FS: Type 26 DHT pre-amp.

[awkwardbydesign]

In the spirit of simplifying my system, and following the sale of excess cables, I am selling my type 26 pre. Based on Ale Moglia's designs, with help from Simon Shilton and diyAudio, it sounds fantastic, but is too complicated to be left for my wife to deal with. So while I am still able to, I wish to find a new home for it. It cost more than £1000 in parts, plus all the work involved, so the asking price reflects this.
It comes with several spare valves, and the separate psu. Many more pictures and details will be posted, but that will take some time to organise. The veneer is Cherry, and the top plate is 5mm aircraft grade aluminium alloy.
To be honest, I never thought I would sell this, and still wouldn't if there was anywhere I could use it. There isn't room in the loft system, so it will have to go.

I am in Plymouth, and these are to heavy and delicate to post, so will need to be collected. Alternatively I can deliver them within a "reasonable" distance, for the cost of the diesel.

I am asking £1000, but may consider sensible offers if they don't sell quickly.

https://live.staticflickr.com/65535/51872388005_321676aa5a_c.jpg https://live.staticflickr.com/65535/51871741661_f233818d16_c.jpg
https://live.staticflickr.com/65535/51872387825_d33bc1530e_c.jpg https://live.staticflickr.com/65535/51872057494_5e64d74d5a_c.jpg

Power supply.
https://live.staticflickr.com/65535/51870776612_97eb9039a0_c.jpg https://live.staticflickr.com/65535/51871742161_917f5def72_c.jpg

Umbilical cable.
https://live.staticflickr.com/65535/51871741921_e9594b9122.jpg

Carrying box (one for each chassis, including lids, but not the cat.)
https://live.staticflickr.com/65535/51872057424_0ea2beb87d_c.jpg

I documented the build on HiFi Wigwam (as it was once called!). https://www.hifiwigwam.com/forum/threads/type-26-dht-pre-amp.72468/
Many of the pictures have gone, as I started on Photobucket and then moved to Flickr. I may be able to recover some of them if needed.
Also the diyAudio thread has many of my questions (and their answers). I had to read hundreds of posts before I even started; without the help I received I couldn't have attempted this build. I now know how much I don't know!
https://www.diyaudio.com/community/threads/26-pre-amp.151421/

Feel free to ask anything.

[philv]

Very nice.
What are the 4 knobs on the front for?
Nice look to tnem.

[Lawrence001]

I was wondering that, from the internals the one in the bottom middle seems to be the source selector while the two outer ones look like stepped attenuators but with not many steps. Now if the mysterious top middle one was main volume while the L/R were fine tuning/balance that would be a very useful feature indeed.

[fafarskid]

I like that cat.

[Old boy]

Has this been sold ?

[awkwardbydesign]

I will be adding updates, including frequency response, circuit design and components used as I find all my notes. The top knob is indeed the volume control, a TKD 2CP-2511 (Stereo). Expensive, but worth it IMO.
The two extra knobs are for the balance controls I added. IIRC, they are up to 6dBu cut each side. I will add that info too. My room has an annoying imbalance, no matter what speakers I use, so I added these.
It has not been sold yet, nor the cat.

https://live.staticflickr.com/65535/51793983078_096424ac69_w.jpg

[bumpy]

I have a few general questions if you don't mind

1. What are the attributes of the Type 26 valve - its not known to me?
2. Is the amp dead quiet into sensitive speakers 95dB+
3. Is the amp free of mechanical noise such as transformer hum.
4. How hot does it run
5. How many pre-outs does it have
6. Can you put its sonic quality in context against other pre amps.
7. Which other valves are used in the two boxes?

Thanks Chris

[Resonator]

PM sent

[awkwardbydesign]

Chris;
1) See Ale's site for more info.
2) Don't know. But it's fine with my 92dB Tannoy MG12s.
3) Yes, at least to my old ears!
4) Cool. You can put your hands on the valves.
5) 1 pair normally, but the spare pair of inputs can be wired as outputs. I did that when I tried a pair of subwoofers.
6) See 1) or the diyAudio thread.
7) AZ1 meshplate rectifier, and the two #26s. No others.

Richard.

[awkwardbydesign]

As the question has been asked, I would only ship these on a pallet, paid for by the buyer, and responsibility accepted by same. And that would cost well over £100 with insurance.

[philv]

What are approx dimensions and weight?

[awkwardbydesign]

Just been sold! Should have asked for more! :lol:

[awkwardbydesign]

Just for fun, here are a couple of pics of my 01A DHT pre. Same PSU, just a lower voltage, but the pre has gyrators not transformers on the outputs. And prettier veneer.

https://live.staticflickr.com/65535/51879259459_970d8dc59c_c.jpg

https://live.staticflickr.com/65535/51879257364_d5c16347d0_c.jpg

They match my GL75. :kiss:
https://live.staticflickr.com/65535/50856058556_1b64dc186b_c.jpg

[fafarskid]

All very nice Richard.
If I had more space, I would buy pre from you.
Is there difference in sound between those pre-amps 01A DHT and 26 DHT?

[Lawrence001]

I think he's sold the one he wanted to and he's keeping the other one.

Just out of interest what's an output gyrator?

Sent from my BKL-L09 using Tapatalk

[awkwardbydesign]

I think he's sold the one he wanted to and he's keeping the other one.

Just out of interest what's an output gyrator?

Sent from my BKL-L09 using Tapatalk

https://www.bartola.co.uk/valves/dht-pre-amplifier/01a-preamp-gen2/

https://www.bartola.co.uk/valves/2016/01/23/gyrator-pcb-boards-arrived/

https://www.bartola.co.uk/valves/for-sale/gyrator-pcb/