Dynaco A25 sound quality

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Sealed and braced. Should be better at the low end yes? I never thought my A25s were particularly impressive on the bottom, compared to AR 4x for instance.

Haha! Choices are good: I always liked the A25 for the bass as compared to my friend's AR 4ax.

In high school band (1971-1973) we auditioned the A25 and we thought it sounded pretty good. The main listening system in the band room were Wharfdales with sand-filled cabinets, driven by Dynaco PAS 3 and ST70. The turntable was an Empire, as I recall, outfitted with the Shure tonearm. Can't remember the cartridge, though.
 
frugal-phile™
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...the inductance of the A35 coil...

The A35s i have dissasembled do not have an inductor.

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dave
 
Very flat drivers with good rolloff tend to high voicecoil inductance here about 3mH if you guesstimate. It's almost like they come with a bass or bafflestep coil built in:
H1411-08 A26RE4.

I usually look at 10kHz impedance. 35 ohms is highish. You will find the inductance fights the filter a lot. You won't get away with a coil and a cap with these babies.

Usually a coil and a bit of impedance correction is better:

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Often throw in a notch filter too for breakup. Of course, the Dynaco style uses no filter at all. Doesn't mean you can't though.

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That bass filter doesn't actually do much. :)
 
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Just built a version of this, but with Seas 27TFFFC instead of the original H087 tweeter. Filter is 4.7 uF and 2.2 ohm. I have never heard the original Dynaco 25, but I am stunned by the sound they make with the 27TFFC tweeter.

It is detailed, and at the same time exremely relaxed. It can play loud without being tiring. When pushed very hard on some music you can hear the tweeter struggling a bit, but this is at sound levels much higher than I ever normally listen to.

It is strange to me that a 10" bass/midrange can provide so good midrange! Both male and female voices just sounds magical. I wonder if this is because the lack of filter on the woofer, or is it just an exeptional good driver? It is hard to be believe it was produced in 1971. Bass is not very deep but fast and always present, without being too much.

Have anyone compared the A25 to the new version from seas A26?
I have read that some people just think the A26 is a marketing gimmic from seas just for profit.. I need to the hear the A26 first but I find it hard to believe

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Ive owned the Dynaco A25 recapped and the tweeter upgraded to the Seas 27TFFFC. I thought the biggest drawbacks were lack of dynamics and definite lack of midrange clarity/resolution. I also own the Seas A26: much better in every way then my "upgraded" A25. Not in the same league at all. I sold my Harbeth shl5plus with not too much regret after comparing with the Seas A26
 
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Ive owned the Dynaco A25 recapped and the tweeter upgraded to the Seas 27TFFFC. I thought the biggest drawbacks were lack of dynamics and definite lack of midrange clarity/resolution. I also own the Seas A26: much better in every way then my "upgraded" A25. Not in the same league at all. I sold my Harbeth shl5plus with not too much regret after comparing with the Seas A26

Was it better with the 27TFFC, or was it worse?
 
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