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Discussion Starter #1
I need some good monitors with accurate bass

my old Fostex PM .4's have been useful for years, but they don't have any bass. I'll keep them around as reference but I now know they are not reliable

what is everyone here using?

ps I plan to do some room treatment as well, but may be moving soon so nothing too radical

thx!!
 

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Those fostexes are a case study in why you shouldn't use bass reflex cabs (ported) with small woofers. Sorry, I have strong opinions on that. The usual solution (putting them up against a wall) may not even help that much.

Anyway, since personally I am of the opinion that at best crossovers are a necessary evil to be avoided whenever possible and multi-way speakers are evil (in near feild listening situations, such as when mixing), I recommend anything single driver or coaxial. There are now a few cheaper options in this category (used to be high end stuff only), such as the Presonous Sceptre line, Equator D series, and the Fluid Audio FX8 (none of which I have tried; I have heard the Equator, but not enough to say I am familiar). The FX8 in particular is pretty affordable. Personally I am a huge fan of vintage Tannoys (that's how you do bass reflex - with a 15") but they ain't cheap.

Since I can't afford anything that good (and because everything, or almost, is bass reflex these days and I hate bass reflex, barring the noted exception case - large woofers) I built my own monitors, so not much help but let me explain some of the whys and wherefores of my opinions above, because they could inform your short list process.

Bass reflex - makes for smaller cabs at the cost of low end extension (assuming same drive unit). The response will remain flatter until lower, but then fall sharply off a cliff just below the port tuning. In comparison, regular acoustic suspension (sealed) starts to roll off earlier, but much slower, so it actually has more useful bass extension than the same driver in a ported cab. This slower rolloff is also more natural sounding. This is why I say you should only port a cab with a large speaker (e.g. where there won't be much musical information below the port tuning anyway). My issues with bass reflex and small woofers are further exacerbated by a little trick some manufacturers of (especially but not exclusively) lower end small speakers use: I call it bump before dump - the port tuning is designed so as to create a mild peak in bass response before the response falls off the aforementioned cliff. This is basically the same as what some revered studio EQs do (see 'resonant filter' - which can be great, but not in your monitors). This gives the psycho-acoustic illusion of more bass without there actually being any. Makes it sound tighter, but deceptively - you won't know if you have a low end buildup problem if it's below the port tuning (which can be as high as 80-100-some odd hz with smaller speakers). Bass reflex is hard to avoid these days so try to go for a speaker that has at least an 8" driver (technology has advanced considerably since the vintage Tannoy days - a modern 8" driver can often be tuned pretty low).

Crossovers - always create phase problems in the overlap region (where both the woof and tweet are both making the same sound). The problem is where this region is - upper mids usually, which is the critical area for intelligibility - clarity of tone and words critical to vocals and guitar. To combat this they came up with 3 ways (see vintage JBL monitorss from the 70s), but then you have 2 muddy regions (but at least not in the main critical area). They are a necessary evil however, since the only way around it is to use a single fullrange driver (there's trade offs - but that is my preference). It can be mitigated by using an extended range woofer with a supertweeter - moves the crossover point up, out of the critical range (this is my second choice and most coaxials fall into this category). Some designs try moving the crossover down - I would avoid these - makes for a tight sweet spot (tweeters have poor off axis response and would be doing more work this way). There's also the danger of getting into the mud region and making it worse. IMHO supertweeters are the way to go in this application (if full range isn't your thing).

Multiway - the other problem with multiway speakers (after the crossover) is that (in the crossover range) the same sound comes from 2 points at least 3 inches apart. if not more. In a living room or especially a club situation (where you are meters away from the speakers) this is of little concequance, but in near field monitorring you are a meter, maybe 2 away and this causes a significant time differential between the sound from the tweet and the woof getting to your ears. The effect is phasing, or a general muddiness or lack of clarity. I did not even notice how unclear things where until I tried single driver speakers. It also compounds the phase issues caused by the crossover itself (which is electrical in nature vs acoustic).

Modern (at least higher end) active monitors have DSP signal processing (usually involves delay) to compensate for the problems caused by crossovers and multi-way configurations, but it's still, IMHO , they are not perfectly eliminated (maybe the very high end stuff, which I don't get to listen to much) and my position when presented with a problem is to KISS it - sometimes low tech is better.

Another key feature to look for in a monitor is room mode switch (sometimes called other things, such as 'acoustic space' etc). What this is is a bass response compensation circuit for use when the speakers are up against a wall vs out in the room and sometimes even vs in a corner (see the Mackie HR8 mki as an example of the 3 option switch). Otherwise you get a speaker designed to be flat in an anechoic chamber, and then (because it's usually most convenient) you put them up against a wall and too much bass. I recommend reading up about this topic as well as placement generally.

Anyway, here's my DIY monitors. The white ones are at my studio, the natural ones were the prototypes (and gift for my wife who wanted smaller speakers for the living room stereo (we had 15" Technics), and the Red ones are my younger brother's. They use a 4" full range drive unit in a transmission line enclosure (which can extend bass response by an octave or 2 below the driver's resonant frequency. Designed to be mounted directly on a wall, (integrated hardware and cable management for that purpose). The baffle is mechanically decoupled (glued to the box with a conpressive constrained layer in between - no fasteners) so that transfer of vibrations from the driver's motor structure to the cabinet are minimised.






The benefit is clarity and detail and soundtstaging that is unmatched by commercial offerings I have used (so nothing too esoteric or expensive; , but I'd wager that they would be very competitive) . The trade off is a little bit of extension at the extremes; mostly the top end above 15k or so (a supertweeter could fix that, or switching to a coaxial driver - considerred the supertweeter route but decided I didn't need them). The bass is ample (not exaggerated) when mounted on a wall; a little lean if a foot or more away from a wall.
 
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Discussion Starter #3
hot damn....thanks for the detailed response!!

reading
 
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