[JLM]

Recently picked these active reference studio monitors up very slightly used.  Reference studio monitors are used at the very best studios to produce the music, often audiophile quality recordings, we listen to.  Active refers to the design where the low voltage signal passes through the crossover before the power amps (one channel of amplification per driver).  Self-contained 2 and 3 way active monitors are common for studio work and have started to make an impact in the audiophile world. 

Active design can have several advantages.  Dynamics greatly enhanced, frequency response remarkably flat, and bass amazingly deep/full.  Phase between drivers and other parameters can be corrected via use of a sophisticated crossover.  The amps ‘see’ a simpler, more direct load to optimally synergize with the driver by the designer who is the position to select the amps.  Note that most studio monitors are 2-way designs.

Studio monitors are intended for serious work, to find any flaws and come up with a sound that ‘translates’ correctly to the majority of consumer speakers and headphones.  Unlike consumer speakers they’re primary purpose is not produce a pleasing, entertaining sound but an accurate sound to expedite the work at hand.  Using reference studio monitors at home means you are entering the prosumer realm and want to hear the truth.

By the way James Bullough Lansing was a pioneering American audio engineer and started both Altec (All Technical Services Corporation) Lansing (1927) and JBL (1946).  Now under the Harmon International umbrella with Crown, JBL has vast resources to develop all aspects of a studio monitor that few companies can match and is about as far away from DIY or mom and pop shops as you can imagine.

If you’ve followed jtwrace’s “My Harmon (JBL M2) Trip” thread in the Enclosures Circle, you’ll have an idea of the background of this family of studio monitors (305, 306, 308, 705i, 705P, 708i, 708P, and M2) which were first introduced a couple of years ago and covers a wide range of sizes and price ranges (from a small monitor at $150 MSRP each up to floor standers at $10,000 each MSRP).  The third digit in the 3XX and 7XX models represent woofer diameter (in inches).   

The 3 series are the high value options while the M2 is the statement product.  In between is the 7 series that are truly reference studio monitors.  None of these will win a beauty contest, they all come in black matte or satin, which is a plus in my book as these are machines, not furniture and no money is wasted in fancy veneering or finishes.  708P currently retails for $2000 each, was introduced last spring.

The entire series are 2-way speakers uses waveguide loaded tweeters to achieve constant directivity (search Earl Geddes or Audio Circle’s own Duke LeJeune - Audio Kinesis for more information) and ported cabinets.  The 305, 306, 308, 705P, and 708P are active design while the 705i, 708i, and M2 use external amps and crossovers.  Picking the right model is a matter of desired ultimate spls, use of a sub/external amp-crossover, and primarily room size. 

The 705i/708i (i for installed) are intended for multi-channel setups.  The 7 series like the M2 use a special compression tweeter.  The 705P/708P (P for powered) was the last in the series to be released after studio folks asked for active versions.  In this case two 250 watt class D amps.  The 705P/708P also has a myriad of DSP functions built-in:  DAC, 4 PEQ/8 room EQ bands, frame/speaker delays, etc.  I’ve not experienced any of that (so far).

The 705/708 are meant for mid-field/open air use, which is how I use them, temporarily sitting on concrete blocks and pieces of 2x8 with thin/spongy drawer liner in between.  The room is 8ft x 13ft x 21ft (Cardas Golden Cuboid) and set-up is roughly an equilateral triangle, 6 feet to side, away from walls.  I have six GIK 244 panels but in this room are minimally effective regardless of how I’ve tried to set them up.  Source is my MacBook playing ripped CD’s from iTunes (ALAC) or Tidal.  Signal is processed by a DSPeaker Anti-Mode 2.0 Dual Core DAC/preamp/bass DSP unit that sits on a shelf spiked to the floor between the speakers.  Cabling consists of 10ft Straightwire USB and 10ft Best-Tronic XLR interconnects.  So a very minimalistic, speaker centric, system.  No sub used unless noted.

I’ve been into stereo/audio for 40+ years and listen primarily to small ensemble jazz/classical and old pop, but do have latin, rock, new age, religious, orchestral/symphonic on my plate.  The above room is a dedicated basement “study” (audio in front, office in back) and includes 3 bookcases on the side walls.  So the room is well shaped, treated, bass DSP applied, and insulated plus has 3 dedicated audio circuits one per cryo’d hospital grade duplex receptacle that are grounded together separately from the rest of the house (and the house has a dedicated transformer).  Appliances are all 13 years old or newer.

Was in the market for up-scale mid-field active studio monitors as I’ve listened to active speakers for 15 years (most of that time to single driver designs which are active by default).  Thanks to Audio Circle members Poseidonsvoice and Russell Dawkins both suggesting the 708P as being thoroughly modern with a solid American background, I snatched these up from jtwrace, taking delivery of them on July 25th. 

Other than these 708P’s the only other speakers in the family I’ve heard are the original 305’s (had them here for a week shortly after release) and recently an afternoon with fresh out of the box 305 Mk2’s with a couple of my audio club buddies.  The Mk2's were noticeably improved over the originals (more detail, tighter bass, better imaging).  While the originals were value leaders and did nothing wrong, they didn’t ‘light my fire’ however the Mk2's are quite enjoyable and would be very easy to live with long term.

But switching back over to the 708P's instantly makes you aware that they’re in another league, as I'd hope for 13 times the price!  Way more dynamic (good fun), much deeper/fuller bass, highly accurate transmitting the detail directly to the listener’s ears like headphones, and deeper/wider soundstage.  Plus the 708P's have all those DSP related features.   Adding a sub has really only helped with bass heavy music and added a sense of feel to that bass.

Have been playing around with positioning (moving them several inches at a time, not a believer in fussy speakers or making half inch changes).  A friend suggested facing them ‘straight ahead’ versus aimed at the listener, which indeed did help widen the soundstage beyond the speakers without losing the center stage imaging and softened the sometimes aggressive upper midrange experienced at higher spls. 

The 708P’s are indeed very serious working monitors, not speakers to be ignored or passed over for casually entertaining.  The size (17.35”H x 9.85”W x 12.30”D), weight (25 pounds), the large waveguide, permanently mounted woofer grill, and matte black finish with built-in side handles give warning to all that up front.  They demand your attention.  The overall sonic presentation is not for light weight sissies: they are more forward than recessed, hard hitting, and take no prisoners, yet are ruthless of only the poorest of recordings. 

The 708P’s project sound like not nothing I've heard before at home.  Volume levels are adjusted much more often due to their extreme dynamic nature.  So they’re addictive to play at higher levels but may sound best at lower levels.  They deserve the very best ancillaries (looking to upgrade my front end).  Colored gear would defeat the purpose of this reference studio monitor.  Listening to these reference studio monitors makes one realize that you may be hearing the recording better than anyone else has ever heard it before (in studio or home), they are truly State of The Art. 

[trianglezerius]

Nice write up, Jeff. 

[TomS]

You captured it very well Jeff 

When I first described my newly arrived M2's to Jason, the words "surgical precision" came to mind. They tell no lies, yet make the music completely enjoyable, a tough trick to pull off.

[Wayner]

James did not start ALL Techncal (Altec), he was actually bought out by ALL Technical in 1941. He also agreed not to do any audio business for a period of 5 years after the sale. It was after the sale that All Technical changed (shortened) its name to Altec Lansing (keeping the Lansing name for industry recognition).

The 708P is intended to be powered by a preamp or console.

[mresseguie]

Great write up, Jeff. Thank you. 

[dburna]

Thanks, JLM -- much appreciated. Thanks also for answering some of my specific questions via PM.

Question for everyone/anyone: not to hijack, but does anyone know if there are any substantial differences between the 705P ($999/ea) and the 708P ($1999/ea) other than the cabinet/woofer size and ultimate SPLs? I assume the amps are the same as is all the DSP technology, etc. If I have a subwoofer that I like, I am wondering if a 705P + sub configuration would give much/anything up versus a 708P standalone configuration.

Thanks, -dGB

[gab]

Thanks, JLM -- much appreciated. Thanks also for answering some of my specific questions via PM.

Question for everyone/anyone: not to hijack, but does anyone know if there are any substantial differences between the 705P ($999/ea) and the 708P ($1999/ea) other than the cabinet/woofer size and ultimate SPLs? I assume the amps are the same as is all the DSP technology, etc. If I have a subwoofer that I like, I am wondering if a 705P + sub configuration would give much/anything up versus a 708P standalone configuration.

Thanks, -dGB

dGB - Have you read through this thread? https://audiosciencereview.com/forum/index.php?threads/jbl-705p-708p.1303/

[Rocket_Ronny]

Great stuff and write up. Regarding the forward nature of the sound, I found the same thing with the SP Tech Minis which used a fair sized wave guide, as well as with a pair of Geddes Nathans, although to a lesser degree, if memory serves me correctly. At this point I am inclined to believe that wave guide speakers will come off as more direct and forward than non wavers. It must be how it propagates the sound waves into a forward sound beam.

I was wondering where in the world you find a used pair, but aha, from another audio fool junkie on this audio caste away ship. 

Myself, since I own a pair of wonderful Rythmik FM8 subs that play up to 200 hz very well I would go for the 705s and I doubt I would miss a beat.

Rocket Ronny

[dburna]

Great stuff and write up. Regarding the forward nature of the sound, I found the same thing with the SP Tech Minis which used a fair sized wave guide, as well as with a pair of Geddes Nathans, although to a lesser degree, if memory serves me correctly. At this point I am inclined to believe that wave guide speakers will come off as more direct and forward than non wavers. It must be how it propagates the sound waves into a forward sound beam.

I was wondering where in the world you find a used pair, but aha, from another audio fool junkie on this audio caste away ship. 

Rocket Ronny

Guitar Center had a used pair for $2200(!!) a little while back. You can check there and see if they are still there (doubt it).

https://www.audiocircle.com/index.php?topic=159022.msg1698609#msg1698609

Since these are usually sold as studio monitors, it would behoove thee to peruse the major gear websites (Sweetwater, GC, Musician's Friend, etc.) from time-to-time.

Best, -dGB

[dburna]

dGB - Have you read through this thread? https://audiosciencereview.com/forum/index.php?threads/jbl-705p-708p.1303/

I think I saw part of that a while back, but I should go back to the woodshed and re-research.

Thanks, -dGB

[JLM]

James did not start ALL Techncal (Altec), he was actually bought out by ALL Technical in 1941. He also agreed not to do any audio business for a period of 5 years after the sale. It was after the sale that All Technical changed (shortened) its name to Altec Lansing (keeping the Lansing name for industry recognition).

The 708P is intended to be powered by a preamp or console.

Currently using a DSPeaker Anti-Mode 2.0 Dual Core which is a DAC/preamp that also does bass DSP (4.0 volt balanced output). 

And the 708P has digital AES/EBU inputs so can be fed directly from a USB digital source such as a Tuscam UH-7000 (24 dBu professional output) or the soon to be released miniDSP SHD Studio (4.0 volt balanced output).

[JLM]

Thanks, JLM -- much appreciated. Thanks also for answering some of my specific questions via PM.

Question for everyone/anyone: not to hijack, but does anyone know if there are any substantial differences between the 705P ($999/ea) and the 708P ($1999/ea) other than the cabinet/woofer size and ultimate SPLs? I assume the amps are the same as is all the DSP technology, etc. If I have a subwoofer that I like, I am wondering if a 705P + sub configuration would give much/anything up versus a 708P standalone configuration.

Thanks, -dGB

I believe the amps are the same, seeing how class D is already small/efficient.  Pretty sure that the DSP technology is the same as the owner's manual is used for both speakers.  As the waveguide is smaller, the constant directivity effect would be somewhat reduced.  I wouldn't lose much sleep over the difference between 705Ps with sub versus 708Ps without (in fact I'd lose more sleep over spending the extra if buying 708Ps at MSRP).

[mr_bill]

Do you hook up an analog preamp output or digital output directly to each speaker - one channel to each speaker?  Do the speakers have to be connected to each other too for any reason?

[poseidonsvoice]

Jeff,

Only too happy to help you come to a decision to what I have always felt is the foregone conclusion: Properly designed wave guide based loudspeakers absolutely ROCK! 

Enjoy,
Anand.

[JLM]

Do you hook up an analog preamp output or digital output directly to each speaker - one channel to each speaker?  Do the speakers have to be connected to each other too for any reason?

 

Yes, I connect my preamp outputs directly to each speaker - one channel to each.  Too simple isn't it?  My system has 3 signal cables: digital USB into the DAC/preamp, right channel low voltage analog to the right speaker, and left channel low voltage analog to the left speaker with 4 components: MacBook, DSPeaker DAC/preamp, and 2 speakers. 

The JBL 708P has inputs for XLR (balanced, one analog channel) and AES/EBU (one digital channel).  So in a simple stereo setup you run one signal cable (analog XLR or digital AES/EBU) to each speaker.  There is no need to connect them together, but there is also a AES/EBU (one digital channel) output, so you could send the same digital signal to multi speakers. 

Most home audio gear use RCA (single ended) low voltage analog signal connecters that use two leads (one for signal and one for shared return and ground).  Professional gear uses three lead XLR or TRS (balanced) to separate the ground.  This allows freedom from grounding and RF issues.  So the 708P requires a preamp with balanced outputs (or a 'cheater' adaptor/cable with RCA on one and and XLR on the other end).

The other option as I mentioned above is to use something like the Tascam UH-7000 which converts USB to AES/EBU and digitally controls volume, then run a XLR style AES/EBU cable to each 708P and use the multi-purpose DSP (Digital Signal Processor) within the speaker to make the Digital to Analog Conversion (DAC).  This keeps the signal digital all the way until the analog outputs from each amplifier channel. 

Connecting passive speakers together was done by a couple of companies decades ago for "enhancing" the soundstage.  Lately it's been done mostly for powered speakers (where one cabinet contains a two channel amplifier, one for each speaker, with the connecting cable sending the high voltage signal to the other speaker).  Note that in powered speakers one channel of amplification powers both woofer and tweeter with high voltage (simple) crossover splitting the signal between drivers just like a traditional passive home speaker.  Audioengine speakers are examples of powered speakers.  They have the advantage over traditional passive speakers of saving the separate amplifier cabinet but schematically (electrically) are the same.  One disadvantage of this design is that one speaker has a longer speaker cable and the other has a very short cable inside the cabinet.

[dburna]

Alto Music on Amazon is selling the 708P for $1298/ea (under $2600/pr.). Wowza.

https://smile.amazon.com/JBL-Professional-708P-Bi-Amplified-Reference/dp/B01N28EKMS/ref=olp_product_details?_encoding=UTF8&colid=NCRYXBNXTFCV&coliid=I24FTNE3OBPB0Q&me=

Enjoy, -dGB

[cloudbaseracer]

Any thoughts on how these would compare with my Gedlee Abbeys?  Is it essentially the same or is the Geddes Waveguide superior in any way?  It is definitely shaped different.

Cheers,
James

[JLM]

Thanks for the question James.

Had the opportunity to visit Earl Geddes and hear his 7.3 system a couple of months ago during a local audio club meeting.  Unfamiliar with the music, so hard to compare but his room was very similarly sized/shaped and otherwise designed to mine.  Overall, being a proud papa, I'd say that I'm very pleased with the 708P's.  Amps were both Harmon/Crown, but his system was optimized for video (front speakers behind the screen).  Earl is a self-professed movie hound.

Circular shape of waveguide is superior in my mind only if you need to lay the monitors on their sides or you listen laying on your side as the relatively wide dispersion of the JBL waveguide better suits side-by-side human ear orientation and most listening space dimensions (wider than tall) which in my understanding would support the whole purpose of controlled directivity (to limit room interaction). 

[jtwrace]

People that are interested in the 708P might be interested in these links.


https://www.sausalitoaudio.com/wp-content/uploads/2018/07/JBL-708P-Charts.pdf


https://www.sausalitoaudio.com/wp-content/uploads/2018/07/Interpreting-Spinorama-Charts.pdf

[witchdoctor]

I can't understand why anyone would not want to replicate what the engineer heard in the studio. So simple and cost effective.