Fast, fun, Inexpensive OB project

[dawa]

Hi John, I need advice concerning the big iron coil for the Peerless.

I am trying to find an iron coil in Europe and it seams that 18 o 22 mH are sort of standard here. But I did find some Janzen C-coil 20.00mH 5% rdc-0.29 10% wire-1.40/ 800 Watt 8 Ohm and the more expensive: C-coil 20.00mH 5% rdc-0.18 10% wire-1.60/ 1500 Watt/ 8 Ohm.

Would they work?
DaWa

[John Busch]

Hello DaWa

The Manzanita can work well with anything from 16 Mh up to 22 Mh. Sweet spot is 18 to 22. Above 22 no additional advantage. It is best to keep the DCR below .6 ohm or so. Your Janzen selection should work well. The lower DCR may require a slight adjustment of the high pass R2. I would use 5 ohms to start with and if you feel the high end is not as bright as you would like, then try 4.5 ohms. It seems the Latest Vifa's are a bit hotter than the earlier production runs, so it seems 5.0 ohms for R2 and 15-25 ohms for R1 seem to be a better balance for most listeners. Please let us know what ends up working for you. John

[dawa]

Thanks!

Well i did test a setup with the sls 12 and my ss2905 activ filtered with the Minidsp. It works but the bas output is not what I expected. I have tryed Eq but I have decided to go for the latest Vifa edition instead!Dawa

[John Busch]

Hey DaWa

You kinda caught me sleeping, forgot you intended to try the SS 2905. Part of my previous post had the Vifa in mind, which of course would not apply directly to the SS 2905.

Can you tell me what about the bass output that you did not expect? Amount, quality, low end extension? How did you have your Mini-DSP set up?

John

[dawa]

Well I sort of followed all sugestionds but ended up a little like Rudolf sugested a 1220 lp for the woofer and 1350 hp for the 2905. A little Eq at 100 Hz. Then meassure and adjust the amplification on my bas amplifier so I get a "flat" response. Sounds ok but lacks the "slam". I think what You do in the passive filter is not so easy to replicate in the digital filter. So I will go for the original Vifa design and make a comparisson./Dawa

[Pano]

A 1220 LP on the woofer won't work right on OB. It needs to be much, much lower to fight the rising response.

[jcowling]

Finished my Manzanitas. Wow. Sounds great. A little harsh, but everything needs to break in.
First observations: needs some power. My 125 watt per channel amp is keeping up, but it sounds like I need all of it.
I moved them closer to the back wall - 3 feet - sounds more balanced.
Lots of detail and lots of bass. The midrange sounded a little weak at first, but is starting to come out.
Vinyl with my phonoclone 3 is shining big time. The bass is tight on most tracks and the percussion has impact. Vinyl puts my Squeezebox with the rDac to shame.
I think everything will clear up in general with some hours of break-in.
I bow down to the incredible design of the Manzanita. To achieve this quality and sophistication with such a simple design and such inexpensive drivers is amazing.
John

[shortwave]

I continue to be really happy with the way my speakers sound (Thanks again John). I have yet to solder everything point to point and was pondering the final layout of the crossover when I notice the leads of the iron core inductor buzzing with vibration. I also happened to also read an article regarding passive crossovers and more specifically behavior of inductors and soaking them (the coils) in varnish to hold the wire in place and eliminate any buzzing and or vibration. Does anyone have any experience or comments with doing this?

[Pano]

Thanks John C for the glowing report. Yes, they do need power - that's the trade off for decent bass out of a mid size OB. No free lunch. John B's designs usually have what sounds like a recessed midrange, but don't all measure that way. Maybe were just used to speakers with a midrange bump.

If the Manzanita is harsh, you may need some crossover tuning. John B can jusmp in there with some hints.

[jcowling]

Originally Posted by Pano

Thanks John C for the glowing report. Yes, they do need power - that's the trade off for decent bass out of a mid size OB. No free lunch. John B's designs usually have what sounds like a recessed midrange, but don't all measure that way. Maybe were just used to speakers with a midrange bump.

If the Manzanita is harsh, you may need some crossover tuning. John B can jusmp in there with some hints.

I grew up with bookshelf speakers, so you may be right that I am biased towards more midrange. The harshness may just be a function of no break in time and that the material I played first, Richard Thompson's Hand of Kindness, is a little harsh sounding with lots of reeds and screaming guitars. The temporary stands were also too high. I cut the wood for the proper height stands, but have not put them together yet. There was no way I could wait for the stands to be done to fire up the new speakers!

I will get some more playing time on the Manzanitas and move them around in different rooms before I start thinking about tweaking the crossovers.

Thanks for all the help from you and the other forum members. I studied many of the pictures in this thread to help with the crossover layout and wiring and it looks like I got it right the first time (something that I am not used to with my marginal DIY skills).