[FullRangeMan]

I always wish to know how tha Alpha and B200 would work together without the usual inductor, so for guidance to myself I paste these 2 charts into 1.
So, I thougth other audiophiles would like to see this graphic to have one more info to consider.
Please see below, ALPHA & B200 charts for reference:

[FullRangeMan]

Now the unified chart: Obviusly there is a strong midrange here.

I would appreciated read yours comments about how they both work together/direct in serie or parallel, without the 4,7mH inductor.
Thanks

[JohnR]

I'd never seen the Alpha 15 plot before, that explains why people say "don't use it above X Hz." You might be able to smooth it out with a notch filter, but running both drivers up past 2 kHz will result in a lot of vertical lobing. I'd say stick with the inductor...

[mcgsxr]

Personally, the highest I would go with the Alpha would be around 500.  That way, with 12db/octave, it should smooth right out.

I have driven the b200 down to 100Hz with much success, so it really is up to you.

[FullRangeMan]

Hi,
Anyone knows If the B200 & Alpha Freq Chart on post 1 was made with OB panel or in a boxed enclousure??
Thanks

[Rudolf]

Hi,
Anyone knows If the B200 & Alpha Freq Chart on post 1 was made with OB panel or in a boxed enclousure

The B200 was measured in this box:



Baffle size is 25,5 x 50 cm. For more info see http://www.visaton.de/vb/showthread.php?t=12754

[FullRangeMan]

OK, Thanks Rudolf for this info. These seems a big box.
I was thinking if the Alpha was measured in a BR box and the B200 in a OB panel, the combinated response could be as below:

[-Richard-]

Hi Fullrangeman ~

It has been quite a while since I posted on AC. I am currently using a very inexpensive 8" driver in place of the B200's... the Dayton Audio PS220-8 8" Point Source Full-Range Neo Driver / http://www.parts-express.com/pe/showdetl.cfm?Partnumber=295-346&FTR=dayton%208%22%20full-range%20driver (from Parts Express). They are now $94 each.

It has a built-in phase plug that looks like a medieval lance (is that the "neo") and a "parasitic" high frequency cone. I have it crossed-over on the 15" Alpha at around 350 Hz... using a simple coiled inductor... the same cross-over I used with the B200.

With Warmest Regards ~ Richard

[FullRangeMan]

Thanks Richard for your kind information on this Dayton driver.
Unfortunately for some reason, PartsExpress do not sale to my country.
Do you had the freq chart of this driver?? It specified til 25kHz...
I would like your impressions regards B200 vs Dayton.
Thanks

[-Richard-]

Hi fullrangeman ~

Yes... both the B200 and the Dayton "retro" 8" wide-range drivers are "entry level" drivers that can teach us a great deal about the potential of the Open Baffle "experience".

For me OB meant the end of audio-hype... the end of lusting for expensive speakers that claimed to deliver the "goods". They may do some things well, but they are inferior to the simple OB paradigm.

So entry-level is no small thing... it is a mind-changer... an awakening to the truth that we can have an intense musical experience for little money and Do It Ourselves.

But the B200 or the Dayton are not the last stop on this journey. I purchased the Dayton retro because it looked like an expensive driver... meaning it had the phase plug, the high frequency wave-guide "cone" and the spec's are not that far away from being applicable to OB use.

What I heard after playing the Dayton retro for a day or so was a much clearer presentation.... the high frequencies were cleaner and much more "there"... much better resolution than the "softer" and somewhat rolled-off B200's. There is more "air" in the Dayton's as well and they sounded more musical.

I should go back to listening to the B200's now that I have listened to the Dayton retro's for perhaps a year... to see if my impressions are accurate. I no longer trust myself with anything to do with audio... it is all much too subjective.

Dan Mason many years ago used to say that a hemp cone matched with an Alnico magnet should bring us close to perfection for OB use. And that is probably still true.

I am looking for that perfect and inexpensive driver. If I find something close I will write about it. Too bad my budget reflects the actual state of the general economy in this country... "depressed".

With Warmest Regards ~ Richard

[FullRangeMan]

Dear Richard,
You most kind, I appreciated so much your report, Thankyou.
Cause I never pay attention to this Dayton, I thought it did not apply for OB because low QTS=03, but seems it work.

I found Impedance and Freq Chart at the manufacturer site:
http://www.daytonaudio.com/media/resources/295-346-dayton-audio-ps220-8-brochure-9530.pdf
The Phase & Impedance curve are very good.

Looks hemp cones are no more currently, since HempAcoustics close, but Nirvana cones use Kratf paper, also very musical, and David sell a entire line of Alnico fullranges.

Do you mean say you get these good result only with a 4,7mH inductor or are you using EQ or DSP??
Regards

[opnly bafld]

http://www.abrown.com/

[FullRangeMan]

The Dayton 3 - 4.5kHz peak is bad, otherwise response is good.

[SteveRB]

Richard,
glad to hear your response. It is easy to get lost down the path of more money equals better sound.

I have an inexpensive vintage alnico driver that was 'blessed' by Dan Mason. Sounds fantastic. I am always on the hunt for other interesting vintage drivers.

[-Richard-]

Hi FULLRANGEMAN ~

I am aware of David Dicks line of Alnico drivers.

I actually heard David's 15" Alnico by itself in a simple slab-of-mdf Open Baffle panel at another "designers" house in LA... his gear, which he sells, is all "digital"... I thought Deborah and I would jump out of our skins at hearing this set-up... it was extremely painful!!!! Glassy, steely, overly zapped, hot high end, muddy everywhere else... and LOUD... DID I SAY L-O-U-D!!!!!! OK... this is how many young audio enthusiasts like their music... loud and "intense". No problem. I was actually impressed with David's 15" Alnico... it had real bass and detail. I could not tell how the mid-range sounded... too much digital noise screaming at us. I know... I know... why didn't I say something to this chap? Well... we did... but he insisted on playing his "special" music to show us what his system can do... and his "special" music was thundering pulsating drums and powerful thrusts of tonal chaos. No problem. We love all music. But it is impossible to hear anything "critically" that would allow me to understand better what David's speakers where doing... impossible to separate the speakers from the "source".

Thanks for the graph on the Dayton. Flat seems to be something a great many DIY "designers" want to see in their drivers... it is universally accepted that flat equates with "neutral" or uncolored. It is like meeting someone and first looking at their IQ to see if they are intelligent or not... or using some other "measurement". An amplifier designer I know designs his amps strictly by looking at the waves on his oscilloscope... he distrusts his "ear" entirely.

We are a society that has been conditioned (trained) to no longer trust our own "natural" impressions about anything... that is why we "trust" and seek out experts. And that sets us up for all kinds of silliness not to mention losing our confidence to "know for ourselves." Listening is the essence of intelligence... listening is intelligence. And all of us can listen for ourselves to establish an understanding of what works and does not work in audio.

Today the Dayton's and the 15" Alpha sounded incredibly "there"... immediate, musically detailed, richly textured, plenty of "air" and space. I am not using a tweeter so there is probably not what many refer to as "sparkle" on top... and I don't miss it. But the "tone" is there. Surprisingly.

I am listening in a new way to my set-up... I am trying to "hear" if I need to upgrade my drivers. If I feel the need to upgrade I am going to go for a pair of field-coil's. But the set-up sounds so good with the dayton and Alpha driven by the old Heathkit (even though the old volume control refuses to work consistently).

I am not using EQ... although if a decent piece of gear fell from the sky into my audio listening space I would set it up and experiment with it. I just use a simple C-coil inductor 4.70Mh from Parts Express. What worries me lately is that my two 8 Ohm drivers hooked-up in parallel present a 4 Ohm load to my 7 watt amplifier. Won't that stress this tube amp too much? I haven't tried hooking it up in series yet... my understanding is that would halve the amps output (to 3.5 watts?).

Hi Astronaut_glen ~

Yes... audio has become yet another snob-appeal item, cleverly fashioned by magazines and audio shops into "classes" of products... audio "jewelry" that lingers in the mind like splinters that we can only scratch with money. There are terrific audio possibilities of course for cheap... like DIY Open Baffle speakers. For amps, used is probably the way to go... unless you "love" something and you cannot find it used and so one "goes for it"... why not? The younger generation (kids) have entirely redefined audio around computers and internet radio... they burn each others CD's and share. They will survive the spend-until-you-have-no-more-to-spend culture by their resourcefulness... bless them. They are showing us the way.

Please keep in mind that Alnico (Aluminum, nickel, cobalt powder heated and magnetized) magnets need to be "recharged" every 10 to 15 years... they gradually lose their charge. In the olden days every audio shop had equipment for that... now one's drivers must be sent to a special place that does that. Alnico is also affected by extreme cold and sudden hits, like dropping them. That is why I am not inclined to buy an older Alnico driver... but I bet they do sound good as you have kindly shared with us.

With Warmest Regards ~ Richard

[FullRangeMan]

Richard,
Very Thanks for your first hand extensive report, very enlightening.

Dayton site info: http://www.daytonaudio.com/index.php/loudspeaker-components/loudspeaker-drivers-by-type/full-range/ps220-8-8-point-source-full-range-neo-driver.html

Dayton FR datasheet: http://www.daytonaudio.com/media/resources/295-346-dayton-audio-ps220-8-brochure-9530.pdf

Dayton FR Neo Motor test: http://www.daytonaudio.com/media/resources/295-346-dayton-audio-ps220-8-brochure.pdf

Seems to me the Fostex F200A eight inches Alnico, is a nice flat FR, a pity it no suited for OB.
About your 7W amp driving this 4 ohms load(and 3,75 ohms with the B200) is certain this amp is stressed, mainly If you listen in hi SPL.
BTW, I wonder how many thousands hours your output tubes are lasting in this situation??
This can be a good indicator of amp stress;

I could like to teste for some weeks the Alpha+Dayton connected in Series, to a tube friendly 16 ohms impedance.
Seems your 7W amp(8 ohms), could delivery around 10W in 16 ohms... but in 4 ohms it will give around 5W or less.

I would love read your impressions on the Alpha+Dayton connected in series.
Best Regards

[-Richard-]

Hi FULLRANGEMAN ~

I could like to teste for some weeks the Alpha+Dayton connected in Series, to a tube friendly 16 ohms impedance.
Seems your 7W amp(8 ohms), could delivery around 10W in 16 ohms... but in 4 ohms it will give around 5W or less.

I would love read your impressions on the Alpha+Dayton connected in series.
Best Regards

I have looked at several diagrams that clearly show how to combine 2 drivers in "series"... "positive" (+) of amps speaker cable connection to positive (+) of one speaker... then the negative (-) of that same speaker to the positive (+) of the 2nd speaker... then the negative of the 2nd speaker back to the negative of the amps speaker cable connection.

I don't see where I will be able to connect the inductor-coil?

The inductor-coil in the parallel connection I am now using allows for the speaker cable from the 1st driver (Dayton) to "pass through the negative (-) and positive (+) prongs of the inductor (the "outside" of the coil has 2 prongs (-) and (+) and the "inside" has 2 prongs) and then onto the 2nd driver (the Alpha 15").

But in the series connection only "one" wire goes from the amp to the speakers and back again(?)

I will contact Parts Express to see if there is a way to connect both drivers in series while still being able to use the inductor.

When I read spec's pertaining to SS amps the lower inductance (4 Ohm vs 8 Ohm) doubles the watt output. Admittedly this does not work in the same way with tube amplifiers which apparently do not "double" as the inductance is halved. But your suggestion that the watts would double if I connect the drivers in series is not clear, with this in mind.

Can you (or anyone) explain how that happens?

With Warmest Regards ~ Richard

[FullRangeMan]

Hi Richard,
It is not possible use a inductor in series connections, in series this drivers will be running direct by the amp.

On some SS amps the Wattage double when the impedance fall half, cause the power supply is big, as Krell, Levinson, etc... and all the circuitage is designed to be a power house.

On most tube amps the opposite happens, when the speaker impedance double the amp wattage up afew watts. And if the loudspeaker impedance fall the amp power also fall a lot, as usual on tube amps.
Cheers

[FullRangeMan]

A parallel connection with a inductor. In Parallel there is a +3dB boost over serie, theoretically.

[FullRangeMan]

A serie connection,