OB Experiments

[Ali Tait]

Have recently lashed up a pair of Altec Lansing 806-8a's with Isophon tweeters. Sounding pretty good so far-

http://i1286.photobucket.com/albums/a616/aliballybee1/4D46B9D1-7877-47E3-88FC-ACDB72D3324D_zpsxvsk0nii.jpg (http://s1286.photobucket.com/user/aliballybee1/media/4D46B9D1-7877-47E3-88FC-ACDB72D3324D_zpsxvsk0nii.jpg.html)

Great match with the OTL, being around 104db!

[nthall]

Cool. Is that one of the Transcendent amps? They're made in my neck of the woods. I've been wanting to try one out.

[walpurgis]

Those Isophons look familiar Ali. :)

Nice aren't they?

[Ali Tait]

Cool. Is that one of the Transcendent amps? They're made in my neck of the woods. I've been wanting to try one out.

Tis indeed, the Mini Beast. Very good amp indeed, if 4w is enough for your speakers. I run an active system, with the OTL only used from 700hz, so has an easy life, especially with the Altecs being around 104db or so..

[Ali Tait]

Those Isophons look familiar Ali. :)

Nice aren't they?

They are indeed Geoff. Thought it was about time I gave them an airing. :-)

[nthall]

I think 4 watts would be a little light for my setup. I've been reading up on The Son Of Beast. We live in the same town, but I've never met him. I've read his books. I'm surprised we've never crossed paths.

[Ali Tait]

Yes, some very sensitive speakers required. Very good amp IMO though, only recently built it.

[nthall]

My speakers are 98db, but they seem to like a little more power. I like it loud too.

His designs look solid. The Beast looks awesome but I'd probably need a commercial air-conditioner with two of those running.

[Ali Tait]

Yes, they do have the tendency to act as a room heater too. Not quite such an issue over here though, with our crappy weather. :-)

[Firebottle]

I've been reading up on The Son Of Beast.

I built his original 25W OTL many years ago and used it for serious listening for many years. Very good sound but unfortunately the custom mains transformer failed a while ago.
I have bought a couple of replacement transformers and am going to re-build it along the lines of the Son of Beast, but with a few of my own tweaks.

I like OTLs, I only have three :thumbsup:

[Sovereign]

Enjoy the journey Ali.

[Qwin]

OTL ?

[struth]

Outlaw maybe?

[Ali Tait]

OTL ?

Output Transfomerless valve amp, in this case a Transcendent Sound Mini Beast Ken.

[Ali Tait]

Enjoy the journey Ali.

Thanks mate, these are sounding good. I'm running them 700hz-7k, which seems about right looking at the frequency response.

[Jimbo]

Looking good Ali, I like OTLs. Transparent and clean sounding amps. I see you tweeters have got bigger ooo errr.:)

[nthall]

I have never had one.

[Macca]

Alan Firebottle brought one of his OTL jobs round to my place - it was very good, so good that when he left and I put my XTZ amp back in the system just sounded broken. Took me a week to re-acclimatise.

[Sherwood]

Have recently lashed up a pair of Altec Lansing 806-8a's with Isophon tweeters. Sounding pretty good so far-

http://i1286.photobucket.com/albums/a616/aliballybee1/4D46B9D1-7877-47E3-88FC-ACDB72D3324D_zpsxvsk0nii.jpg (http://s1286.photobucket.com/user/aliballybee1/media/4D46B9D1-7877-47E3-88FC-ACDB72D3324D_zpsxvsk0nii.jpg.html)

Great match with the OTL, being around 104db!

Straighten up your vinyl man!! Are you living on a hill? :)

[nthall]

Yes, they do have the tendency to act as a room heater too. Not quite such an issue over here though, with our crappy weather. :-)
We have crappy winters, but the summers are crappy too. Ours can drop below -20 in the winter, and go above 40 in the summer. We get all 4 seasons.

[Firebottle]

OTL ?

The one Ali has does have blocking capacitors on the output though.
I have heard a Polish copy of this OTL and it was exceedingly good.

[nthall]

The one Ali has does have blocking capacitors on the output though.
I have heard a Polish copy of this OTL and it was exceedingly good.
Have you ever tried building one with any other type of sweep tube? I have boxes full of them. I got most of my tubes from buying up the hoardes of retired repairmen.

[Ali Tait]

Straighten up your vinyl man!! Are you living on a hill? :)

LOL, pic was taken during a heavy listening session. It's all tidy now.

[Clive]

The one Ali has does have blocking capacitors on the output though.
I have heard a Polish copy of this OTL and it was exceedingly good.
I've been tempted for a while...the 300B from Bruce would be nice but eight 300Bs ain't cheap. That leaves Mini Beast or Evermore (16 x EL34 or 6550).

[Ali Tait]

Mini Beast should be good on you speakers Clive, you run actively do you not?

[Clive]

Mini Beast should be good on you speakers Clive, you run actively do you not?

I do indeed, the OTL would handle 90Hz upwards. The MB seems like the sane option. The speakers being 16R should help too.

[Sovereign]

Brilliant, glad you are finding your way with them .
I was a bit sad to see them go to be honest but I'm certainly not in the place to make any use of them and I know that you are so have a blast with them .

[Ali Tait]

Thanks mate, much appreciated.

Hope your health is picking up?

[Ali Tait]

Further experimentation. Now using a rare pair of Crysler D 500 compression drivers with horns along with a pair of SB Acoustics Sartori TW29r tweeters. This is the best I've heard so far, though after talking to a friend who is building his own horn setup, I'm going to have to bite the bullet and go four way, I'll use a pair of Alpair A12P drivers 200-800hz, as the Eminences are not really happy going up that high.

http://i1286.photobucket.com/albums/a616/aliballybee1/Mobile%20Uploads/E4F67504-34C6-47E5-84F2-CE02EB4BB39F_zpsyx5heoew.jpg (http://s1286.photobucket.com/user/aliballybee1/media/Mobile%20Uploads/E4F67504-34C6-47E5-84F2-CE02EB4BB39F_zpsyx5heoew.jpg.html)

[walpurgis]

Wondered when you'd get around to using those Ali. :)

[Ali Tait]

They are better than the Altecs, in this application at least. From what I've found online, they were made to compete with the Altec speakers back in the day.

Very good drivers, as are the tweeters.