Transcendent Sound Pinnacle 300b OTL Monoblock Amplifiers

[Ali Tait]

Had this kit for quite a while, just not had the time up to now to get this done. Have finally made a start though.

I'm building these with a few mods, first of which are some very high quality regulated filament supplies- one for each 300b so eight in total, four in each monoblock. These are not part of the standard kit so I need to find room for them.

I've heard a similarly modified pair at a previous Owston which was easily the best amp I've heard so far, so if this kit gets anywhere near that I'll be a happy chappie.

First job is the filament supplies, got all the components laid out-

https://i.imgur.com/nRdWj6Sh.jpg

Getting there-

https://i.imgur.com/ABIkSaLh.jpg

All done-

https://i.imgur.com/022DjN5h.jpg

Made a start on populating the chassis with tag strips etc-

https://i.imgur.com/1WM7AANh.jpg

That's as far as I've got for now, will update the thread as I progress.

[Firebottle]

That's a lot of filaments Ali, looking forward to the next instalments.

[Ali Tait]

It is, now just got to find room for them in the chassis lol.

[jollyfix]

Looking good Ali.

[AD Audio]

Hi Ali
Have a look at my Website for a pair I built recently. https://adaudioconsultants.wordpress.com

David

Sent from my ONEPLUS A5000 using Tapatalk

[Ali Tait]

Cheers, will do.

[Ali Tait]

Noted about switch on surge, am going to fit a delay board for the HT.

[Shadow Moses]

I have the Transcendent Sound Phono stage, love it.
The dynamics are shocking at times

[Ali Tait]

Yes good kit, currently use a Mini Beast.

[Ali Tait]

Looking good Ali.

Cheers Dave, will get there eventually lol.

[Pepperamip]

This looks like it will be a serious piece of kit once it's complete. Are you going to love the mini beast on?

Sent from my CLT-L09 using Tapatalk

[Ali Tait]

Yes will be once this is complete and I’m happy with it. You want first dibs?

[Pepperamip]

Would love to Ali but id have to sell a couple of bits to make the grade. I reckon it would suit my 95db klipsch perfectly

Sent from my CLT-L09 using Tapatalk

[Ali Tait]

Yes it would, certainly sounds great on my Impulse H2’s.

[Pepperamip]

Any more pics to tempt us Ali. It must be nearly built now surely ;)

Sent from my CLT-L09 using Tapatalk

[Ali Tait]

LOL did a little bit yesterday evening. Have HT delay boards to pick up tomorrow from the PO, have ordered the transformers from Amethyst, two week lead time on them though. Finished my current project Friday past, have some time on my hands so should make some good progress this coming week.

[Pepperamip]

Good stuff I find these build fascinating. Should try one myself at some point.

Found a great interview with Bruce Rozen lit of TS which is well worth a read if you haven't already:

http://www.audiodesignguide.com/otl/interv.html

Sent from my CLT-L09 using Tapatalk

[Ali Tait]

A bit more progress. Fitted the HT delay board from K&K Audio- this is not part of the supplied kit, but it will give the 300b's an easier life- eight 300b's are not cheap!

https://i.imgur.com/ihxd8ar.jpg

Board built up-

https://i.imgur.com/HmvwnLF.jpg

Installed into chassis-

https://i.imgur.com/EVmX43H.jpg


Heater wiring to the front end valves - these will be supplied from a winding on the toroids I'm having made-

https://i.imgur.com/o7zcaAx.jpg

More progress-

https://i.imgur.com/SfRCbtV.jpg

Getting there with the front end-

https://i.imgur.com/bwqrnoM.jpg

[vinylspinner]

Looking good Ali, will she be at Owston?

Nigel

[Ali Tait]

Should be, as long as everything turns up in time!

[smangus]

Great thread , love it. The build looks really good too! :)

[Firebottle]

I would have kept the twist on the front end heater wires Ali. Keep the twist as close to the bases as practical.
Looking good.

[Ali Tait]

Yeah thought about that, but that’s the way it’s done in the destructions which I’ve followed as he’s stingy with the wire, looks like I’m going to run out as it is lol.

[Gazjam]

Looking great Ali,

Be a treat to hear ‘em at Owsters mate.
Taking my PS Audio BHK Signature pre...should be a good pairing.
My 300b power amp of Nicks is a superb match with it.

Good call on the soft start circuit, want to get as much time out your 300Bs...pricey as you say.

[AD Audio]

I would have kept the twist on the front end heater wires Ali. Keep the twist as close to the bases as practical.
Looking good.Alan, Bruce's instructions state to wire as Ali did and despite my scepticism the one I built had no audible hum. As Ali says Bruce is very stingy with the wire and also with diodes (mine came without)[emoji3]

Sent from my ONEPLUS A5000 using Tapatalk

[Ali Tait]

Great thread , love it. The build looks really good too! :)

Cheers Andy, been a lot of work but I enjoy doing it.

[Ali Tait]

Looking great Ali,

Be a treat to hear ‘em at Owsters mate.
Taking my PS Audio BHK Signature pre...should be a good pairing.
My 300b power amp of Nicks is a superb match with it.

Good call on the soft start circuit, want to get as much time out your 300Bs...pricey as you say.

Aye be good mate, like to compare these to your amp. :-)

[Ali Tait]

Pretty much done now, or at least as far as I can go until I get the toroids Amethyst are making for me, then it's just a case of wiring up the filament supplies and Bob's yer mother's brother. Four filament supplies added, again not part of the original kit but these will make a significant improvement-


https://i.imgur.com/lb2hp10.jpg?1


https://i.imgur.com/BoEQX8g.jpg?1

[Gazjam]

Are those Andrew L’s filament supplies...topology looks familiar?
If so, better than anything commercial and should be great!

[Ali Tait]

They are indeed, wanted the best available. :-)

[Pepperamip]

Can you listen to them yet Ali or do you have to wait for the arrival of the Toroids?

They certainly look the part!

Sent from my CLT-L09 using Tapatalk

[Ali Tait]

Can’t listen until the toroids turn up unfortunately- they will run the valve filaments.