Tweeter Amp for OB or Horns

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izzy wizzy
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#136 Re: Tweeter Amp for OB or Horns

Post by izzy wizzy »

[quote=IslandPink post_id=164795 time=1552336212 user_id=13
1. Which bit ? ie. which bit should I change that wouldn't upset the accuracy of the 4uF case ?
2. Who said I had some 6AX4's in the sim ? :D I just put a solid-state bridge in there and checked the 6AX4 dataheet yesterday.

Ooh, did you just change your comment - it changed in my reply to you - spooky !
[/quote]

Yes I changed it coz sounded snotty when read back and not wot I meant to say.

I've found in the past that the more accurate the data you shove in including the diodes the better the result for differing values of caps etc.

Still annoying when it don't turn out right.

I'll go back to Gil Evans.

Cheers,
Stephen
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IslandPink
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#137 Re: Tweeter Amp for OB or Horns

Post by IslandPink »

OK that's a blameless activity - just lining up my listening, listening to the left channel, sounds like it's doing some good things, right channel feeding a 10R resistor, we will get to him in due course. This is through a lash-up with the 288/Yuichi with 10R attenuation , and G3 ribbon with 2.7R unused Mundorf Zn cap inline. On the 'Head-hunters' mounting ( DtB knows what I mean )
Plenty of stuff to run-in, including Bud's transformers.

Here 's the datasheet -
https://www.hammfg.com/files/parts/pdf/1182E240.pdf
and I checked the Tx secondary with multimeter, reads 68R.

Might get a bigger cap for the HP so I can hear more during evaluation , this sounds nice. Currently got 0.0047u/150k in there.
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IslandPink
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#138 Re: Tweeter Amp for OB or Horns

Post by IslandPink »

Warming up with Michael Hedges -
Tweeter_amp_playing.JPG
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#139 Re: Tweeter Amp for OB or Horns

Post by IslandPink »

OK it's not often that laugh when listening to a system, but I just put on Sabicas' 1958 record 'Gypsy Flamenco' and had to swap channels in order to hear his guitar and the castanets. The castanets are ridiculously good. I'm going to have to go back and listen to that track again in a few minutes.
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izzy wizzy
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#140 Re: Tweeter Amp for OB or Horns

Post by izzy wizzy »

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IslandPink
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#141 Re: Tweeter Amp for OB or Horns

Post by IslandPink »

This is definitely the least broken thing I've ever heard - but I've not heard an OTL through a compression driver and ribbon tweeters.
Playing 'Mystery R.P.S. No.8' from 'Full Circle', the cymbals and other high percussion sounds are delicious.
Will try & get a some 0.01u caps in there in next day or two, so it's just the output transformers limiting the HP filtering.
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#142 Re: Tweeter Amp for OB or Horns

Post by IslandPink »

I think I'd give OTL the edge on strings, from memory. Got an old Marble Arch reissue of Adrian Boult Holst Planets on, 'Venus' is beautiful, though !
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IslandPink
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#143 Re: Tweeter Amp for OB or Horns

Post by IslandPink »

A bit of final tidying-up here today.
I have replaced the Russian pio cap for one pentode G2 with the same Mundorf ( white EVO ) cap as the other channel. That was a bit fiddly.
Also did some mods so that my knob is now going out straight, not going off sideways.
This involved filing some small holes in the Teflon journal from circular into ovals using a very small file.
There was hardly any puncturing of the left hand third finger experienced during this work .
Tweeter_Amp_finalUnder.JPG
This amp is now 'Owston-ready', like an Owston-ready chicken !
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Ali Tait
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#144 Re: Tweeter Amp for OB or Horns

Post by Ali Tait »

You don’t want your knob coming out sideways.. :D
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#145 Re: Tweeter Amp for OB or Horns

Post by Cressy Snr »

Ali Tait wrote: Fri May 03, 2019 6:38 pm You don’t want your knob coming out sideways.. :D
Oooh no missus, no.....no, yes, no...don’t titter....listEN..... no... :lol:
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Dave the bass
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#146 Re: Tweeter Amp for OB or Horns

Post by Dave the bass »

S'been awhile...

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#147 Re: Tweeter Amp for OB or Horns

Post by IslandPink »

Ali Tait wrote: Fri May 03, 2019 6:38 pm You don’t want your knob coming out sideways.. :D
It was also quite stiff, but I solved that problem in the process of straightening it up.
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Toppsy
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#148 Re: Tweeter Amp for OB or Horns

Post by Toppsy »

IslandPink wrote: Fri May 03, 2019 8:40 pm
Ali Tait wrote: Fri May 03, 2019 6:38 pm You don’t want your knob coming out sideways.. :D
It was also quite stiff, but I solved that problem in the process of straightening it up.
Mark,
really what on earth were you thinking about having a stiff knob in the first place?
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#149 Re: Tweeter Amp for OB or Horns

Post by IslandPink »

I'm out of my depth now, I really have no answer to that one :!:
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#150 Re: Tweeter Amp for OB or Horns

Post by simon »

It's like the 1970s all over again!
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