Re: I will do the experiment now Kanwar...thank you!
Hi Greg,
Thanks for your advice , It really worth a Gem....
I strongly feel that out of Band Energy ..usually Subsonic Frequencies must be filtered out steeply to get tight bass and thus greatly reduce the cone excursion...and saves the speaker..
I have implemented it today and the difference was immaculate!
A second-order High Pass Filter @ 40Hz gives the best result....
Do it Carlos and Feel the Difference!
Cheers,
K a n w a r
amplifierguru said:
Hi Greg,
Thanks for your advice , It really worth a Gem....
I strongly feel that out of Band Energy ..usually Subsonic Frequencies must be filtered out steeply to get tight bass and thus greatly reduce the cone excursion...and saves the speaker..
I have implemented it today and the difference was immaculate!
A second-order High Pass Filter @ 40Hz gives the best result....
destroyer X said:
Do it Carlos and Feel the Difference!
Cheers,
K a n w a r
Hi Kanwar,
You can take it much further by using a Q=2 HP filter which peaks 6dB - if you match this to the -6dB point of the speaker/enclosure you can actively equalise the response back to flat - resulting in a worthwhile extension to possibly 0.6Fo before. Alternately you may redesign the speaker to be smaller so extension restores the original Fo but smaller. A q=2 sallen and key filter is easy to implement with a non-inverting x2.5 op-amp and R values will be the same for tuning so you can use a DG pot and tune it to suit LF extension/peaking. The response falls of at an initial 15dB/oct and achieves -40dB at 0.1Fo. Distortion is reduced due to the reduction of out of band LF modulation.
It really decouples turntables also - I used a solid mount turntable on a bouncy suspended wood floor and you could dance on it without effect.
I designed subwoofers like this with active augmentation in 1976 but nobody wanted them then!
Cheers,
Greg 😀
You can take it much further by using a Q=2 HP filter which peaks 6dB - if you match this to the -6dB point of the speaker/enclosure you can actively equalise the response back to flat - resulting in a worthwhile extension to possibly 0.6Fo before. Alternately you may redesign the speaker to be smaller so extension restores the original Fo but smaller. A q=2 sallen and key filter is easy to implement with a non-inverting x2.5 op-amp and R values will be the same for tuning so you can use a DG pot and tune it to suit LF extension/peaking. The response falls of at an initial 15dB/oct and achieves -40dB at 0.1Fo. Distortion is reduced due to the reduction of out of band LF modulation.
It really decouples turntables also - I used a solid mount turntable on a bouncy suspended wood floor and you could dance on it without effect.
I designed subwoofers like this with active augmentation in 1976 but nobody wanted them then!
Cheers,
Greg 😀
Another Gem
Hi Greg,
I think your mindset[mood] is very good today ... giving me very good advices,... well thanks again
I would definately implement S & K filters and would post the results after that....
Cheers,
K a n w a r
Hi Greg,
I think your mindset[mood] is very good today ... giving me very good advices,... well thanks again
I would definately implement S & K filters and would post the results after that....
Cheers,
K a n w a r
Hi Guru,
The result was just a precised flow of power to the sub at 6dB peaking at 30Hz thus compensating the driver too well and the depthness in bass was still intact but with less-cone excursion..... the Gain was calibrated to 2.8 X and opamp used was OPA2134 driving 1200W pure NVMOS beast --powering up 800W Selenium in Horn loaded bass-Reflex enclosure...The performance was absoultely excellent......
Thanks for the Amendment!
K a n w a r
The result was just a precised flow of power to the sub at 6dB peaking at 30Hz thus compensating the driver too well and the depthness in bass was still intact but with less-cone excursion..... the Gain was calibrated to 2.8 X and opamp used was OPA2134 driving 1200W pure NVMOS beast --powering up 800W Selenium in Horn loaded bass-Reflex enclosure...The performance was absoultely excellent......
Thanks for the Amendment!
K a n w a r
Hi Kanwar,
Excellent, quick work good result! You may also finesse this by retuning the bass reflex port assuming it is oversize diameter you may sleeve it down 20-30% for lower cut-off. Beauty of bass reflex loading is they have a minimum excursion at around cut-off so THD in better than for sealed, but cone unloads below cut-off so HP filter is mandatory for cone control.
Cheers,
Greg
Excellent, quick work good result! You may also finesse this by retuning the bass reflex port assuming it is oversize diameter you may sleeve it down 20-30% for lower cut-off. Beauty of bass reflex loading is they have a minimum excursion at around cut-off so THD in better than for sealed, but cone unloads below cut-off so HP filter is mandatory for cone control.
Cheers,
Greg
Hi Greg,
Thanks once again,....Today is definately good for your soul....
Now , I would further analyse the enclosure, but i am afraid if it could be reduced , since all the finishing touches have been implemented already...ok I would rather do this to another box sometime may be in 2 days or so...
cheers,
K a n w a r
Thanks once again,....Today is definately good for your soul....
Now , I would further analyse the enclosure, but i am afraid if it could be reduced , since all the finishing touches have been implemented already...ok I would rather do this to another box sometime may be in 2 days or so...
cheers,
K a n w a r
Hi Kanwar,
I would always build speakers with oversize vent diameter, say, 9-10 cm then, for augmented extension, sleeve the vent with thermal lagging sponge tube which was available in a snug fit diameter and 2m lengths which could be cut to size. Then just a push in interference fit. Wall thickness around 1cm was just right.
Cheers,
greg
I would always build speakers with oversize vent diameter, say, 9-10 cm then, for augmented extension, sleeve the vent with thermal lagging sponge tube which was available in a snug fit diameter and 2m lengths which could be cut to size. Then just a push in interference fit. Wall thickness around 1cm was just right.
Cheers,
greg
Hi Greg,
Thats too good for you....
Nice interface! i would try this out and would check anything happens ...just wait a minute and i would post the result..
K a n w a r
Thats too good for you....
Nice interface! i would try this out and would check anything happens ...just wait a minute and i would post the result..
K a n w a r
Ok Greg, It turn out to be another finnesse....yet experimenting and finding the right material for tube stuff..although used heat sheet custom tube...finer improvement...thanks again...
K a n w a r
K a n w a r
You saved me from the deep ignorance kanwar, and i thank you for that.
So simple words, so easy experiment and you helped me to understand something important.
That's the reason i do not have strong positive feelings related the theorics and Mathematics guys.
They go discussing and discussing but do not help nobody, but only their selfs...saying...i know the correct thing and you do not know the correct thing.... i have read better book than you...i have studied and you do not!....i understood what Pelf Said...what Sbone told...and you misunderstood.
But not capable to produce some simple solution as you did.
Do that Carlos...and feel the difference.... ..... ready!
In my point of view, we need more guys alike you, as to diy you have real utility...you can really cooperate to our development.
thanks God that you exist, having this capacity to understand things and translate them to the ones need instructions.
Very good... experience made, result was clear.... thank you!
regards,
Carlos
So simple words, so easy experiment and you helped me to understand something important.
That's the reason i do not have strong positive feelings related the theorics and Mathematics guys.
They go discussing and discussing but do not help nobody, but only their selfs...saying...i know the correct thing and you do not know the correct thing.... i have read better book than you...i have studied and you do not!....i understood what Pelf Said...what Sbone told...and you misunderstood.
But not capable to produce some simple solution as you did.
Do that Carlos...and feel the difference.... ..... ready!
In my point of view, we need more guys alike you, as to diy you have real utility...you can really cooperate to our development.
thanks God that you exist, having this capacity to understand things and translate them to the ones need instructions.
Very good... experience made, result was clear.... thank you!
regards,
Carlos
Hi Carlos,
Thanks for the compliments...Do you checked the lesser cone movement and tightness in bass response ...
A practical approach towards solving a problem or finding a solution, is somewhat on which you can "COUNT ON US" .
An experiment is for Real and the results are always based on some Concrete Facts!
regards,
K a n w a r
Thanks for the compliments...Do you checked the lesser cone movement and tightness in bass response ...
A practical approach towards solving a problem or finding a solution, is somewhat on which you can "COUNT ON US" .
An experiment is for Real and the results are always based on some Concrete Facts!
regards,
K a n w a r
carlos-
They go discussing and discussing but do not help nobody, but only their selfs...saying...i know the correct thing and you do not know the correct thing.... i have read better book than you...i have studied and you do not!....i understood what Pelf Said...what Sbone told...and you misunderstood.
are you a designer? if not you dont know the correct thing!
mr carlos you are welcomed to say whaever you like
i am not in the business of judging, those people youve mentioned
arent perfect to be in agreement with you on the subject of subjectivism
subjectivism is there so are they, your choice who you like and who you dont
whether they help or not is a matter of who wants to learn what
"So simple words, so easy experiment and you helped me to understand something important.
That's the reason i do not have strong positive feelings related the theorics and Mathematics guys"
basicly you are all strong positive feelings related to theories of relativity
"In my point of view, we need more guys alike you, as to diy you have real utility...you can really cooperate to our development"
so do they and everyone else involved in audio
mr carlos i suggest you visit the passdiy.com there is some really good material
there, we need more guys like that dont you think?
workhorse do me a favor put up some links your site is all cooperation
critism is a bad thing after all when you receive it constructively?
what do you thing?
is critism good or bad
cheers
They go discussing and discussing but do not help nobody, but only their selfs...saying...i know the correct thing and you do not know the correct thing.... i have read better book than you...i have studied and you do not!....i understood what Pelf Said...what Sbone told...and you misunderstood.
are you a designer? if not you dont know the correct thing!
mr carlos you are welcomed to say whaever you like
i am not in the business of judging, those people youve mentioned
arent perfect to be in agreement with you on the subject of subjectivism
subjectivism is there so are they, your choice who you like and who you dont
whether they help or not is a matter of who wants to learn what
"So simple words, so easy experiment and you helped me to understand something important.
That's the reason i do not have strong positive feelings related the theorics and Mathematics guys"
basicly you are all strong positive feelings related to theories of relativity
"In my point of view, we need more guys alike you, as to diy you have real utility...you can really cooperate to our development"
so do they and everyone else involved in audio
mr carlos i suggest you visit the passdiy.com there is some really good material
there, we need more guys like that dont you think?
workhorse do me a favor put up some links your site is all cooperation
critism is a bad thing after all when you receive it constructively?
what do you thing?
is critism good or bad
cheers
Yes Mastertech, we have room to any kind of ideas, as no one of us have
so big knowledge to say the ultimate true.
I thank you by the attention, and effort to explain our small differences in ideas.
As i do not think the man can be evaluated by his ideas, but can be evaluated by his actions...actitudes, movements.... i do not care to evaluate guys because their ideas.
But i apreciate the ones have the sinthesis capacity, as i do not have, and the ones are good teachers, as kanwar..do this way...and check...ready!
Well, because of my resistance to Internet as a business, i never apreciate that, even knowing that the media has perfect capabilities to be the future main market...if not today's main market...i have never visited the forum part related Mr. Pass...as i do not apreciate a separate forum part dedicated to one Man.....even the man beeing Jesus or Muhamad, i think not adequated...and things that i do not agree...i keep distance.
Also Mr. Pass, told me that never compared his amplifier with JLH designs...well...that was too much strong to me.... since this moment he turn transparent to me...i listen without heard and i watch without see...do not accepted the informs he gave me as serious...so...facing that sittuation, i use to jump out from the relationship.
Negative to visit his site.
regards,
Carlos
so big knowledge to say the ultimate true.
I thank you by the attention, and effort to explain our small differences in ideas.
As i do not think the man can be evaluated by his ideas, but can be evaluated by his actions...actitudes, movements.... i do not care to evaluate guys because their ideas.
But i apreciate the ones have the sinthesis capacity, as i do not have, and the ones are good teachers, as kanwar..do this way...and check...ready!
Well, because of my resistance to Internet as a business, i never apreciate that, even knowing that the media has perfect capabilities to be the future main market...if not today's main market...i have never visited the forum part related Mr. Pass...as i do not apreciate a separate forum part dedicated to one Man.....even the man beeing Jesus or Muhamad, i think not adequated...and things that i do not agree...i keep distance.
Also Mr. Pass, told me that never compared his amplifier with JLH designs...well...that was too much strong to me.... since this moment he turn transparent to me...i listen without heard and i watch without see...do not accepted the informs he gave me as serious...so...facing that sittuation, i use to jump out from the relationship.
Negative to visit his site.
regards,
Carlos
Upupa Epops said:
There is much that is flawed with this topology....
For a start, contrary to intuition, the second stage does not operate remotely like a differential amp....
....and the much-vaunted push-pull action often assumed to occur at its output does not occur in fact...
Hi !
I made some realworld-measurements...
Obviously my right channel has some defect ?
Hum is present, but is below -80db, and not audible.
But, i can't tell if these results are good or bad...
See yourself:
http://www.lf-pro.net/mbittner/rmaa/Symasym5_1.htm
The measuring is in fact only 24bits, but rmaa seems a bit buggy,
showing better results on 32bits than on 24bits...
Mike
I made some realworld-measurements...
Obviously my right channel has some defect ?
Hum is present, but is below -80db, and not audible.
But, i can't tell if these results are good or bad...
See yourself:
http://www.lf-pro.net/mbittner/rmaa/Symasym5_1.htm
The measuring is in fact only 24bits, but rmaa seems a bit buggy,
showing better results on 32bits than on 24bits...
Mike
MikeB said:
when did they start to measure "spendid" in db and fft curves?
I mean, if an amp is guarantted to sound great (putting aside if such a guarantor was ever able or willing enough to back his words up), shouldn't we need to judge the amp based on its sound not just measurements?
I was almost convinced by AKSA yesterday that there is a negative correleation between fabulous measurements and good sound.
Hello Mikeks, good to see your wife picture again...and to have your visit.
Glúteus máximus was excelent philosopher, not all guys understand it's deepness...hehe
Depending how clever the guys is...alike dear Mikeks, things can jump from strange to funny...you already asked your brazilian friends SY, the coincidence of this philosopher name....hehe...accident.
Carlos
Glúteus máximus was excelent philosopher, not all guys understand it's deepness...hehe
Depending how clever the guys is...alike dear Mikeks, things can jump from strange to funny...you already asked your brazilian friends SY, the coincidence of this philosopher name....hehe...accident.
Carlos
MikeB said:
Seems to be an aweful lot of 4, 5 & 6 + higher harmonics here -- i would say that it is undeserving of a very good rating. The right channel is also shelved up >1kHz -- i'd guess that is a noise issue.
dave
Michael, we already made all tests, and amplifier worked very good, sounding nice.
The ones that have doubts will have sure about your design quality constructing it.
So, let them construct if they want, really, to know.
As theories discussion will never finish.... try to remenber that less than 500 years ago, they used to banish people that had the idea that the world was not squared.
The navigators gone and found that earth was not squared.
They still remain having doubts...they will be, now a days, still discussing those things, if they could be alive so long.
Mikeks is someone that understand deeply the theories, and he is famous to produce and maintain those never ending discussions.
I suggest you to let the ones that have doubt to construct, and showing us that really did the construction in real world, so, they can return to produce some evaluation based on reality.
This is the same that someone that never drive a Mercedez start to have doubts about its confort, and search for theories because having wells touching the road cannot have smooth movement.
So, i strongly suggest you to wait the ones that are producing the Symassym to evaluate it's performance.
Well, Mikeks is a respectable guy, also Planet 10...but there are others that really are not more than noise related to good communication.
And never fear, Charlie is here...the amplifier is guaranteed!
regards,
Carlos
The ones that have doubts will have sure about your design quality constructing it.
So, let them construct if they want, really, to know.
As theories discussion will never finish.... try to remenber that less than 500 years ago, they used to banish people that had the idea that the world was not squared.
The navigators gone and found that earth was not squared.
They still remain having doubts...they will be, now a days, still discussing those things, if they could be alive so long.
Mikeks is someone that understand deeply the theories, and he is famous to produce and maintain those never ending discussions.
I suggest you to let the ones that have doubt to construct, and showing us that really did the construction in real world, so, they can return to produce some evaluation based on reality.
This is the same that someone that never drive a Mercedez start to have doubts about its confort, and search for theories because having wells touching the road cannot have smooth movement.
So, i strongly suggest you to wait the ones that are producing the Symassym to evaluate it's performance.
Well, Mikeks is a respectable guy, also Planet 10...but there are others that really are not more than noise related to good communication.
And never fear, Charlie is here...the amplifier is guaranteed!
regards,
Carlos