The word is spreading...
My girlfriend is coming tomorrow. She has never seen or heard (of) it.. Wonder if she likes the Symef
I will be waiting
Best for 2Ohms
Hello Harrison,
I have been following with some interest as I am looking to replace my 4 stereo power amps with some Hypex Ncore in the near future.
A few technical points make choice of power amps interesting.
My new line array speakers are fully active 3 ways with full DSP ( LiPo battery powered DEQX digital with 6 channels of Buffalo 11 DAC's) linear phase crossovers. They are 109dB for 1 watt at 1 meter between 80Hz and 2KHz, 2Ohms ( can be 4 Ohms at 103 dB if required) and 110 dB for 1 watt at one meter above 2KHz and 3 Ohms.
The bass is 99dB 1 watt / 1 meter 8 Ohms.
Do you have boards available that are stable into a 2 Ohm midrange and 3 Ohm high frequency range? I only require 100 watts into these loads.
All my power amps are LiPo battery powered. I have access to very low cost LiPo batteries and chargers via my " day job" hence I have 6 battery packs 30Kg each) in situ with up to plus/minus 90 volts ( can get any voltage required) and enough current to throw a 100 Kg man across a large room!
The bass is an easy load but would be better with 200watts or more as its a 15 inch pro driver that can take 600watts AES with only 2.7dB power compression.
Thanks in advance and all the best
Derek.
Hello Harrison,
I have been following with some interest as I am looking to replace my 4 stereo power amps with some Hypex Ncore in the near future.
A few technical points make choice of power amps interesting.
My new line array speakers are fully active 3 ways with full DSP ( LiPo battery powered DEQX digital with 6 channels of Buffalo 11 DAC's) linear phase crossovers. They are 109dB for 1 watt at 1 meter between 80Hz and 2KHz, 2Ohms ( can be 4 Ohms at 103 dB if required) and 110 dB for 1 watt at one meter above 2KHz and 3 Ohms.
The bass is 99dB 1 watt / 1 meter 8 Ohms.
Do you have boards available that are stable into a 2 Ohm midrange and 3 Ohm high frequency range? I only require 100 watts into these loads.
All my power amps are LiPo battery powered. I have access to very low cost LiPo batteries and chargers via my " day job" hence I have 6 battery packs 30Kg each) in situ with up to plus/minus 90 volts ( can get any voltage required) and enough current to throw a 100 Kg man across a large room!
The bass is an easy load but would be better with 200watts or more as its a 15 inch pro driver that can take 600watts AES with only 2.7dB power compression.
Thanks in advance and all the best
Derek.
could you tell us more about obtaining that very high efficiency/sensitivity?
Symef amps
Hello Harrison,
Thanks for your reply and PM.
I will join the group buy and I am delighted that your amps are stable into 2 Ohms.
Stability into low impedance is vital, for me it is every bit as important as the headline specs of distortion spectrum, broad power bandwidth, high slew rate etc.
Solid state amplifiers (class A, AB and D ) and DSP ( DAC's, Eq, crossovers, filters & limiters) are now so advanced they leave the poor old loudspeaker looking ( and sounding) very much like last centuries technology.
I believe loudspeakers are the weakest link, by some margin.
The loudspeaker power amplifier interface is the key to reducing the errors and compromises in all loudspeakers.
See next post to answer Andrews question and please forgive the slight off topic into loudspeaker design, but it is all very closely linked to your Symef amps ability to drive low impedance loads.
Thanks and all the best
Derek.
Hello Harrison,
Thanks for your reply and PM.
I will join the group buy and I am delighted that your amps are stable into 2 Ohms.
Stability into low impedance is vital, for me it is every bit as important as the headline specs of distortion spectrum, broad power bandwidth, high slew rate etc.
Solid state amplifiers (class A, AB and D ) and DSP ( DAC's, Eq, crossovers, filters & limiters) are now so advanced they leave the poor old loudspeaker looking ( and sounding) very much like last centuries technology.
I believe loudspeakers are the weakest link, by some margin.
The loudspeaker power amplifier interface is the key to reducing the errors and compromises in all loudspeakers.
See next post to answer Andrews question and please forgive the slight off topic into loudspeaker design, but it is all very closely linked to your Symef amps ability to drive low impedance loads.
Thanks and all the best
Derek.
High efficiency / low impedance speakers for Symef
Hi Andrew,
Never mind the Germans of Scandinavians, its the Scots ( I am an Ayrshire lad ) who really like everything to be as efficient as possible!
As this is a Symef thread I don’t want to ramble on ( who me?!) too much...Summary of my line array theory and goals.
(1) All drivers sound and measure exactly the same...When they are not working! Only as you feed in tiny signals will they start to produce sounds, and as the signal level rises to a minimal level we can start to hear and measure the differences. Interestingly I have found my ears are able to identify different drivers and sonic signatures way before the measurements can...
(2) MINIMISE CONE / DIAGHPHRAM MOVEMENT AT ALL COSTS!! This is why big ugly horns with Pro compression drivers can ( if done correctly ) sound so good in low SPL domestic situations...The driver diaphragms are hardly moving at all.
(3) This minimises the inherent time distortion of delayed energy storage / energy release as the cones / domes / ribbons etc. oscillate after being energised. How long they bounce around on their suspensions all depends on their settling times AND how much energy they are trying to dissipate i.e. how much energy was pumped in in order to hit the required SPL... This all depends on the efficiency... Voila!
So in my pursuit of highest efficiency I have ended up with line array's and separate subs.
Attached is an 8 driver line array using 4 Ohm BMR's with 90dB @1 watt. Parallel 4 drivers for a 1 Ohm load and you get a 12dB ( theoretical) gain in sensitivity, I measure only 10dB to 11dB increase. Then series wire the two groups of four drivers for a 2 Ohm load. You now have reduced cone movement by a factor of 8 compared to a single driver. It gets even better moving to 16 drivers in a 4 Ohm configuration, same 101dB sensitivity but you reduce cone movement by another 50% and have an easier load for the amp (even SET's can cope with this!)
My ultimate iteration is a fully active 3 way DSP controlled, genuine 111dB for 1 watt from 80Hz up to 20KHz system.
I am keeping it under wraps at the moment as I may start selling it commercially next year, but I would do a group buy / DIY launch first to test the water!
It uses 8 rather special 16 Ohm AMT drivers I have OEM'd to my spec, all parallel wired for a flat 2 Ohm load. They measure flat to 400Hz mounted in a slim teardrop shaped column but sound best crossed over at around 1Khz to an array of 8 eight inch cone drivers (16 Ohms each) I have again OEM'd. They are flat to 80Hz and 100dB / 1 watt per driver, so with parallel wiring you gain 12dB and drop to 2Ohms.
The max AES CONTINUOUS SPL of the arrays is over 128dB with ZERO thermal compression... Short term SPL peaks are beyond ears or SPL meter...
Subs are 15 inch Pro drivers in 100 litres sealed box, 99dB for 1 watt, max AES power is 600 watts so they can pump out around 126dB bass all day and all night.
A pair each side ( 4 drivers in total) can be parallel of course for 105dB and over 130dB SPL for festival use...!
The point is at sane domestic levels in any size of room they melt your heart with music, music, music, all the gear and technical stuff flies out the window and you sit there and smile, laugh, cry, or get up dance as the music dictates....
My speaker journey is over!!
Now all I need is the best possible power amps ( I don’t use a pre-amp) to complete me...Hello Harrison??!!
All the best
Derek.
PS Again, sorry about the OT ramble.
Hi Andrew,
Never mind the Germans of Scandinavians, its the Scots ( I am an Ayrshire lad ) who really like everything to be as efficient as possible!
As this is a Symef thread I don’t want to ramble on ( who me?!) too much...Summary of my line array theory and goals.
(1) All drivers sound and measure exactly the same...When they are not working! Only as you feed in tiny signals will they start to produce sounds, and as the signal level rises to a minimal level we can start to hear and measure the differences. Interestingly I have found my ears are able to identify different drivers and sonic signatures way before the measurements can...
(2) MINIMISE CONE / DIAGHPHRAM MOVEMENT AT ALL COSTS!! This is why big ugly horns with Pro compression drivers can ( if done correctly ) sound so good in low SPL domestic situations...The driver diaphragms are hardly moving at all.
(3) This minimises the inherent time distortion of delayed energy storage / energy release as the cones / domes / ribbons etc. oscillate after being energised. How long they bounce around on their suspensions all depends on their settling times AND how much energy they are trying to dissipate i.e. how much energy was pumped in in order to hit the required SPL... This all depends on the efficiency... Voila!
So in my pursuit of highest efficiency I have ended up with line array's and separate subs.
Attached is an 8 driver line array using 4 Ohm BMR's with 90dB @1 watt. Parallel 4 drivers for a 1 Ohm load and you get a 12dB ( theoretical) gain in sensitivity, I measure only 10dB to 11dB increase. Then series wire the two groups of four drivers for a 2 Ohm load. You now have reduced cone movement by a factor of 8 compared to a single driver. It gets even better moving to 16 drivers in a 4 Ohm configuration, same 101dB sensitivity but you reduce cone movement by another 50% and have an easier load for the amp (even SET's can cope with this!)
My ultimate iteration is a fully active 3 way DSP controlled, genuine 111dB for 1 watt from 80Hz up to 20KHz system.
I am keeping it under wraps at the moment as I may start selling it commercially next year, but I would do a group buy / DIY launch first to test the water!
It uses 8 rather special 16 Ohm AMT drivers I have OEM'd to my spec, all parallel wired for a flat 2 Ohm load. They measure flat to 400Hz mounted in a slim teardrop shaped column but sound best crossed over at around 1Khz to an array of 8 eight inch cone drivers (16 Ohms each) I have again OEM'd. They are flat to 80Hz and 100dB / 1 watt per driver, so with parallel wiring you gain 12dB and drop to 2Ohms.
The max AES CONTINUOUS SPL of the arrays is over 128dB with ZERO thermal compression... Short term SPL peaks are beyond ears or SPL meter...
Subs are 15 inch Pro drivers in 100 litres sealed box, 99dB for 1 watt, max AES power is 600 watts so they can pump out around 126dB bass all day and all night.
A pair each side ( 4 drivers in total) can be parallel of course for 105dB and over 130dB SPL for festival use...!
The point is at sane domestic levels in any size of room they melt your heart with music, music, music, all the gear and technical stuff flies out the window and you sit there and smile, laugh, cry, or get up dance as the music dictates....
My speaker journey is over!!
Now all I need is the best possible power amps ( I don’t use a pre-amp) to complete me...Hello Harrison??!!
All the best
Derek.
PS Again, sorry about the OT ramble.
Attachments
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Which link for group buy
Harrison,
In the group buy section you have several group buy links...which is the best one for me?
My speakers are 3 way fully active ( 6 mono block channels) and I see you have a two boards per person limit...I need 6 channels for my speakers, is that ok with you?
Also worth mentioning I run everything from source to speakers fully balanced, can your design run fully balanced?
Lastly, the amps will be powered from LiPo battery packs not mains transformers, does this have any side effects to watch out for?
The amps will be fixed directly to the 8mm thick alloy back panel of the speakers and ( seperate) subs, approx 330mm tall by 250mm (110 square inches) wide per channel . Will this suffice for heatsinking remebering my 2Ohm and 3 Ohm loads and 100 watt per channel reqiremnts.
Thanks again and all the best
Derek.
Harrison,
In the group buy section you have several group buy links...which is the best one for me?
My speakers are 3 way fully active ( 6 mono block channels) and I see you have a two boards per person limit...I need 6 channels for my speakers, is that ok with you?
Also worth mentioning I run everything from source to speakers fully balanced, can your design run fully balanced?
Lastly, the amps will be powered from LiPo battery packs not mains transformers, does this have any side effects to watch out for?
The amps will be fixed directly to the 8mm thick alloy back panel of the speakers and ( seperate) subs, approx 330mm tall by 250mm (110 square inches) wide per channel . Will this suffice for heatsinking remebering my 2Ohm and 3 Ohm loads and 100 watt per channel reqiremnts.
Thanks again and all the best
Derek.
Derek, I am humbled. This is a tough call, the heart of a man loves this thing now and the other thing later. Yes the SYMEF will do 100watts 2Ohm, you can ensure this by using lower rail voltages. Now you have my palms all sweaty and my pulse is racing. Ooh the heart of man, who can please it. However will attempt to please ears. Ears that can pickup discrepancy before the meters do. Yes we need you
As I normally do will try to get more free PCBs. But if I dont get the grant we will have to rely on donations from members, really as a donating member what cant you get ? No limit really
.
Hi Derek,
Were you thinking about something close to this .
Run a higher line signal to get a better signal to noise ratio then use R23 as a potentiometer to create a balance between your active speakers and attenuate the line signal to the right level
Were you thinking about something close to this
.Run a higher line signal to get a better signal to noise ratio then use R23 as a potentiometer to create a balance between your active speakers and attenuate the line signal to the right level
Attachments
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Integrating into balanced tri amped active system
Hi Harrison,
Thanks, I am happy to try whatever configuration you think is best.
I think there are a lot of music lovers out there who will benefit from your design.
The iPod age has created a demand for small high quality music & video systems...Slim is in...TV's, on wall speakers, low profile electronics...
If the SYMEF amp can bring small format & affordable high end amplification to well designed active speakers you will make a lot of friends...!
A lap top or dedicated PC running J River media and JPlay plug-in makes a great source.
Next in line is the DSP crossover / room Eq, feed that into a good DAC and feed that into the back of your loudspeakers with two or three onboard SYMEF amps and you are done...!
Looking forward to the next few months build and test.
Cheers
D.
Hi Harrison,
Thanks, I am happy to try whatever configuration you think is best.
I think there are a lot of music lovers out there who will benefit from your design.
The iPod age has created a demand for small high quality music & video systems...Slim is in...TV's, on wall speakers, low profile electronics...
If the SYMEF amp can bring small format & affordable high end amplification to well designed active speakers you will make a lot of friends...!
A lap top or dedicated PC running J River media and JPlay plug-in makes a great source.
Next in line is the DSP crossover / room Eq, feed that into a good DAC and feed that into the back of your loudspeakers with two or three onboard SYMEF amps and you are done...!
Looking forward to the next few months build and test.
Cheers
D.
Hi Derek, thank you, you may have two options
1. Run analog to speakers
2. Run digital to speakers
Talk to the DAC and analog line threads they may have something that you may need
The type 2 PCB measures 4*3.5
Low profile electronics love class D due to low heat
Looking forward to your build, now where are those PCBs
1. Run analog to speakers
2. Run digital to speakers
Talk to the DAC and analog line threads they may have something that you may need
The type 2 PCB measures 4*3.5
Low profile electronics love class D due to low heat
Looking forward to your build, now where are those PCBs
The word is spreading...
My girlfriend is coming tomorrow. She has never seen or heard (of) it.. Wonder if she likes the Symef
............ kindly continue with the story
Hope Bambadoo still has a girlfriend, and maybe she did not want to listen to music.......
Why, do you think she's disappointed with Bambadoo's taste?
