old guys, old drivers and old ways

[mobile_bob]

maybe the title is too obscure? or maybe i might hit a chord with someone here.

count one, old guy: check that box, at nearly 64 i guess i qualify

count two: old drivers, check that box as i can't seem to bring myself to throwing out old drivers, and i got lots of them

count three: old ways, guilty as charged, i guess the way i was brought up, not having much and having to creatively use stuff (junk).

back when i was young, late 60's and early 70's in a small midwest town, where there was little to work with, even less money, and lots of time
some of us spent countless hours, reading and researching all manner of what interested us, and then we would march out to the scrap yard
or whereever to procure the needed material to build what we needed... sometimes the result was a miserable failure, and sometime it was a fantastic success.

nothing like winning your first drag race with a 5 dollar basket case cushman scooter, up against a perfectly maintained matching '59 cushman husky
to forever twist a young mind into believing he could do just about anything with not so much money, if he did the research, put in the effort and with a dash of luck.

of course i got older, went off and made my way in the world, found out there was real money to be made, and found i could simply go out and buy pretty much anything
i wanted.... to which several new cars, big houses, and all the other crap for ex-wives, and their atty's... but where is the fun in that?

i see lots of folks building diy speaker kits, and diy amplifiers, etc. however

i also see more than a few asking about going it alone, only to be told "awe heck you should start out with a kit" or some such.

what is wrong with building and failing? seems like through failure there is a gain? at least i can eliminate that path as one that didn't work?

and what about all the ancillary stuff that is learned along the way, how to use tools, what materials are available, how they are to work with, are but a few.

then we learn what we don't know, and go back to the books, or internet to learn more.

i am thinking that every dang one of the famous speaker builders started out in his garage, or his dad's, and make a few flops to begin with?
i am unaware of a single university that has a major in speaker design, so it isn't something that is taught? or can you get a degree and go to work building speakers?

maybe the goal should be learning all one can, design and build, maybe with cheap materials and first, then progress, with the end goal being something that suits the visual
and audio palate of the builder? and who the hell cares if the "audiophile" community thinks it merits a look or listen?

currently i have what i would call a mid-fi system, a direct drive sansui turntable, a denon pma-920 amp, and a pair of jbl 150a speakers, certainly not top end, but not your typical
lunch box crap they sell at wally world either.

my latest project was a set of 4 speakers, labyrinth, back loaded, using 8 speakers taken from mid 60's akai tape decks, 5x7 oval paper with alnico magnets, probably, a buck each back
in the day. i sat down and laid out a design for a back loaded labyrinth with an 82" line. put two speaker in parallel, one on top of the other, ending in a 4" round port, poly filled, double layer side walls or 1/4" plywood, bonded with non hardening adhesive. i built one such unit, brought it in and tested it.... sounded pretty good, but was missing under about 200hz.... i then learned i had over stuffed the thing with polyfil and reduced the packing to a light fill, brought back and got it down to 100 hz. (as low as my puter can put out on the sound card), put it back in place of one of the jbl speakers to get a feel and i thought hmmmm pretty good indeed.

so i built another, and tested the pair, sound was very encouraging, so i built the other two, and then set about altering the fill in each to retest and see which came out on top, it worked out to be the second iteration of the first speaker cab, so i did them all the same, finished the glue up and put the four together, two in series to get 8 ohms per side and fired up dark side of the moon.

to say that i am happy with the result is an understatement, i would be proud to enter them in a diy contest, i don't think i would rank at the top, but my bet is i wouldn't be at the bottom either

the design visually is my take on japanese architectural design. and i used a silver maple that i had sawn up about 5 years ago, for the top and trim work, nice tiger stripe

why did i build these?

because in '75 i bought a sanyo 8 track quadraphonic player for my car, it being a discrete 4 channel forever changed me when i first heard dark side of the moon in quad.

so all these years later i found three of the same FT864 sanyo players, on ebay, and bought each as they came up, thinking i could make one out of three.

first one i tried, works flawlessly, no nasty noise from the pots, great sound from each channel, who would have thought a nearly 50 y/o player would work at all much less
flawlessly.

so now i am on the hunt for dark side of the moon in Q8

so there is my introductory story and i am sticking to it!

back to moody blues in Q8

bob g
ps. i still need to rub them out and apply several coats of lacquer (i can't help it, i am an old guy and i like lacquer), and i am going to change the grill cloth to a deep burgundy so i don't have the three tone thing going on.
[

 

[TLS Guy]

maybe the title is too obscure? or maybe i might hit a chord with someone here.

count one, old guy: check that box, at nearly 64 i guess i qualify

count two: old drivers, check that box as i can't seem to bring myself to throwing out old drivers, and i got lots of them

count three: old ways, guilty as charged, i guess the way i was brought up, not having much and having to creatively use stuff (junk).

back when i was young, late 60's and early 70's in a small midwest town, where there was little to work with, even less money, and lots of time
some of us spent countless hours, reading and researching all manner of what interested us, and then we would march out to the scrap yard
or whereever to procure the needed material to build what we needed... sometimes the result was a miserable failure, and sometime it was a fantastic success.

nothing like winning your first drag race with a 5 dollar basket case cushman scooter, up against a perfectly maintained matching '59 cushman husky
to forever twist a young mind into believing he could do just about anything with not so much money, if he did the research, put in the effort and with a dash of luck.

of course i got older, went off and made my way in the world, found out there was real money to be made, and found i could simply go out and buy pretty much anything
i wanted.... to which several new cars, big houses, and all the other crap for ex-wives, and their atty's... but where is the fun in that?

i see lots of folks building diy speaker kits, and diy amplifiers, etc. however

i also see more than a few asking about going it alone, only to be told "awe heck you should start out with a kit" or some such.

what is wrong with building and failing? seems like through failure there is a gain? at least i can eliminate that path as one that didn't work?

and what about all the ancillary stuff that is learned along the way, how to use tools, what materials are available, how they are to work with, are but a few.

then we learn what we don't know, and go back to the books, or internet to learn more.

i am thinking that every dang one of the famous speaker builders started out in his garage, or his dad's, and make a few flops to begin with?
i am unaware of a single university that has a major in speaker design, so it isn't something that is taught? or can you get a degree and go to work building speakers?

maybe the goal should be learning all one can, design and build, maybe with cheap materials and first, then progress, with the end goal being something that suits the visual
and audio palate of the builder? and who the hell cares if the "audiophile" community thinks it merits a look or listen?

currently i have what i would call a mid-fi system, a direct drive sansui turntable, a denon pma-920 amp, and a pair of jbl 150a speakers, certainly not top end, but not your typical
lunch box crap they sell at wally world either.

my latest project was a set of 4 speakers, labyrinth, back loaded, using 8 speakers taken from mid 60's akai tape decks, 5x7 oval paper with alnico magnets, probably, a buck each back
in the day. i sat down and laid out a design for a back loaded labyrinth with an 82" line. put two speaker in parallel, one on top of the other, ending in a 4" round port, poly filled, double layer side walls or 1/4" plywood, bonded with non hardening adhesive. i built one such unit, brought it in and tested it.... sounded pretty good, but was missing under about 200hz.... i then learned i had over stuffed the thing with polyfil and reduced the packing to a light fill, brought back and got it down to 100 hz. (as low as my puter can put out on the sound card), put it back in place of one of the jbl speakers to get a feel and i thought hmmmm pretty good indeed.

so i built another, and tested the pair, sound was very encouraging, so i built the other two, and then set about altering the fill in each to retest and see which came out on top, it worked out to be the second iteration of the first speaker cab, so i did them all the same, finished the glue up and put the four together, two in series to get 8 ohms per side and fired up dark side of the moon.

to say that i am happy with the result is an understatement, i would be proud to enter them in a diy contest, i don't think i would rank at the top, but my bet is i wouldn't be at the bottom either

the design visually is my take on japanese architectural design. and i used a silver maple that i had sawn up about 5 years ago, for the top and trim work, nice tiger stripe

why did i build these?

because in '75 i bought a sanyo 8 track quadraphonic player for my car, it being a discrete 4 channel forever changed me when i first heard dark side of the moon in quad.

so all these years later i found three of the same FT864 sanyo players, on ebay, and bought each as they came up, thinking i could make one out of three.

first one i tried, works flawlessly, no nasty noise from the pots, great sound from each channel, who would have thought a nearly 50 y/o player would work at all much less
flawlessly.

so now i am on the hunt for dark side of the moon in Q8

so there is my introductory story and i am sticking to it!

back to moody blues in Q8

bob gView attachment 34864
ps. i still need to rub them out and apply several coats of lacquer (i can't help it, i am an old guy and i like lacquer), and i am going to change the grill cloth to a deep burgundy so i don't have the three tone thing going on.
[

No wonder you have had more wives than hot dinners!

 

[mobile_bob]

No wonder you have had more wives than hot dinners!

hey thanks for that! put a smile on my face to start the day!

perchance me thinks i am on the wrong forum?

bob g

 

[KEW]

hey thanks for that! put a smile on my face to start the day!

perchance me thinks i am on the wrong forum?

bob g

Maybe...

I enjoyed your story and am glad to see the end result brought you joy.

From a DIY standpoint this site is more about helping people design their DIY speakers than a trial and error approach.
I'm glad you got reasonable sound quality out of your DIY project and get a kick out of 4-channel 8 track being your source; however, I believe you would be better served learning from others rather than reinventing what has been well developed science of speaker design.
You mentioned majoring in speaker design not being an option, however, there are lots of resources (including the expertise of experienced designers here) to help you learn and optimize your speakers. There are some good books on speaker design to be had as well!
TLSGuy above is one of those who is willing to advise and help people learn (although his experience as a doctor may reduce his participation as the CoronaVirus situation gets dire).
Check out the link in his signature to see his system w/his DIY speakers!

 

[Pogre]

i also see more than a few asking about going it alone, only to be told "awe heck you should start out with a kit" or some such.

what is wrong with building and failing? seems like through failure there is a gain? at least i can eliminate that path as one that didn't work?

and what about all the ancillary stuff that is learned along the way, how to use tools, what materials are available, how they are to work with, are but a few.

then we learn what we don't know, and go back to the books, or internet to learn more.

i am thinking that every dang one of the famous speaker builders started out in his garage, or his dad's, and make a few flops to begin with?
i am unaware of a single university that has a major in speaker design, so it isn't something that is taught? or can you get a degree and go to work building speakers?

maybe the goal should be learning all one can, design and build, maybe with cheap materials and first, then progress, with the end goal being something that suits the visual
and audio palate of the builder? and who the hell cares if the "audiophile" community thinks it merits a look or listen?

A lot of those speaker builders who started in their garage also have a plethora of information online so you can learn from their mistakes. Don't you think cutting your teeth on a proven design would be a good learning experience?

 

[mobile_bob]

you guys make good points and i appreciate them all

i am thinking that maybe my point has been missed.

if one were to have limited time, limited abilities, resources, materials, tools etc... then yes starting with a kit
might well be the best of all directions to take... a proven design will certainly have a much higher likelihood of success... and for far less money and time being spent.

i can't argue that point.

i guess maybe a different analogy would be useful

say you guys are all into hotrods,

now we all can go buy a 32 ford 5 window coupe kit, and we can all go buy the parts to put together a small block 350 chevy, and stick a turbo 350 behind it, and in the end have a reliable and driveable car, probably for a reasonable amount of money and time spent assembling it.

now if that is where it ends, that being something that satisfies our own needs then fine, all is good
if however you go to a rod run, and see 50 more just like yours, save for maybe 50 different colors, then hmm maybe something is missing?

i recall vividly about 15 years ago, going to a goodguys show in puyallup washington, there were probably 500 cars, with the majority being trailer queens, built from a list of over the counter cookie cutter parts, and yes they were all beautiful, however

the star of the show was a post war roadster, built by two kids in nevada iirc, it was a hodpodge of all sorts of stuff, looked to be welded together with bailing wire and a torch, headers for the old buick engine were fabricated from old iron bed frames, and it ran, and reportedly was found in a barn after nearly 50 years sitting there. you would not believe the amount of attention that beater got that day.

this might be a stretch to use as an example, as i am not supporting the idea of just throwing together a bunch of crap into an old wood crate and call it a low-fi, let alone mid or hi-fi speaker.

my point in not so many words? there ought to be some sort of middle ground?

try as i might i have never seen anything written on the reuse of of vintage drivers in new designs, this might be because of several issues, not the least of which is unknown parameters and/or the lack of equipment and ability to determine them.

my use of the likely very cheap 5x7 akai speakers was not because i couldn't afford better, or don't have better to work with, rather it was simply an exercise of experiment to try to apply what i have spent a number of years reading about.

my personal technical library is probably within the upper 1% and i am constantly on the lookout for more on a variety of subjects.

as for hot meals? i do 99% of the cooking around here, and have for decades, i don't miss many meals.

my hope is to find a group of folks that are into learning from doing, working with repurposed drivers, in interesting designs, even if a small one. i thought maybe there might be a few here with similar interests, as the question has been brought up more than once on this forum.

enough of all that...

my next project, the reuse of 4 sansui 12" woofers, that i replaced the petrified cloth surrounds with foam on, i am thinking two per cabinet, in a MTM configuration, using two 3" full range to cover the upper end, driven by biamp via SET tube. back and front loaded.

ducking for cover now


bob g

 

[lovinthehd]

Do you measure your results or is it all by ear?

 

[mobile_bob]

currently no i do not measure the results, as the source material being 50 y/o 8 track would be laughably bad
by any measure.

for me i use the old standard, if the damn thing wears me out, then it is not acceptable
if on the other hand i can sit and listed for hours? then it is acceptable.

do i have "golden" ears? no i don't but they are the best i have to work with
and i can tell anyone this much they are good enough to tell the difference between "remastered" crap lp's being sold today, against the originals in many cases, even if the old stuff has pops and clicks, most of it doesn't wear me out, like the last several lp's i have spent money on.

a speaker that hides this "remastered" crap is not a good speaker to me, a good speaker to my ears bring out the best of the good and the worst of the bad.

and if my speakers turn out to be revealing in that regard, then i think i am the right track...

is however some day i feel the need to get others approval of the sound, or enter a competition, maybe then i would pony up and get some stuff to measure them with, but then there is this...

from what i read the room the speaker is setup in is as important a part of the total system as any other part, and i think most have seen several hundred thousand dollar systems setup in horrible environments, where there is no way anyone but the owner could stand to sit through one side of an lp, no matter how good the lp was?

so in all sincerity and respect

what would i be measuring? unless i am prepared to live in an anechoic chamber, where the goal might be a perfectly flat response, being played back in a perfectly flat room? or what?

i am here to learn, guys
don't think for a moment that i am trying to stir things up.

allow me to digress a bit...

i haven't gotten to my most interested question yet... that being the dark side of the moon immersion set
where apparently there is the allan parsons 4.0 quad mix on disc 3? what i would like to know is what specifically is needed to play that disc? apart from 4 speakers, whether they be diy, kit or off the shelf units?

up until i discovered this offering, the only way to hear dark side in quad was on 8 track tape, with all its limitations, at least as it was originally mixed by parsons?

you guys are a patient lot

thanks
bob g

 

[lovinthehd]

LOL was thinking you didn't measure but thought I'd ask. What do you do for crossovers? Measuring would perhaps give you some insight as to your preference if anything.

As to the multich DSotM disc is dvd or bluray or SACD? In any case you can't play it with your current gear. You'd need a dvd/bluray/sacd player (some can do all formats, tho) and an avr with multich capabilities.

 

[Pogre]

you guys make good points and i appreciate them all

i am thinking that maybe my point has been missed.

if one were to have limited time, limited abilities, resources, materials, tools etc... then yes starting with a kit
might well be the best of all directions to take... a proven design will certainly have a much higher likelihood of success... and for far less money and time being spent.

i can't argue that point.

i guess maybe a different analogy would be useful

say you guys are all into hotrods,

now we all can go buy a 32 ford 5 window coupe kit, and we can all go buy the parts to put together a small block 350 chevy, and stick a turbo 350 behind it, and in the end have a reliable and driveable car, probably for a reasonable amount of money and time spent assembling it.

now if that is where it ends, that being something that satisfies our own needs then fine, all is good
if however you go to a rod run, and see 50 more just like yours, save for maybe 50 different colors, then hmm maybe something is missing?

i recall vividly about 15 years ago, going to a goodguys show in puyallup washington, there were probably 500 cars, with the majority being trailer queens, built from a list of over the counter cookie cutter parts, and yes they were all beautiful, however

the star of the show was a post war roadster, built by two kids in nevada iirc, it was a hodpodge of all sorts of stuff, looked to be welded together with bailing wire and a torch, headers for the old buick engine were fabricated from old iron bed frames, and it ran, and reportedly was found in a barn after nearly 50 years sitting there. you would not believe the amount of attention that beater got that day.

this might be a stretch to use as an example, as i am not supporting the idea of just throwing together a bunch of crap into an old wood crate and call it a low-fi, let alone mid or hi-fi speaker.

my point in not so many words? there ought to be some sort of middle ground?

try as i might i have never seen anything written on the reuse of of vintage drivers in new designs, this might be because of several issues, not the least of which is unknown parameters and/or the lack of equipment and ability to determine them.

my use of the likely very cheap 5x7 akai speakers was not because i couldn't afford better, or don't have better to work with, rather it was simply an exercise of experiment to try to apply what i have spent a number of years reading about.

my personal technical library is probably within the upper 1% and i am constantly on the lookout for more on a variety of subjects.

as for hot meals? i do 99% of the cooking around here, and have for decades, i don't miss many meals.

my hope is to find a group of folks that are into learning from doing, working with repurposed drivers, in interesting designs, even if a small one. i thought maybe there might be a few here with similar interests, as the question has been brought up more than once on this forum.

enough of all that...

my next project, the reuse of 4 sansui 12" woofers, that i replaced the petrified cloth surrounds with foam on, i am thinking two per cabinet, in a MTM configuration, using two 3" full range to cover the upper end, driven by biamp via SET tube. back and front loaded.

ducking for cover now


bob g

I don't think I'm missing your point. You like doing it the hard way!

Me, I'd rather do a little bit of homework, work smarter and not harder and try to do it right the first time. Even then I'm sure there would still be some mistakes made that I would learn from.

 

[mobile_bob]

LOL was thinking you didn't measure but thought I'd ask. What do you do for crossovers? Measuring would perhaps give you some insight as to your preference if anything.

As to the multich DSotM disc is dvd or bluray or SACD? In any case you can't play it with your current gear. You'd need a dvd/bluray/sacd player (some can do all formats, tho) and an avr with multich capabilities.

glad i hit your funny bone!

i guess if the ladies don't find you handy, they ought to at least find you entertaining, maybe that goes for menfolk too?

for the current units, they need no crossover, running full range
the base is not big, but it is there, is tight and i can hear individual notes, no single boom tone
the mid range is in my mind about perfect,
the high's have enough air, and as stated earlier, i can't hear over about 9.5khz anymore anyway

for the next project, a crossover will be needed, and i want to keep it simple if possible, with a first order
the 12" sansui's go up much further than i would have ever thought, well over 5khz but i see no need to go that high, the tweets are faital 3" and have a reportedly pretty flat response from around 200 up to way over my hearing

i have the equipment and wire, formers etc to wind my own coils, so plan on some work to get something that works for me.... again if i like it and see the need, maybe then i will invest in some test gear. until then "kiss" is the rule around here.

as for the immersion set, dark side, i think disk 3 is a dvd, might be a scad? not sure

could i use a scad player and feed it into something like a denon 5.1 avr and get the 4 channels out?

can a scad player do dvd's seems like it would, but hey i am a decade or three behind the times.

thanks
bob g

 

[lovinthehd]

as for the immersion set, dark side, i think disk 3 is a dvd, might be a scad? not sure

could i use a scad player and feed it into something like a denon 5.1 avr and get the 4 channels out?

can a scad player do dvd's seems like it would, but hey i am a decade or three behind the times.

thanks
bob g

IIRC there's more than one variation on the immersion set. https://www.discogs.com/Pink-Floyd-The-Dark-Side-Of-The-Moon-Immersion-Box-Set/release/3137117

The optical disc player will specify what formats it can play, some are more universal than others, so check the manual of the SACD player (that it can do multich SACD...or dvd....or bluray). A Denon 5.1 avr would be able to handle the multich audio, yes.

 

[mobile_bob]

IIRC there's more than one variation on the immersion set. https://www.discogs.com/Pink-Floyd-The-Dark-Side-Of-The-Moon-Immersion-Box-Set/release/3137117

The optical disc player will specify what formats it can play, some are more universal than others, so check the manual of the SACD player (that it can do multich SACD...or dvd....or bluray). A Denon 5.1 avr would be able to handle the multich audio, yes.

thank you for that!
bob g

 

[mobile_bob]

I don't think I'm missing your point. You like doing it the hard way!

Me, I'd rather do a little bit of homework, work smarter and not harder and try to do it right the first time. Even then I'm sure there would still be some mistakes made that I would learn from.

i will accept part of your assessment as being possible, that part being "doing it the hard way", mainly because you know nothing about me personally, apart from what you glean from a few words posted here... so fair enough in that regard.

as for the rest, "doing a bit of homework", "working smarter and not harder", and "trying to do it right the first time" makes some rather broad assumptions at least in my opinion.
1. i have been reading everything i can get my hands on for well over 50 years now, and have stacks of books, periodicals going back to 1980 speaker builder, popular mechanics going back to the "sweet sixteen" of the early 60's, and hours upon hours of reading everything google can present to me.

2. i have been afflicted by a severe case of scoliosis since the age of 13, spent several years in a milwakee brace (a certain kind of hell) and then later against doctor recommendations went into heavy mechanical repair business, so i am no newbie to working smarter not harder, i made a science of it for the 40 years i was doing all that... i had to as my back would allow me to do it one time, and one time only without paying dearly for sometimes weeks on end.

3. as for "doing it right the first time" who really sets out to do it wrong the first time? i think most save for a few that are masochist maybe?

the goal was to set out and apply what i had learned, using drivers i had, which are as stated all but worthless when new and certainly didn't improve with age i am sure. anyone who has been around a mid 60's akai rtr deck or similar knows what i am saying as low-fi is probably giving them a benefit of the doubt... apparently there were meant only as a way of monitoring what was recorded, to check and see if you actually did record something to be played back later on external speakers of significantly better quality.

the point being boils down to in my way of thinking at least, there is something to be gained by building one such unit, to test theory, and to see if a 50cent speaker really has to sound like crap? or can it be improved? if it can be, then one might expect similar result using better drivers? if however the result was worse? who would want to report on using drivers many times more expensive? to have crap sounding result?

the exercise is really no different than that done by at least mass marketed speaker manufactures, wherein they keep working on designs to improve the system so that they can use 50 cent speakers and assure profitability for their stock holders and keep their jobs... they seem to think it a worthwhile endeavor.

maybe that is not a direct correlation, but it is a close cousin? don't you think?

for what i have in 4 speakers, dollar wise, and the amount of time spent building them, with the result being something that is enjoyable to listen to, at least to me is a home run. i think i have a bit less than 35 dollars per unit in materials invested, and my time of course. i write off my time as entertainment and continued education.

i don't mean to be harsh, so please don't take offense.

and thanks to all who have added to the conversation here, i really appreciate everyone's time.

bob g

 

[Pogre]

the exercise is really no different than that done by at least mass marketed speaker manufactures, wherein they keep working on designs to improve the system so that they can use 50 cent speakers and assure profitability for their stock holders and keep their jobs... they seem to think it a worthwhile endeavor.

Some companies use the scientific process to improve on their speakers, not cheapen them. Those are the companies I tend to buy from. As far as a worthwhile endeavor, yes. When you have all of the resources, testing equipment and decades (combined, centuries) of experience, anechoic chambers for testing and know how it's a little bit different from cobbling together some cheap, mismatched parts, crossing your fingers and hoping for the best. There are tried and true methods proven to work (or not work, which is where you seem dismissive) and building a speaker is a very well understood science.

i don't mean to be harsh, so please don't take offense.

None taken. I don't think you're being harsh at all.

 

[ski2xblack]

Enjoy the hobby however you like.

FWIW, I see no problem using a SET to drive mids or tweets in an active rig, they work very well for that. However, if you're using passive crossovers the high source impedance can do unexpected things, such as introducing out of band spikes. Just food for thought.

 

[mobile_bob]

Enjoy the hobby however you like.

FWIW, I see no problem using a SET to drive mids or tweets in an active rig, they work very well for that. However, if you're using passive crossovers the high source impedance can do unexpected things, such as introducing out of band spikes. Just food for thought.

thanks for that, my thinking was to include a separate subwoofer to support the bottom end, and try to keep the main cabinet as a two way so that the crossover might be a bit easier to accommodate. i have used two small stereo tube set amps, split so that the left channel goes through one amp, and each of its channels split to do the mid and tweet, and same for the other channel... it takes a bit of tweaking but the results a pretty good using first order crossovers, however i would really like to build into each channel of the left and also the right amps so that i could do an active crossover that could be adjustable, sort of like a simplified equalizer?

edit: just wanted to add this, the little tube stereo amps i am using have separate volume controls for each channel and also separate tone controls, so i can balance differing db levels between drivers to some extent.

drive the sub with a class D amp, maybe off a 5.1 amplifier

more to learn for sure!

thanks
bob g

 

[adwilk]

I enjoyed reading your story and anecdotal approach to what brings you joy in the hobby. Nothing wrong with that at all. I like the handiwork and passion. Its inspiring.

Most here are interested in the pursuit of perfection- the science, the math, the design, the application etc. An endeavor that (intentionally or not) doesn't employ those things won't typically be received well.

 

[mobile_bob]

I enjoyed reading your story and anecdotal approach to what brings you joy in the hobby. Nothing wrong with that at all. I like the handiwork and passion. Its inspiring.

Most here are interested in the pursuit of perfection- the science, the math, the design, the application etc. An endeavor that (intentionally or not) doesn't employ those things won't typically be received well.

i kind of gathered that is the case!

and believe me i too can get into the weeds with theory, math, science, etc... its been a while, but at one time internet handle "mobile_bob" if presented to google would return more than most ever wanted to read when it came to the technical. however it wasn't related to audio.

but thanks for the heads up...

now back to the group

the question was posited, "do you measure?"

i have been giving this some thought, and i have a couple or three questions

1. what would i measure? smiles per hour of listening? seriously...
i left the forum with the thought of taking it to heart and giving the question of "measurement" some serious thought, and i came up with more questions than i did answers... i have a tone generator, a scope, voltmeter, amp meter and am not afraid of buying spectrum analyzers, software, or whatever is needed, however when i read the things i am left with are the following

a. it would appear that speaker design and building certainly has accelerated over the last 40 years or so, leaving one to think that surely by now most if not all speakers offered for sale would be "neutral" or all sound exactly the same playing the same souce, in the same room, and they certainly do not! every speaker sold today yesterday , today, and likely tomorrow will sound a bit different than all the others.

b. i recently watched a youtube wherein the presenter was talking about his collection of lp pressings of dark side of the moon, i think he might have had 27 different ones (i don' think i am exaggerating but it is possible i am off a few give or take). his report or take was they all sounded different from one another, some closer than other, some really poor some middle of the road, 3 very good in his opinion. so we have to accept that the source material is variable to say the least, and the perfect speaker is not going to do anything but bring out those differences moreso?

c. if we were to go to a live performance of a symphony in carnegie hall, and listen to them play a piece we now well, then move them from new york to philadelphia or fly them to london to play in another venue, that same symphony, same conductor will sound different, will they not?

d. i think i have read more than my share on music production, and the guy that sits behind the console, tailoring the sound to suit both himself, the band, the label (and maybe the janitor) and in the end it is rare that the result sounds anything like what was originally played behind the glass... every singer wants to sound much bigger and better than he or she really is, and that probably goes for the individual band members as well. so what is true? and what is untrue? and what about the monitors that the engineer is using? should we all be using the same monitor that he was using and forget doing anything else? arguably and decidedly not!

e. i know we talked a bit about room and its dynamic affect on what the speakers try to do, how they are set up makes a huge difference in how things sound, or how true to whatever standard we are trying to chase (er adhere to). out of 100 homes maybe 2 or 3 are enough alike to be something that works with measurements.

f. ( a bit of a sidebar) back in the 60's and early 70's when solid state was all the rage, and every manufacture was touting 0.00001% total harmonic distortion (only a slight exaggeration), and we all new that something still sounded bad! and we all tried different speakers, hanging towels over them, etc, trying to make them sound better... all the while a typical tube amp SE triode my have 5% 2nd harmonic distortion, (oh my god, we can't have that crap) funny thing was the tube amp sounded better, even with crappy speakers.

so i am still hung up with this...

bearing all this in mind, again what would i measure, and to what end? what is the end goal everyone is trying to achieve?

using me as an example: if the speakers sound good to me, i can sit and enjoy them for hours, and have a smile on my face, then i guess i can measure smiles per hour? or i can get onto the neurotic treadmill of measurement, only to find "oh my lord, there is a huge hump at 1300hz or whereever, then what? i spend hours and hours trying to get rid of that hump, and maybe if i am lucky (or with math, measurement and money) i fix the hump and i have a nice flat speaker response, only to sit back down and find that the music i know best and listen to most now sounds wrong, or.... bad? then what have i accomplished? i have spent alot of time, measuring, doing math, spending money, and enjoy the music less? something seems fundamentally wrong with that.

now on the other hand, if the goal is one of "mental exercise" where one is setting out to learn every detail of speaker design, testing, measuring, researching, (wash, rinse repeat ad nauseum) then i can get my head around that. been there done that with the best of them on other unrelated stuff as previously mentioned. i understand this way of thinking and i appreciate it for what it is worth..

that being the value is in the journey, not the destination.

i guess so far i am happy with the destination, and am ok with understanding that there are some things i don't really need to know.

at least not yet

the next speaker project may well change my thinking on this matter and i will do a 180 and get in line to do all the measurement, math, research, study, spending etc.

one last parting thought

if one were to go out and buy a speaker pair from a seller, well regarded, well reviewed, and bought it home, set it up correctly, had good source material and good equipment, and really enjoyed the outcome. what would he do if someone else came in and wanted to measure his speakers and then found out "hey Joe, these things have 3 big peaks and a couple grand canyon dips".... should he now enjoy his speakers less? should he take them back and get his money back and buy something else?

ok guys school me, i am all ears (er eyes, at least one eye, they postponed cataract surgery because of the virus).

(i digress, something i am well known for)

thanks guys

bob g

 

[lovinthehd]

if one were to go out and buy a speaker pair from a seller, well regarded, well reviewed, and bought it home, set it up correctly, had good source material and good equipment, and really enjoyed the outcome. what would he do if someone else came in and wanted to measure his speakers and then found out "hey Joe, these things have 3 big peaks and a couple grand canyon dips".... should he now enjoy his speakers less? should he take them back and get his money back and buy something else?

I'll just start with the last bit with a nit pick . You wouldn't measure the speakers particularly but the response at given points in the room (depending on your needs). Measuring speakers you're making is a bit different. If the guy wanted to experiment or not would be a personal choice, just like you choosing to put together speakers from odds and ends for fun. Personally I'd be curious if it could be improved upon by improving response, whether it was simply a matter of finding a better spot for the speakers or the seat, or (horrors) applying a bit of eq. Or not. Some guys buy ridiculously expensive cables to try and tweak the sound without trying science YMMV.

As to measuring gear for speaker making, a DATS kit from Parts-Express could help identify T/S parameters if you didn't have those among other things for speaker design/measurement. They bundle it with their Omnimic kit (measuring mic, software package) for room measurement....but for room measurement you could buy a measurement mic and use REW software for less $.