[Freemand]

I can't believe less then a week ago I introduced myself in this circle with kind welcomes and screamed about my excitement of getting my first open baffle speakers.

I talked about how I wanted to get a commercial set of OB first and then build later. Well, thats changed! I want to build my first set of OB. I have been studying this open baffle circle and have learned a lot more since my first post and introduction. I also believe if done right you can get much better results building your own OB then buying a commercial pair at the same price points.

My question is to your all is what avenue to go down when doing a diy OB?

1) Buying a kit. I have been talking to Darrel and Dianna at Hawthorne and am impressed with them. They have a new amt tweeter thats replacing the 700 amt and is suppose to be better. Then they have an 8 inch driver along with using an augie. The passive crossover is all point to point with quality caps. Sounds like a great combo. Theres also pureaudioproject but I dont think the tang mid tweet is as good as the new amt thats out from Hawthorne. These are some of the kits along with others not mentioned that has the work done via the driver and crossover done for you.

2) Is buying various drivers and making my own crossovers. Not sure if that can be a better result considering Darrel at Hawthorne for instance has done all the work. The problem with this route is I don't have the experience of building my own crossovers and trying to match drivers and the time it takes. I would have to follow and copy a proven result from this circle.

3)Active to passive crossover is another big consideration. I like the idea of the flexibility of active but the ease of passive.

Knowing my system may also help with the passive or active crossover decision. I am using an NAD m51 as my preamp using its 35 bit volume control and digital hdmi in which feeds my Oppo 103d. This of course, allows for good DAC conversion via blu ray and sacd. I also use a flash drive in flac in my Oppo for redbook. My amp is a Pass Labs xa30.5 which love the tube like sweet midrange. So the NAD to Pass is a combo I don't want to part with.

Which is what scares me about active and using cheaper pro amps with dsp like a Crown. I just love the sound of the Pass and don't want to buy two more Pass labs amps and minidsp to go active . A bit expensive!

So theres my story! I want to get on this OB train and ride it to utopia but how I get there is unknown??

 

[gab]

start here:

http://www.diyaudio.com/forums/multi-way/110583-fast-fun-inexpensive-ob-project.html

The Ultra (post # 1054 on pg 106) would be a good one to start with. I have heard the commercial version at LSAF a few years back and was impressed. Have fun!

gab

PS - your 30W Pass amp should power the Ultra just fine (IMO)

[ebag4]

I would look at the GR Research circle on this site.  Danny is a master designer and has had quite a few OB offerings.  I have built 4 of his designs (one being a box speaker for my sister) and all have been outstanding.  The servo sub OB bass he offers cannot be beat IMHO.  I am currently running his Wedgie, it is the best speaker I have owned in the past 35 years I have enjoyed this hobby.  Unfortunately there is an issue with the availability of the tweeter he uses for this speaker due to the manufacturer being purchase, but there is hope it will become available again.  You owe it to yourself to give Danny a call before making your decision. 

I have also built an early set of Hawthorne OBs, you won't go wrong there either.

My recommendation is to go with a proven design, at least for your first build, then if you have the tools to design your own go for it.

Best of luck,
Ed

[Freemand]

I should also note, that running a tweeter like amt or a neo 10 panar for example over more traditional tweeters is appealing. I have heard about the goods on Raal's. I am also willing to pay more to get the best drivers to build this and start with something that I wont have to change anytime soon cause of an upgrade itch.

Gab, the driver for handling the highs one the diy link you sent don't seem like its that efficient.

Ebag4, I have liked what I read on GR research and they work together with Hawthorne. Question is, who has better drivers? I like what I have seen with Hawthornes newest amt that replaced the amt 700. But then again, what do  I know!

I do plan on talking with GR.

[gab]

Gab, the driver for handling the highs one the diy link you sent don't seem like its that efficient.

Freemand - the Ultra is spec'd at 86.5 db/ watt @ 1 meter mid-band, 8 ohms nominal.  15 watts RMS minimum

Here is a link: http://manzanitaaudiosolutions.com/ultracv.html

Only you will know if that is enough (room size, listening levels, music genre, etc)

Here is a link to the Manzanita CV which John had at RMAF a few years back: http://parttimeaudiophile.com/2013/10/24/rmaf-2013-manzanita-audio-solutions/

Also no issues with GR Research either. I own a pair of modified Super-Vs with matching center channel in my home theatre!

Best of luck whichever path you take.
gab

[Joemamma]

Combination of Danny's Wedgie and open baffle subs are the best I have ever heard.  There is just no comparison.   They are a game changer.  It makes you wonder why people still listed to regular boxed speakers.  The bass from those open baffle subs is incredible. 

[Freemand]

I have been over on the GR research website again but looked deeper into the site this time and do not see anything called wedgie. One problem I saw is the designs dont seem to be full open baffle as many have full or partial box.

Then manzanitas look nice considering the very low price the drivers cost to make it perhaps giving it a big bang for the buck.

The efficiency is to low with the amp I am using. Its 86 db where as the one by hawthorne mentioned above is 98 db

[ebag4]

It hasn't made it to his website yet, this is where it started:
http://www.audiocircle.com/index.php?topic=126112.0

The older designs had a boxed bass section, he has had several designs that have full OB.

There are several other threads in the GR Research circle talking about the Wedgie as well ia newly designed bass section for it.

BTW, the Wedgie is about 94dB efficient.

Best,
Ed

[InfernoSTi]

1) Buying a kit. I have been talking to Darrel and Dianna at Hawthorne and am impressed with them. They have a new amt tweeter thats replacing the 700 amt and is suppose to be better. Then they have an 8 inch driver along with using an augie. The passive crossover is all point to point with quality caps. Sounds like a great combo. Theres also pureaudioproject but I dont think the tang mid tweet is as good as the new amt thats out from Hawthorne. These are some of the kits along with others not mentioned that has the work done via the driver and crossover done for you.

My amp is a Pass Labs xa30.5 which love the tube like sweet midrange. So the NAD to Pass is a combo I don't want to part with.

I am gloriously happy with my Hawthorne Audio Reference Series K2 speakers using my Pass Labs XA-30.5 amp.  Complete satisfaction.  The smaller series uses a variant of the AMT in my speakers and that is the heart of the speaker.   

Perhaps visit with EarlyB on these same forums for his thoughts?  http://www.audiocircle.com/index.php?topic=134269.0

John

[JLM]

Pick the speaker for the given room (especially important for O.B.).  Too many gear heads overwhelm the room.  (I've done it in my younger days.)

Pick the amp for the speaker (speakers have more character/variables).  Your Pass amp is miles ahead of any Crown amp.

Ideal efficiency is around 94 dB/w/m for a balance between good dynamics and not hearing system noise (grounding hum/tube rush/etc.).

For your first time, go with a kit from a trusted source.  Darrel is a good guy.  Danny really knows his stuff.  Either would be good.

If you have lots of DIY blood in you look for a design that upgrades easily.

Active (one amplification channel per driver, crossover upstream of amps) has huge advantages over passive.  15 years ago I auditioned Paradigm Studio 20 (typical $800/pair 2-way stand-mount passive) versus Active 20 ($1600/pair active version of the same speaker) - no contest.  The Active 20 was amazingly dynamic, incredibly flat frequency response (a revelation), and had unbelievably deep/full bass.  Passersby were gobsmacked, thinking we were listening to the Studio 80 ($2000/pair large floor-standers) but the imaging was better.

[mcgsxr]

i agree with many of the excellent suggestions here.

I'd start with a kit for my first build.  It more likely ensures a positive outcome for your efforts, and will help you ID what you might want to do differently.  When you select a kit, you often inherit a ton of experience from others, forum support, and perhaps even access to the designer.

Darrel vs Dannie?  Pick your exotic car reference of choice, both build excellent stuff, have a strong following and having heard offerings from both I would say either will provide excellent sonics.

JLM is on the money too when he references room size, speaker efficiency and amp pairing ideas.

Good luck, the hardest part will be deciding which flavor you think will tickle your fancy the most!

[Freemand]

Thanks guys, appreciate all the advice and support. Makes taking this on easier when being steered in the right direction by those with experience in this area.

The Hawthorne and GR path is seeming to make sense. The wedgie is something that caught my eye as I started digging into that thread last night, however will be a more complex and tougher build, but may be worth it.

I should have mentioned room size JLM which is about 18 x 18. The room is loaded with treatments and my current speakers disappear.

If I did go active as JLM talked about how would I do that having the pass and loving the pass. Do I get a plate amp or dsp crown for the bass and keep the pass on the mid tweeter amt? I am reluctant to bring in cheaper amps for the sake of being active. I think If you do it right you get all higher end amps to pair with the Pass. Thats my thought??

It was mentioned to build so it can be upgraded easily. Elaborate on that if you could please so I grasp deeper what you talking about.

I will dig deeper in this tonight when I get home as I enjoy a fine aged cigar and a glass of wine on my back porch. Is life not grand! Fine cigar and audio researching and chatting all at the same time.

[bladesmith]

You cant go wrong using a 15" woofer in your open baffle.
 

[Freemand]

I spoke today With Danny at GR research and was a pleasant man to speak with.

I would say he concurred my opinion of where I may go with this diy project using either the GR research wedgie design or the Hawthorne design with the new amt and 8 inch driver augmented with an augie. These seem to be the top choices for the open baffle diy kits.

The problem with the wedgie as you can read in the thread discussing it is the availability of its tweeter which is unknown. This is a shame reading the ability this kit can do and leaves the Hawthorne design as the ready to be build now.

[bellicon]

I talked about how I wanted to get a commercial set of OB first and then build later. Well, thats changed! I want to build my first set of OB. I have been studying this open baffle circle and have learned a lot more since my first post and introduction. I also believe if done right you can get much better results building your own OB then buying a commercial pair at the same price points......
......Active to passive crossover is another big consideration. I like the idea of the flexibility of active but the ease of passive.........My amp is a Pass Labs xa30.5 which love the tube like sweet midrange. So the NAD to Pass is a combo I don't want to part with......Which is what scares me about active and using cheaper pro amps with dsp like a Crown. I just love the sound of the Pass and don't want to buy two more Pass labs amps and minidsp to go active . So theres my story! I want to get on this OB train and ride it to utopia but how I get there is unknown??

 

I am gloriously happy with my Hawthorne Audio Reference Series K2 speakers using my Pass Labs XA-30.5 amp.  Complete satisfaction. the heart of the speaker.

Thanks for these excellent posts Freemand and InfernoSTi. Did you build or buy your open baffles?

Are they active or passive? If passive, did you drive them with your Pass Labs XA30.5 amp?

If not, do you use the XA30.5 amp to drive other speakers? Which make/model?

Speaker impedance, sensitivity, room size and preferred average listening levels will, of course, impact this, but after the amp's required one hour warm up for best sound does its front panel ammeter stay centered or does it drift to the left or right? This can happen if you play the system fairly loud, if the recording has a good number of high dynamic peaks and/or bass down to around 30Hz.

Of course if the XA30.5's meter usually remains deflected away from the center position then it would have essentially moved from its Class A and into the Class AB bias region. If this happened with one or more of kinds of speaker pairs, do you recall which speakers caused the meter to move the farthest away from the center?

How does the meter’s needle usually behave with your Hawthorne K2 References OBs?
http://www.hawthorneaudio.us/docs/RainierAnnouncement.pdf

Did you ever notice with the Hawthorne K2s, driven by the XA30.5, that if played at very low listening levels (i.e. late night sessions)-BUT to where you still get very good bass response-that the overall sound seems sweeter, warmer and/or more detailed than when played at your normal levels?   

And did you ever find that the temperature of the XA30.5 chassis varied depending on the speakers you used and/or how loud you played them?

Is the chassis as hot to the touch as other Class A amps you may have used?

Also, do you use the front-panel standby mode all of the time between listening sessions, or do you often power the amp off using the rear panel switch?

Sorry for all the questions about the XA30.5. It’s one of the amps on my short list, but even though its been out for at least seven years I’ve never found anyone in the Long Island or NYC area who has one to ask for a demo.

So your detailed replies would be extremely helpful. Thanks in advance!

[Freemand]

Hi Bellicon, I have not bought any open baffle speakers yet as I over analyze any kind of big change to my audio system.

I was big on the Hawthorne speakers till I discovered everything I read on Spatial. I have also a big interest in Pure audio Project and have been chatting with Ze'ev for the last month. I believe I will either get the Spatial M3 turbo or Pure Audio project A5000 wolf van langa field coil or Voxativ. Since this may be my main speakers for a decade or two I may go all in and get the A5000 field coil. Its three times the price of the Spatial M3 turbo but should be a big sonic improvement with the wolf van langa field coil.

I think you will love the Pass labs XA30.5 amp. I went from tubes to this amp and did not really notice a difference (tube to solid state) which was like still using tubes. When I went from tubes to other solid state amps it was noticeable and lost that tube lushness. The Amp has to be the most stunning looking amp I have ever laid eyes on. Kinda like looking at Miss America!   

Keep us informed what you do.

[brad944911]

Freemand,
  I went down the DIY path a year or so ago and I still love tinkering...but make sure you have time.  I cannot say enough about using active crossovers, eq and DSP.  I would've went BROKE buying components for every change I wanted to just try.  Look to miniDSP...DSP in a box in particular if you go active.  With that level of processing, you can make your speakers fit YOUR room.  That will require tinkering and measurement equipment however.
  DIY OB speakers can sound AMAZING in any well implemented configuration and allow so much modification that the miniDSP will likely be plugged into your laptop permanently   
  I can't recommend any kit as I spent sickening hours researching theories and just built my own based on what I learned.  I learned a HELLUVA lot but surely only scraped the surface.  One thing I did learn: too many times there were competing "opinions", unsupported by research or facts, that have many angles and just as many devotees...sometimes just too zealous!
  No matter what, enjoy the journey man.  If you have solid woodworking skills and a shop...the enjoyment of engineering these may be just what you want.  If not this may get frustrating!
Take care bud,
Brad

[Freemand]

Brad,

What drivers did you end up going with and what made you choose the drivers you have?

I do love tweaking so the active crossover always sounded fascinating. Kinda like when I was 14 years old and bought a quality equalizer at a high end home audio store (back when there where audio stores!) and was able to hear what playing with all the different frequencies would do to the sound. I am surprised I did not wear out the controls of the equalizer by playing around so much. I remember hearing a live band back then and then went home and tried to set the equalizer to sound as close to that live music as I could. It was at that time when I realized the purpose of the audio system was to sound as close to live music opposed to simply playing music and being really loud.

[brad944911]

  Yup...did the same...back when TEAC and Bose were the bomb.  I nearly destroyed my AR's with one of those dynamic range expanders.  Anyway....I grew up, too 

  I started out using Matavena's(Ed's) original Hestia and while it sounded good with the passive crossover, I know there was more to be had from this whole open baffle thing.  After reading Linkwitz' site and a few others I decided active was the way to go...mostly to adjust to an imperfect room.  I immediately bought 3 Crown CDi 1000 amps and started messing with them and things got better with the Hestia's.  But I wanted more still.  I did so much research and brainstorming and eventually came to the conclusion a 4 way active system was what I wanted to go with.  Here's a link to the build: http://www.audiocircle.com/index.php?topic=143418.0.  The speakers were: Woofs - MCM 55-2891's(from the original Hestia) / Mids - Dayton RS100-8's / and Aurasound NSW-1's--2 each per side.  The subs are Boston Acoustic (car audio) 15's in a U-frame.  I chose the sizes based on the dispersion characteristics based on their SIZE.  I wanted as broad as possible dispersion per speaker as possible and crossed them over at roughly 2/3 of each speakers diameters equivalent wavelength.  Each band has it's own amp, so everything is adjustable.  If I had it to do over, I'd go the way of the miniDSP. 

  I had some lofty goals as far as dispersion of each driver and maintaining as close to possible to a dipole response I could...not to mention the frames.  I got lots of good advice from several of the members here and at this point I'm VERY happy with the sound.  Unfortunately I can't back up anything with FR plots or anything.  I bought a Behringer DEQ-2496 EQ and let it do equalization for each speaker based on the room's characteristic, so according to the EQ, the curve is flat around 20 degrees off axis either way.

  I can tell you from my experience as a serious tinkerer and enjoy woodworker, you'll likely end up building more than one after your first.  Crossover components for one multiway design can easily cost more than the miniDSP does...depending on what slope you're using of course.  Let's not even mention the exacting science it takes to get x-overs right.  Just my experience and I'm sure many will disagree with my approach, but it works for me.

Keep us posted man and enjoy this crazy journey...the sound is truly amazing when you get it right 
Brad

 

[Freemand]

Its easy to argue the benefits of both active to passive crossover. If you go passive I believe you can reduce some of their negative effects. I like what Hawthorn is doing with the passive crossover using quality components and point to point connection of the crossover components. I also like the Pure Audio Project Leonidas approach to the passive crossover with the gold plated screw terminals with quality caps and the ability to voice the crossover by switching the  components on the crossover. Only passive crossover I know that allows some tweaking.

Of course, going without a crossover has many advantages we all know of.

Sounds like you found some magic Brad! Cant imagine the amount of time you have put in, but is that not why we are here and self confessing audiophiles.