is more complex than the output side, so any technical evaluation had better show me more a little more depth than the normal ones I've seen. The SMPS is running at anything from a few tens of kHz to a few hundred, and it draws current on this 'schedule'. At these frequencies, the cables feeding the amps have a more significant impedance, and also measurable skin effect. So someone telling about DC currents and averages will only convince me the person hasn't actually thought about or measured the problem...
Stuart
...I have always gone to great lengths to maintain a more stealthy mode of install, I don't want someone to be inspired to try and rip-off my stuff...
I have a lot of car audio, a lot of recently fixed amps, but I'm embarrassed to admit most of it is not installed.
On the finished list: I have a pair of GMC typhoons, small SUVs, that have Infinity Reference 6x4, 2 way, plate speakers up front, driven by Pioneer head units (DEH85 I think), the rear speakers are KEF Kar and Infinity Reference, 6x9, 2 way, driven by a SoundStream Reference 200 (high power mode). All the way at the back, mounted in the tailgate I have a pair of Onkyo auto subs, 6x9's with a PP xmax of 12mm, and 2 ohms VCs. These are driven from bridged SoundStream SA80s, fed by a 4 into 1 crossover.
For the most part the capacitor debate is pretty easy, if you've used one and like the result, you have your answer.
Technically speaking, I am 'viewing' the results of running an amp at full power. The way current is drawn is not 'steady', nor is it wholely a function of the audio signal being played, so peoples analysis where they assume the caps are working on a DC supply, modulated by the music are much too simplistic. The supply side is more complex than the output side, so any technical evaluation had better show me more a little more depth than the normal ones I've seen. The SMPS is running at anything from a few tens of kHz to a few hundred, and it draws current on this 'schedule'. At these frequencies, the cables feeding the amps have a more significant impedance, and also measurable skin effect. So someone telling about DC currents and averages will only convince me the person hasn't actually thought about or measured the problem...
Stuart
Re: nice shelf
I have no doubt whatsoever that a stiffening cap is a good thing to have on an amp. It won't make up for an inadequate electrical system, nor is is panacea for all evils of car audio, but it's a good thing nonetheless.
I think of amplifier current draw as being something akin to the air intake into an engine. There are a lot of parallels there. An engine doesn't take a smooth flow of air in, it takes it in small gulps as the intake valves open. So too, and amplifier takes current according to its demand. From some standpoints, it makes sense to just measure the average flow on a volume (coulombs) over time basis, however, there are large variations from moment to moment. A capacitor helps convert these fluctuations into a steady flow, which the battery and electrical system are better equiped to provide.
You've got that right. This is also the reason that I have a good alarm system installed (Which my neighbors will hopefully never hear) and I always turn the volume down whenever I'm near home.Stuart Easson said:
Hmmm... Most of the things I see people talk about caps for is to prevent fading lights. In this case, averages do work... Against you.Stuart Easson said:
I have no doubt whatsoever that a stiffening cap is a good thing to have on an amp. It won't make up for an inadequate electrical system, nor is is panacea for all evils of car audio, but it's a good thing nonetheless.
I think of amplifier current draw as being something akin to the air intake into an engine. There are a lot of parallels there. An engine doesn't take a smooth flow of air in, it takes it in small gulps as the intake valves open. So too, and amplifier takes current according to its demand. From some standpoints, it makes sense to just measure the average flow on a volume (coulombs) over time basis, however, there are large variations from moment to moment. A capacitor helps convert these fluctuations into a steady flow, which the battery and electrical system are better equiped to provide.
for instance
Hi,
lilduff, the RMS rating for a speaker is the amount of power the speaker can be driven with, continuously before failing. *Ideally* it is derived from a few things, minimally the maximum heat power the voicecoil (VC) of the speaker can stand, and the maximum low freq physical excursion the cone, VC and spider can stand. Most car speaker manufacturers completely ignore the excursion limits, basically because it depends on freq and enclosure, and then they ridiculously overrate the thermal capability.
For some guidelines, If you look at the physical specs and the driver has a 1" voice coil, a 'good' VC has a thermal power rating that is around 35w, there are cases above and below, but this is a realistic start. There is no way it can be 200w, or any other random, huge number their marketing dept came up with, it is physically impossible. As the diameter increases, so does the surface area of the windings, and the amount of heat the VC can dissipate. But it increases as the square of the diameter, so other things being equal a 2" VC can cope with 150w, a 3" VC gets into the hundreds. Long term there will be other factors that contribute, all that heat has to go somewhere, the speaker frame will begin to heat up and eventually the power has to get into the open air. If your speakers are trapped in a very small space, they will again begin to overheat after max power for long periods...the VC glue will fail or the the expansion of the copper windings will distort the former too far and the VC will rub against the magnet assembly, perhaps shorting out in the process.
Hope that helps
Stuart
Hi,
lilduff, the RMS rating for a speaker is the amount of power the speaker can be driven with, continuously before failing. *Ideally* it is derived from a few things, minimally the maximum heat power the voicecoil (VC) of the speaker can stand, and the maximum low freq physical excursion the cone, VC and spider can stand. Most car speaker manufacturers completely ignore the excursion limits, basically because it depends on freq and enclosure, and then they ridiculously overrate the thermal capability.
For some guidelines, If you look at the physical specs and the driver has a 1" voice coil, a 'good' VC has a thermal power rating that is around 35w, there are cases above and below, but this is a realistic start. There is no way it can be 200w, or any other random, huge number their marketing dept came up with, it is physically impossible. As the diameter increases, so does the surface area of the windings, and the amount of heat the VC can dissipate. But it increases as the square of the diameter, so other things being equal a 2" VC can cope with 150w, a 3" VC gets into the hundreds. Long term there will be other factors that contribute, all that heat has to go somewhere, the speaker frame will begin to heat up and eventually the power has to get into the open air. If your speakers are trapped in a very small space, they will again begin to overheat after max power for long periods...the VC glue will fail or the the expansion of the copper windings will distort the former too far and the VC will rub against the magnet assembly, perhaps shorting out in the process.
Hope that helps
Stuart
i have a pile of crap going in my truck 1 of these days. for now its all sitting in my bedroom collecting dust.
Alpine CDA-9833
Audio Control Overdrive line driver
Audio Control 24XS xover
Audio Control EQL
Vifa 7" PL18WO's
LPG 25NFA's
Image Dynamics ID10
Arc Audio 4050 CXL
Arc Audio 2500 CXL
i have a Tru Technology T-4.65 i may use instead of the 4050. havent decided yet.
Alpine CDA-9833
Audio Control Overdrive line driver
Audio Control 24XS xover
Audio Control EQL
Vifa 7" PL18WO's
LPG 25NFA's
Image Dynamics ID10
Arc Audio 4050 CXL
Arc Audio 2500 CXL
i have a Tru Technology T-4.65 i may use instead of the 4050. havent decided yet.
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