4.5" vs 6.5" Trade offs

[musgofasa]

I don't have as much experience as many of the other posters here, but I will offer my "observations".

The smaller drivers (specifically the 4.5" fostex I have heard) seem to handle the very high frequencies with a finesse that I like. Many tweeters and supertweeters and even the ribbons I have heard just don't seem to have the airy sound and ambient energy that these FR drivers possess. By Themselves, they don't have ground shaking bass output so a sub might be in order if you like that kind of thing. The ability to work in the vocal range and the high cymbals etc is just lovely with the smaller drivers. I imagine from reading that the treated drivers are that much better. I have only heard one pair of modified 126 drivers (not Dave's) and they were just about the sweetest sounding thing ever.

I liked the combination of this driver with another unit that put out a bit more dynamic output. Two FRs in this case, but the Fostex was obviously handling the mid to high end and the other driver was going mid to low end just by their character. Bear in mind there was no x-over involved so you have to keep that in mind.

The larger drivers often need a little help at both ends. A supertweeter might help get closer to the smaller driver's abilities in the high end, but the larger drivers (6.5") still won't put out 30hz at 100db very easily. If you like that bottom end, you will still need a sub so now instead of 1 helper, you are looking at two and more x-over.

If you don't need the house rattling bass, a lot can be gotten from the smaller driver in the right cabinet. A WHOLE LOT.

Just my thoughts on it.

Take care,
Robert

[planet10]

Originally posted by Zero One
Larger drivers have more dynamic impact I guess but in general I would trade this for clarity and mid range finess at any time.

And woofers with simple active hi-pass* can give back much of those dynamics and produce bass most full-ranges would never hope to.

* (ie PLLXO or better yet, a suitably choosen coupling cap)

dave

[chrisb]

Originally posted by musgofasa
I don't have as much experience as many of the other posters here, but I will offer my "observations".

The smaller drivers (specifically the 4.5" fostex I have heard) seem to handle the very high frequencies with a finesse that I like. Many tweeters and supertweeters and even the ribbons I have heard just don't seem to have the airy sound and ambient energy that these FR drivers possess. By Themselves, they don't have ground shaking bass output so a sub might be in order if you like that kind of thing. The ability to work in the vocal range and the high cymbals etc is just lovely with the smaller drivers. I imagine from reading that the treated drivers are that much better. I have only heard one pair of modified 126 drivers (not Dave's) and they were just about the sweetest sounding thing ever.

I liked the combination of this driver with another unit that put out a bit more dynamic output. Two FRs in this case, but the Fostex was obviously handling the mid to high end and the other driver was going mid to low end just by their character. Bear in mind there was no x-over involved so you have to keep that in mind.

The larger drivers often need a little help at both ends. A supertweeter might help get closer to the smaller driver's abilities in the high end, but the larger drivers (6.5") still won't put out 30hz at 100db very easily. If you like that bottom end, you will still need a sub so now instead of 1 helper, you are looking at two and more x-over.

If you don't need the house rattling bass, a lot can be gotten from the smaller driver in the right cabinet. A WHOLE LOT.

Just my thoughts on it.

Take care,
Robert

If your project plans definitely include stereo bass drivers, then another quite special driver (although it certainly has X-max limitations) is the Fostex FF85K - particularly when utilized in a OB configuration.

XO around 150Hz or so in sealed or resistively ported enclosure, or an octave or so higher in OB, this little guy can give some high-end tweeters a run for the money.

[kvk]

Hopefully my last follow-up question on this thread.

What's the preferred amp to drive these 4.5" speakers?

I'm just reading specs now but they don't look quite efficient enough for lower powered SETs? If they aren't supposed to sound good with SS, would you use PP tubes? Or maybe a tube pre with an SS amp?

[DaveCan]

Hi kvk,
I listen to lots of folkish and jazz music also. The smaller drivers definitely do have the midrange magic over the larger drivers.. Anyhow I use the fe108es drivers which are 90db with a Decware Taboo 6w SEP amp, and it will get about medium loud in volume.. The 126 driver will go somewhat louder still, and the larger Fostex will get very loud with that same 6w...

As to the preferred amp Id say Tubes are where its at Depending on how much money you want to spend there are some regarded tube amps in the higher watt class,the Decware Torii or the Jim McShane redone Citation amps, plus the McAlister amps are even more wattage for the money spent..

I would very much recommend that if really loud volumes are desired for most listening, or for parties and such then you want the larger 8'' drivers. You'll still get very good sound that will impress your ears in the right cab... Also I've never heard the larger 6-8'' AER or Lowther drivers, but I would imagine that they would have the same or better midrange magic as the smaller Fostex drivers.. Dave

[cabbagerat]

Originally posted by kvk

What's the preferred amp to drive these 4.5" speakers?

I'm just reading specs now but they don't look quite efficient enough for lower powered SETs? If they aren't supposed to sound good with SS, would you use PP tubes? Or maybe a tube pre with an SS amp?

Depends if you are looking to DIY the amp or not. I have mine driven with an LM3886 based chip amp, which I think is great. I listen mostly to 60s and 70s rock, jazz, classical and some modern rock and metal. Not having passive crossovers makes full rangers a very easy load to drive, and most amps will do just fine (40W or so should be plenty). Before the chipamp, I had a very unremarkable MOSFET based amp, which is now powering the subwoofer in that system.

A good tube preamp could be a great addition

[kvk]

Originally posted by DaveCan
...redone Citation amps

Please don't make me cry. My Dad put together a full HK Citation line, tuner, preamp, amp in about 1960 plus or minus a few years. About 20 years ago, he was confvinced old tube stuff was junk but I couldn't convince him otherwise. He tossed it all for a cheap RatShack receiver.

I had told him to give it to me if he ever wanted to get rid of it but he forgot. If he had given it to me, I would have spared no expense restoring it to cherry :-( :-( :-(

[JandG]

If I was you ...I would go small 4-5" . 108 etc...& find a desighn & driver combo that runs no filter's. If the driver is behaved enough this is the ultimate for it's scale in the heart of the music. i run multiple OB systems, with everything from 45 to PIM, 300B PP into hybrid OB using SEAS 5". & so on. Filters sure enough do there job,...but ..Filterless FR is something to be in ah of when it comes together. any amp is fine..but I am severly tube biased for reason I think they just do the job of music repro better than anything. Especially DHT SET. SET into 108...oh boy PP 6550 in triode or 2a3 PP would be the swell also. Heck I even like a 45 into small drivers for low volume stuff. mmmm 45 & filterless FR..My ultimate. Yep, please try the little critters if you don't need big scale, then you can later build a hybrid OB or something similar based on this little FR driver & have all kinds of fun.
J & G

[Jeb-D.]

Please don't make me cry. My Dad put together a full HK Citation line, tuner, preamp, amp in about 1960 plus or minus a few years. About 20 years ago, he was confvinced old tube stuff was junk but I couldn't convince him otherwise. He tossed it all for a cheap RatShack receiver.

That sucks! He didn't notice the degraded sound quality when he started using the receiver?

[ped]

Originally posted by kvk
Hopefully my last follow-up question on this thread.

What's the preferred amp to drive these 4.5" speakers?

I'm just reading specs now but they don't look quite efficient enough for lower powered SETs? If they aren't supposed to sound good with SS, would you use PP tubes? Or maybe a tube pre with an SS amp?

I'm using an Emotiva LPA-1 SS amp to drive the FE-127eN in Fonken cabinets with ~3db of BSC and actively xo'd to a sub @60hz and I am extremely happy with the setup. There are also many "T-amps" that reportedly work with well with the various Fostex drivers. I have an Amp6 Basic which sounds good, but I still prefer the Emo amp.