DIY Audio Projects Forum

For OB design you need big drivers to get reasonable bass weight. Therefore 10".

_________________
Projects: "Grace" - Psvane 6SN7-SE Globe preamp | | "VoXUno" - Single driver MarkAudio 12P speaker | | "Lagoon Take 2" - Single stage tube preamp | Website: retro-thermionic

I don't want OB. I prefer MLTL or Bass reflex. But it's can't make decision

If you have some experience I'll be really appreciate

Thank you
Alex

You are posting in an OB thread. It may be best to start another.

_________________
Projects: "Grace" - Psvane 6SN7-SE Globe preamp | | "VoXUno" - Single driver MarkAudio 12P speaker | | "Lagoon Take 2" - Single stage tube preamp | Website: retro-thermionic

The exception is if you have "Room Gain".

I've heard some 8" FR's (Hemp Acoustics) sound pretty good in a room that lucked out and resonated at about 40Hz

Cheers!

_________________
-= Gregg =-
* Ratings are for transistors - tubes have guidelines*
Home: GeeK ZonE
Work: Classic Valve Design

Hi all

Like to go back to the start here and thank the Author for his design. It really rocks.
With the right amps of course.
Built pretty much as explained but with options such as a switch and PO9.Xover input.

Any interest will publish more here. Few pics for now.

Dave

Nice build. Looks smart.

_________________
Projects: "Grace" - Psvane 6SN7-SE Globe preamp | | "VoXUno" - Single driver MarkAudio 12P speaker | | "Lagoon Take 2" - Single stage tube preamp | Website: retro-thermionic

Hello Davesatu, first of all thank you and author of this thread for all the informations and showing the speakers which you built guys...they are great ! I am in the beginning of all the process to build these speakers. I am from uk and now because I am an amateur can I ask you guys what exactly I need to buy to build such a speakers ? I know I need 2 x Dayton PS220-8, 2 x Eminence Alpha 15 woofers, but what else ? Can you show me a list what else I need to buy to build them please ?

Best Regards,

Rafael

Hi Rafael. Sorry for the delay in replying to you as I am in the middle of building and testing 3 separate SET amps. The first two are finished now being a nice 2A3 and the JE Labs 45 (pictures available) with some adds to fix a hum problem. All magic so far. The 45 wins now. Last is the Morrison base 300B. Again with some mods to suit me and my 30 years of making mistakes first time. So that's the background.

Getting back to the OB's yes they are superb with most music. The beauty is you can dial the bass from the plate amp. Which can help with your room acoustics a lot. As well as vary the Xover point and listen for your best setting. I have driven these speakers with the tube amps above and a TS CFA all of which are only 2-3 watts. Fills a big room well.

Sorry I can't give you a parts list. Surely doing that is part of the DIY experience. What I do have is the PCB board for the notch filter. The Author is correct - this makes a big difference.

hope this helps
Dave.

Hello Dave, thank you for your reply. I appreciate it a lot. Congratulations as well on building your own amps...thats impressive.

One thing I was curious was plate amp for eminence alpha 15...are you usung dayton sa100 plate amp or a different one ? Also will dayton sa100 plate amp delliver enough power for these eminence alphas 15 ? Once again thank you for your answer.

Best Regards,

Rafael

Hi Rafael. No I needed a 240 volts plate amp here in Australia. So it is a local probably Chinese made one 120watts. Any between 100-200 watts will be fine. As long as it can be set for level and crossover point. Mine can be crossed anywhere between 40 and 180Hz. Sounds best at 140.
have fun
Dave.