The WIBAQ: TABAQ Design with Betsy K

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Nop I did not build the BSC + notches, I ran a couple of simulations and the load is to heavy for my homebrew tube SE.

So I decided to stick with a Foobar EQ, and the amp see a "light" load, only the speaker.
I just finished to design an "hardwired" filter with AOPs, between the DAC and the amp for CD player.

I put stuffing in the WIBAQ, the sound is really "classy" but it lose his "live" mojo with no stuffing. Next week i will try more or less stuffing.

seb
 
Long time lurker of this thread.

I thought i'll add a short version of my wibaq journey.

Built my wibaq's a year ago. I went a bit too heavy using 22mm MDF. but at least it is very solid.

Only did the sanding and painting of the enclosures a month or so ago. ( my wife convinced me its time)

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Depending on who you ask they probably have enough bass.

It was a little shy for me. I'm running mine of a 30W per channel ultra linear tube amp.

I did a BSC with a simple resistor / capacitor in the line level between riaa preamp and main amp with single opamp buffer as per rod elliot guide. Setting for 3dB worked ,but i still was not completely happy.

I don't listen very loud on this setupr , but I do prefer a decent amount of bass.

In the end I added a simple bass boost of about 10db at 50hz with a single opamp between my riaa and main amplifier. I'll make it neat one day ,currently it just lives on a peace of vero board with seperate +- supply.

10db is unnecessarily much , but it does give it a lot of presence at low volume.

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I'm sure i'll have an itch to change something again. But I do prefer line level active filters compared to large caps and resistors and inductors at the driver.

Having an active filter is so much easier with a single full range driver.
 
I see you are playing from the turntable.... but if you were to digitize that, you know you could do all those little parts in the digital domain and tweak to your hearts content?

Getting your files on a computer, then adding all those active filters working in a piece of software like JRiver, you probably could achieve an even better sound.

Just another point of view I wanted to add....

I would love to build a WIBAQ lookalike one day...
 
I took my BetsyK drivers to Lorantz Audio here in Melbourne for the full series of tests and this little humble driver has a really good distortion profile above 100 Hz and a quite acceptable freq response - it's a rather good driver despite the relatively low cost - I'm crossing it over at 150Hz using a folded open baffle and driving it with either an optomised F5 amp or the Neurochrome Mod 86 amp - initial impressions are extremely open sound with no fatigue, well controlled transients, no overdamping and naturally, no box colouration - quite a 'secret charmer', this one.

This isn't a TABAQ design (actually a FAST) but I thought I'd mention such a positive result.
 
Hi tangmonster

I am really surprised that the bass is weak. Did you over stuffed it ? Try to remove some of the stuffing. The last one third og the line is unstuffed.

I am using 4" Tang Band in my original TABAQ and very seldom use the sub for music listening.

I have never heard these speaker units, but in general a single driver loudspeaker has a wide image.

Hi
Bjørn
 
Hi tangmonster

I am really surprised that the bass is weak. Did you over stuffed it ? Try to remove some of the stuffing. The last one third og the line is unstuffed.

I am using 4" Tang Band in my original TABAQ and very seldom use the sub for music listening.

I have never heard these speaker units, but in general a single driver loudspeaker has a wide image.

Hi
Bjørn

Did do a test and removed all stuffing which had little effect. Only stuffing top part as per dumbledog's posts.

I truly believe it is a situation of my personal taste though. and possibly combination of ultra linear valve amp and speaker?
The same amp had much more bass with standard 2 way bookshelves.

But my understanding is that the ultra linear setup should actually have more volume at the high impedance lower end than a solid state would?

BSC helped a bit , but still not to where I like it.

i'm still learning and experimenting.
 
So my understanding is that for a valve amp with lower daping factor and higher output impedance , where the speaker has higher impedance there will be higher output V and thus watt.

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I have not yet used a solid state amp on them , will try and test how it sounds.

Gastroschisis measurements on page 12 shows this:

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The 10dBV gain I have at 50hz makes up for the drop.

I am going to modify my circuit for 6dBV gain at 50hz and do some more tests. the current 10dBV gain is a bit Bassy , but nice to my bass freak ears :) especially for older pressings that is normally lower on bass.

With the current 10dBV gain at 50hz I have no need for any BSC or other circuits with these speakers and they sound VERY nice to me.

Very certain they are not connected out of phase. I swapped them to make sure at one stage. :) I have made that mistake many times in my life,son one of the first things I try :)
 
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