Show Us Your Speakers!

[YNWaN]

Thanks Grant - there are some more details here http://www.homebuilthifi.com/project/8326.

[struth]

like the rings.. reverse fitting, so sit flush.

[YNWaN]

Hmm. I assume Mark, that you are saying the Daytons are fed directly from the same filter section that the Yamaha tweeters are on?

If so, then the Daytons will be outputting across the same treble range, at least until the Yamaha tweeter rolls off, probably in the upper twenties of KHz. This also lowers the HF impedance to a nominal 4 ohms and that would alter the treble curve, giving the whole top end an inaccurate response.

If it was me, I'd definitely run the Daytons on their own parallel filter. A single cap in series with the supertweeter should do the job, providing a 6db/oct introduction at whatever chosen frequency. I'd aim at above 18kHz. This can be fed from the rear speaker terminals without needing to access the crossover. Output from the Dayton should not be significantly audible. If it is, then the filter is coming in too low.

Well there is a series cap to the super-tweeters - it’s 1.5uF. However, as it is then in series with one at 2.7uF it may be that the 1.5 should be increased to 3.5uF. Il give it a try.

[Pharos]

I agree with Geoff about the Xover.

[YNWaN]

Well I do too, but in my case it’s more easily said than done.

[Marco]

Posted on behalf of Pharos (Dennis):



Marco.

[walpurgis]

Ah. ESS Heil AMT1. Is that a replacement bass driver?

I heard those and the AMT1 Tower a couple of times many years ago and was mightily impressed. The AMT1 Tower has been on my 'list' for years. The top end and mid was superb and the bass depth and quality from the ten inch driver in the transmission line was phenomenal.

[Pharos]

Many thanks Marco.

They are a result of buying a pair of ESS AMT 1Bs from an ad. in Hi-Fi News in '02, rebuilding with new better ESS components in and upgrade to AMT1E, and then realising after a few years of bliss that the frequency response was 'smiley', and that sadly they failed on the grounds of 'monitor accuracy'.

The last iteration was one of three attempts using the Rogers LS 5/8 mid/woofer, which is a better unit, the last Xover made from a calculation based on the BBC report, but it turned out that the original mid/woofer was very different from the later production models, and so there is some error in this also. You can see the remnants of the original black felt gasket, for rear mounting, around the front of the basket rim.

But for the costs, even though the drivers are 44 and 34 year old technology, this is a very fine speaker for £1.5k, even in comparison with my newly acquired ADAM Betas listed at £28k. No expense spared in the work; 53 wood braces in each cab, tweeter pots 25W jobs, total attenuation of 10 dB in about 0.3dB steps, the switch gives 5dB and the pot 5dB.
The plinth was increased from 3" to 7" to get the tweeter height right and increase the internal volume from about 70lt to 81lt. All panels extensively damped, mid absorber all around the inside, rewired with 3.8mm c.s.a. wire.
The mid/woofer frame was extensively damped, and good terminals put on the basket. A lovely air path is provided downwards to the bottom and back up to the ABR which is rear mounted, and the black parts are a veneer of 1mm EPDM rubber for damping and durability. The granite plinths did really improve impact and bass definition.

For me the comparison between these and the Betas is very interesting, Klaus Heinz of ADAM talked extensively with Oskar Heil prior to developing his version of the AMTs, so these two represent and compare the initial development by Oscar Heil, Nelson Pass, and Von Scweikhert in the early 70s, with that in the Tensor series in 2009.

[Blueflash]

This is my view from my ear standpoint

[Pharos]

I assume the 50s are passive judging by the cables and that silver box at the bottom.

I'm sticking with my SCA2 as permanently as I can predict, but the remote - trying to read the white print on silver in low light!