The silk purse project: a musical studio monitor ...

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This is a continuation of an exercise, the progress of which was commented on, on another forum up to this point, but now that forum is unavailable to me. So to keep the ball rolling, and maintain the energy, I'll keep company with you good folks! ;)

The idea is simple, and done by many people to some degree: a decent active studio monitor, cheap to buy, but handicapped by cost cutting to get the product out there, and a lack of understanding of the subtle factors that cripple the potential sound quality, will be upgraded, tweaked to get the full, generous audio sound that the drivers and internal amps are intrinsically capable of delivering.

I've been doing this type of re-engineering for over 25 years, and have learnt a lot along the way, the most important thing being that bargain basement equipment is capable of producing rich, realistic, convincing sound if the right steps are taken ...

'Nuff for now ...

Cheers,
Frank
 
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Okay, a bit more on what this is all about: the title of the thread is just a bit of a poke at what some people may think of studio monitors - all well and good as a tool for "monitoring", hah, progress on a recording project, but not the first choice for pleasurable listening to an album collection. Well, I'm one of those strange people who have unusual, and controversial, ideas on what can be achieved in audio reproduction, the core of which is that a much higher standard of sound quality can be achieved then is normally realised; even with what is considered very modest equipment.

That's the silk purse part, what's with the "musical" tag? Well, many debates and slanging matches can be found on audio forums on how if a system is highly "revealing", which is what studio monitors are supposed to be all about, then they haven't much chance of sounding "nice", being enjoyable to listen to, as a mechanism for reproducing music.

So, an extra part of my "weirdness" is that I believe you can get both truth (there's a clue ... :)) and tonality in one package, which means, amazingly enough ;), that it sounds like the "real thing", you can be fooled into thinking that you're listening to the real deal very easily.

I've achieved various versions of that over the years, so now the task is to do the same with a standard active monitor, one of the better low cost items on the market. Like all reasonable monitors it can go to the red line, overload levels, without falling to pieces but it doesn't sound "big" doing it, because of various limitations. This "size of sound" normally mean this size of monitor is called, and used as, a near field device, it serves as a set of oversized headphones. But this restriction is not fixed, the limitations can be overcome, and the sound can become room filling, and all the other myriad adjectives used to describe "good" sound.

Frank
 
Hi,

A load of fanciful claims and no substance doesn't add up to anything.

rgds, sreten.
The "substance" is what I've achieved to date, fooling around with other gear. So I know what can be done, in simple terms, achieving decent, not stupid, PA levels of intensity of sound, while still retaining, projecting the quality aspect.

The key part of the battle is attention to detail, where the devil is, of course. Trite, yes, but unfortunately true -- unless every, and I repeat, every issue is addressed then you won't achieve the "right" result, it will fall well short.

Frank
 
Well, at the moment it looks like it's a non-starter, after that cheery round of greetings ...

You want a photo? Wander down to your nearest pro music shop, take a snap of a near field monitor, any one of them and plonk it down in front of you -- 'cause that's exactly what it looks like to me at the moment.

Geez, "concept" seems to be such a difficult concept for people to handle ...

I agree, this is just going to be a big waste of time, pearls and all that sort of thing, I'm outta here ...

Cheers,
Frank
 
You are suggesting that a random self powered inexpensive "monitor" from a typical consumer music store can be upgraded via modifications of the *drivers*??

Are you also suggesting that it doesn't matter which brand, which drivers, and all of the other parameters and facets exist?

It's a nice "concept" but rather nearly impossible in reality.

I would agree that one could improve upon things like xover components, and maybe re-engineer the xovers, but modifying the drivers themselves is not terribly practical, save something like an Enable type treatment or maybe a C34 coating??

Perhaps if you had laid out what sort of things you have had success doing for 25 years now, there would be something more to talk about. Unfortunately speaking at least for myself I can't read ur mind.

Have you looked around this site? Looked at some of the speaker designs and discussions? A lot of them are pretty close to leading edge in terms of theory and design. Including measurements. Not everyone here is a newbie...

I think almost all of us are open to new ideas and even old ideas done well...

If you have something to say, just go ahead and say it... the discussion will ensue shortly thereafter. Buckle your seatbelt.

Welcome to DiyAudio. :D

_-_-bear
 
"Improving" a cheap-n-cheerful speaker is pretty simple. The drivers these days are very inexpensive Chinese drivers that superficially resemble expensive European drivers. The tweeter is typically the cheapest and worst-sounding driver, so it's an obvious candidate for replacement. Of course, that usually means hacking the faceplate to accomodate a driver with different mounting holes and overall dimensions.

Assuming the original speaker has a competently designed crossover, if the tweeter is replaced, then the crossover has to be adjusted as well. With instrumentation and a test microphone, not just tweaking around randomly with a box full of parts.

If the crossover is active, then the circuit board for the active crossover has to be removed from the cabinet, the schematic figured out, traces moved, new parts added, and replaced in the cabinet. While it's out on the test bench, might as well upgrade the low-quality 25-cent opamps with modern, good-quality opamps while you're at it. Re-measure and re-listen. Repeat until satisfied with the result. Write article or publish on the Web.

To go further, the woofer can be replaced as well, the cabinet modified for the different mounting holes and woofer diameter, and the crossover re-configured again to match the new driver. Keep or discard the original built-in power amplifier? Good question. Depends how it measures and sounds.

All that's left of the original speaker is the cabinet. Is that worth keeping? If it isn't, all that's now left of the original speaker are a few lengths of wire and speaker terminals.
 
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I was assuming we were going to take something like a Behringer 2031A (2 way, 8", active, affordable) and see what tweaks are on the table.

Whenever I see a measured FR of a Behringer it looks nice and smooth and flat, off axis too, so it seems a decent start.

Although Lynno's post is true enough, I thought we would be keeping the drivers and looking at any gains from astute use of felt or resin (on or around the cone/dome), replacement of dust cap, stiffening or dampening the pressed steel driver frame... what else?

The cabinet. Anything to gain from spikes? How about those 2 slots it uses instead of a round port.... is it an improvement on a traditional port or better blocked and a trad port put on the back? How about building a stiffening matrix into the cabinet without taking away critical volume? Or even glue/screw heavy duty plates on the outside of the cabinet? Is it an idea to put large radius closed cell foam or cardboard curves on the sides top and bottom of the cabinet to prevent reflections of radial energy?

I don't know what we would see when we open up the electronics, probably a single small PSU, two IC power amp modules and definitely a LR4 line level crossover. Maybe the PSU is a bit light on caps? How about adding a separate PSU for the tweeter? And another for the line level crossover? Is there a critical cap or two that could be changed to PP? Are any IC's upgradable and will it help? How about moving all the electronics out of the cabinet and away from that energy intensity?

But then the OP let it peter out, but I am quite interested so thought I would toss some ideas in the fire. Am I on a sane path here?
 
Hi,

The point is the OP claims to know stuff that "cripples" typical active monitors.
I don't think so, and I'm not being shy about it. I don't care what you can
do to a cheap Chinese knock off, that is not the gist of the original post.

The original post claims improvements "to get the best out of the fitted
drivers and amplifiers", and this uncrippling process might be interesting
if any details where given, but I severely suspect will not be forthcoming.

rgds, sreten.
 
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Well, at the moment it looks like it's a non-starter, after that cheery round of greetings ...

You want a photo? Wander down to your nearest pro music shop, take a snap of a near field monitor, any one of them and plonk it down in front of you -- 'cause that's exactly what it looks like to me at the moment.

Geez, "concept" seems to be such a difficult concept for people to handle ...

I agree, this is just going to be a big waste of time, pearls and all that sort of thing, I'm outta here ...

Cheers,
Frank

Gosh don't run off when it was just beginning to get........well not good.........not much of anything really. If you get discouraged so easily then you need a thicker skin online.:confused:
 
A quick placeholder to note that I haven't gone away - I had a small chat with bear, and will aim to rejig how to relate what I'm doing, and how I go about things. The last couple of days have been hectic, so haven't had a chance to get on top of doing a solid follow up, plus I want to get a better idea of how people here relate to particular situations. To get the drift of where I'm coming from, the thread discussing John Curl's Blowtorch IP "dilemma" is right on the money, this is an angle I'm concerned about.

The other factor is, that what I'm about is system engineering, not component optimisation: as far as I'm concerned the music making machine is a circuit which includes the mains supply electrical behaviour, and antennae picking up RF interference. So this may not be the right forum for what I focus on ...


More coming soon ...

Frank
 
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