[FreedomJazzDance]

Hello to all,

Would like to learn more about multi amplification and active crossover, thinking about to consider this Accuphase combo for tri-amp the loudspeakers that I'm planning to build, and use an active crossover, instead of to build the passive one recommended by the manufacturer.

Please take a look, appreciate very much the thoughts from more experienced people about this particular solution

Loudspeakers: 3 way: 12" woofer + Radial Horn + Super Horn Tweeter:

https://www.fostexinternational.com/docs/speaker_components/pdf/recom_enclose/w300aII_encl.pdf

Multi amp and active crossover combo:

http://www.accuphase.com/cat/px-600e.pdf
http://www.accuphase.com/historys/pdf/cx-260e.pdf
http://www.accuphase.com/cat/f-25en.pdf

Do you think they will be a good match for this particular speakers? Let me know your thoughts...

Thanks to all, best regards.

[JLM]

Active is the best way to go IMO.  They have many technical and performance advantages and thus are preferred by recording professionals.  18 years ago compared Paradigm Studio 20 v.2 ($800/pair, 2-way monitors) vs. Paradigm Active 20 ($1600/pair, same drivers/cabinet) in an average sized room and it was no contest.  The Actives were way more dynamic, offered flatter frequency response, better imaging, and had tremendously deeper/fuller bass (comparable to floor standing Paradigm Studio 80 v.2).  It was an epiphany and never looked back.

Most active speakers are 2-way because of weight, size, cost, complexity, and performance considerations.  By performance I mean that for most situations 3-way performance isn't needed (most are used in smaller recording/mixing control rooms.  Recommend reading Floyd Toole's "Sound Reproduction" 3rd edition to learn how bass behaves in-room.  The best positions to generate mids/treble are completely different from bass.  Mids/treble generation (except for odd ball designs) should be located away from walls and side-by-side to reduce room effects and improve imaging.  Bass generation should be near corners and be composed of 3 or 4 sources to minimize peaks/dips.  So the ideal solution would involve 3 - 4 subs carefully located near corners and a pair of symmetrically located smaller active monitors.

Typically active speakers are not DIY due to the effort needed to properly design the overall product and the cost to produce a presentable speaker.  Hobbyists types that just pull together favorite amps and drivers fail to get an optimal design.  Major R&D efforts from leading companies like JBL, Dynaudio, and Klein & Hummel is needed to create solid offerings.  Your driver idea (number and sizes) is overblown.  I have a pair of JBL 708Ps, 2-way active monitors with wave guide loaded 1 inch compression driver and 8 inch ported woofer that are extremely dynamic, detailed, and imaging champs.  My room is roughly 3/4's the size of yours and they fill my entire basement (160 m2).  Just the design of a defraction limiting cabinet goes well beyond what most manufacturers, let alone hobbyists can come up with.

[gab]

Whatever you do, go with a well engineered & proven design. My preference is the LX521.4

gab

[FreedomJazzDance]

Thanks for the contribution, purchased the first speaker's drivers this days

Trying to find people that had contact with the Accuphase amplification and active crossover mentioned earlier, found tons of marvelous experiences about the F-25 and other previous generations  Accuphase active crossover, but not too much info about the amp mentioned.

If you guys know someone, appreciate if can put me in contact, many thanks, best regards..

[ricmon]

Typically active speakers are not DIY due to the effort needed to properly design the overall product and the cost to produce a presentable speaker.  Hobbyists types that just pull together favorite amps and drivers fail to get an optimal design.  Major R&D efforts from leading companies like JBL, Dynaudio, and Klein & Hummel is needed to create solid offerings.  Your driver idea (number and sizes) is overblown.  I have a pair of JBL 708Ps, 2-way active monitors with wave guide loaded 1 inch compression driver and 8 inch ported woofer that are extremely dynamic, detailed, and imaging champs.  My room is roughly 3/4's the size of yours and they fill my entire basement (160 m2).  Just the design of a defraction limiting cabinet goes well beyond what most manufacturers, let alone hobbyists can come up with.

Definitely not true.  DIY active speaker are super easy.  Given all the amazing digital crossover solution such as DEQX.  With a little home work and some commitment to learning the basic of speaker building.  Putting in the time to learn the software do your measurements and experiment until you get good sounding results.

Have fune.
Ric

[JLM]

Definitely not true.  DIY active speaker are super easy.  Given all the amazing digital crossover solution such as DEQX.  With a little home work and some commitment to learning the basic of speaker building.  Putting in the time to learn the software do your measurements and experiment until you get good sounding results.

Have fune.
Ric

The key word is "properly".  Almost anyone can throw together drivers and amps, and come up with crossovers.  Equating "super easy" DIY efforts with decades of R&D experience, vast resources of in-house manufacturing know how, and state of the art testing facilities of companies like Genelec, Focal, and Adam (just to name a few more examples) is the epitome of proud papa foolishness.  Even Bryston's active offerings are quite amateurish in comparison, where they simply plug their amps into existing speakers and add a hard wired crossover.

[gab]

deleted

[woodsyi]

Thanks for the contribution, purchased the first speaker's drivers this days

Trying to find people that had contact with the Accuphase amplification and active crossover mentioned earlier, found tons of marvelous experiences about the F-25 and other previous generations  Accuphase active crossover, but not too much info about the amp mentioned.

If you guys know someone, appreciate if can put me in contact, many thanks, best regards..

I admire your resolve on your decision and godspeed.

This explains somewhat of the crossover aspect http://www.rane.com/note160.html.
The box you build may be different than the model requiring different values.
Accuphase does not have 1st order.
Do they have modules for your needs, once you figure them out?

Really,  good luck.  It will be awesome when you get it right.

[FreedomJazzDance]

Hello!

I must say that I have a lot to learn about which crossover specs will work with the drivers of the loudspeakers, I just started to think about the idea, the general concept, and etc..

for what I saw in general about the Accuphase crossovers, appears that they are very complete, and the F-25 modular model is the biggest one, I presume the F-25 is the one with the biggest room for frequency division, BUT, technically: I must say that I don't know how to check exactly which will be better and work optimally with the drivers in question

Still have a lot to learn, and as this project will be quite long, purchased just the first loudspeaker components, I have plenty of time to learn, and will start with the article that you shared

Thanks sir.

[FreedomJazzDance]

Hello!

I must say that I have a lot to learn about which crossover specs will work with the drivers of the loudspeakers, I just started to think about the idea, the general concept, and etc..

for what I saw in general about the Accuphase crossovers, appears that they are very complete, and the F-25 modular model is the biggest one, I presume the F-25 is the one with the biggest room for frequency division, BUT, technically: I must say that I don't know how to check exactly which will be better and work optimally with the drivers in question

Still have a lot to learn, and as this project will be quite long, purchased just the first loudspeaker components, I have plenty of time to learn, and will start with the article that you shared

Thanks sir.

[FreedomJazzDance]

But as I said, I need to learn more about the technical aspects, for now, the general idea seams very interest, but I need to learn how to interpret the speakers driver's specs, and the crossover specs, to know with certainty if it's a good match, will try reading about the F15L specs, that appears to be more straight forward to learn...

http://www.accuphase.com/cat/f-15len.pdf
 
If you can take a look, and notice something important about that match, I really appreciate advices..
 
Thanks sir.

[ricmon]

The key word is "properly".  Almost anyone can throw together drivers and amps, and come up with crossovers.  Equating "super easy" DIY efforts with decades of R&D experience, vast resources of in-house manufacturing know how, and state of the art testing facilities of companies like Genelec, Focal, and Adam (just to name a few more examples) is the epitome of proud papa foolishness.  Even Bryston's active offerings are quite amateurish in comparison, where they simply plug their amps into existing speakers and add a hard wired crossover.

I get all of that but.......if you start with an excellent kit were the drivers have been properly sourced and matched and the cabinets designed properly (like from Madisound, PartsExpress or our own GR Research) you can get super excellent results.   Just go on the speaker building threads here on Audio Circle.  BTW I spent some tine with one of our superb diy speaker builders from the DC DIY audio group......if you heard those you would quickly change your opinion.  This particular gentleman also judges the diy speaker competition for Parts Express and his speakers where jaw dropping!

Ric

[FullRangeMan]

IMO active diy 3-way system  requires a lot of research, a lot of practical testing, previous experience, its not a purist system like an FR driver, its actually the opposite of that, and once done it's hard to sell as used because no one wants it, too complex.

[audioengr]

To do a bi or tri-amped system properly, you will need a calibrated microphone, a preamp for it and a good spectrum analyzer.  Only them will you be able to properly cross-over the drivers and adjust the amplitudes to match them. IF you don't know how to do this, I would avoid this kind of system.  It's very difficult for even pros to get a good match.

You are better off to get a speaker with a good minimum-order crossover design and use a single amp for each speaker.

Your money would be better spent IMO on a pair of good SET tube monoblocks and a good tube preamp.

Steve N.

[FreedomJazzDance]

Interesting, well... I think maybe worth more just build the passive crossover that is provided on the Fostex plan, so, after that get a active crossover, maybe the Accuphase F15L, and start to experiment

[JLM]

I get all of that but.......if you start with an excellent kit were the drivers have been properly sourced and matched and the cabinets designed properly (like from Madisound, PartsExpress or our own GR Research) you can get super excellent results.   Just go on the speaker building threads here on Audio Circle.  BTW I spent some tine with one of our superb diy speaker builders from the DC DIY audio group......if you heard those you would quickly change your opinion.  This particular gentleman also judges the diy speaker competition for Parts Express and his speakers where jaw dropping!

Ric

Agree that active design has many advantages over passive.  Have been pushing that agenda for years here at Audio Circle.  The performance and value of something like JBL 305 Mk2 ($300 MSRP/pair, 2-way active small monitor) is simply amazing. 

Again watch out for DIY proud papa syndrome.  An assemble of amps and some sort of crossover is not an elegant solution or particularly inexpensive versus manufactured product you can listen to first.  How many attempts, hours, and wasted parts will it take to "get it right"?  How many years of experience did this "particular gentleman" have to invest to develop his speakers?  If that's your thing, great.

[JohnR]

Um, this is "The Lab" - it's specifically here for people who are interested in DIY.

[FreedomJazzDance]

Thinking about here, the tri-amp solution with the multichannel amp, what do you guys think of multichannel amp solution in particular?

Still will deliver a lot of the advantages of a active tri-amp system?

I know that the optimum way is with separated amps for each driver, but due the high costs of acquire 3 amps, what about a nice multi channel?

Appears that most are designed for home theaters or pro audio... what about HiFi Stereo, focused on bi-amp, tri-amp and etc?

I mentioned the Accuphase PX-600, because appears to be the logical option, when considering the crossovers already mentioned, (the F-15L appears for reasonable prices frequently, lot's of amazing reviews from users)  meanwhile the PX-600  don’t appear very often, but according to my researches, they appear from time to time in Japan, found some in online auctions that was sold for prices not so extravagant... still costly, but, considering the price of acquire separated amps for the same performance level, still worth it..

Anyway, that’s it, appreciate very much all the thoughts about the multichannel amp solution... 

Many thanks, best regards.

Appreciate very much suggestions, vintage or actual in production...

[FreedomJazzDance]

Um, this is "The Lab" - it's specifically here for people who are interested in DIY.

Oh sorry, do you think it's better move this thread for another section?

Please let me know, I have to say that when was creating this thread, i was in doubt, where exactly to create, here, speakers section, or amplifiers...

Sorry if is not according to the "The Lab" theme...

[JohnR]

Older Rotel multichannel amps can be a cheap way to get a bunch of channels, the RB-976 and RMB-1066 in particular. They can be getting a bit long in the tooth now but they seem quite reliable.

IMO cheap is good when you're at the start of the learning curve.

The other point that was mentioned (in a negative way, oddly) was speaker measurement - this is something you will need to learn or you will hit a wall. It's not expensive to do these days.