DIY Audio General - stuff you're making, tips, advice sought, etc

I have some nails and planks, so I can even provide the parts :+1:

1 Like

Can you recommend a sub to cover 200 Hz & below? (for the baffles) :smiley:

Still struggling to get my head round how tasteless the Club 27 idea is, I’ve no doubt the products are fun, but…

45", they don’t go very low, they will probably benefit by being nearer to some corners. Still enjoying them.

1 Like

Yes quite morbid really, Dutch humour?

I recall that there was some ahem ‘surprise’ when they launched this product range a few years ago but I’d actually forgotten about it until now.

Where is the x-over happening on these? ~ 1Khz?

Not sure where the X-over is. They call the 12" unit a wideband driver, I think I have seen it mentioned as going to 2K. I will fire them over a question on it as I would like to know too.

Yep they will need 100 hrs before you hear them at their best.

Here are my Kurt’s

9 Likes

Very Nice, have you painted/coated the cabinets? I think I will probably veneer mine at some point.

What’s the tweeter capacitor value?

1.5uF

If that’s the only component, i.e it’s a first oder, 6dB per octave xover then assuming the tweeter is a nominal 8ohm load then that’s a crossover point of 13kHz.

Des in Sheffield built them for me and painted them the same colour as our room followed by several layers of mat varnish to protect them.
I think crossover point is relatively high as they are a full range driver.
Des could tell you more he has built a few of the Bastanis kits and at prestige is working on some jimi’s.

1 Like

Right, so here is what I have been faffing around with.

Basically, it is what a World Designs LCR phono stage could be if it went with the PSU3/Pre3, using standard valves. The inductors are from Sowter, the bit at the front is an inverse RIAA network to check the response and isn’t in the final circuit (obviously).

Results? Seems very good so far in most ways, I’ve tried it out by ear mostly and it seems that the equalisation is pretty accurate. I’ve used ClarityCaps in the EQ network and Kiwame resistors, and the inductors are obviously pretty accurately made (I had taps put in either side to adjust if necessary but so far it hasn’t been.

There is only one parameter where the Phono3 is obviously better, and it is still output level. And I have no idea why.

The sim says that 5mV in at 1kHz should give about 1.6V out, and as made it really doesn’t. Given my test equipment is a multimeter and a Hantex USB scope it is difficult to dig in with any accuracy, but it is fairly clear that it isn’t. The same sort of level from the CD player at 9 o’clock on the volume control needs around 1 o’clock from this. Hmm (but not hum which shows that the power supply is OK given that there is no PSRR from a cascode).

1 Like

There is an 8.2 Ohm resistor in series with the cap but I guess that just reduces level. I guess that is why they call the 12" unit a wideband driver if it is going up to 13K.

1 Like

They look very good. I am toying with spraying mine but as I said my first cabinet is a bit messy so was thinking veneer might be easier (or maybe not!). Anyway we are trying to move house so projects will need to take a back seat for a while.

What is the thinking behind that configuration of input as opposed to the more typical Shishido type circuit?

I realise you are using a higher impedance network.

From @coco’s way of doing things, impedance matching the network from the output impedance of the first stage rather than a resistor afterwards. It is supposed to give a bit more gain out of the first stage.:thinking:

1 Like

Just need to put it in a case now :slight_smile:

4 Likes

TV off centre fail :wink: