Amplifier Experts?

[Bruce M]

A bit off piste but I volunteered to fix this on Sunday and had it stripped down in no time.

I found it interesting that it was designed to be serviceable! The ribbon cables attach to a locking socket rather than direct solder. A new drive belt & set of capacitors should have it back to good.

[neilbardsley]

Anyone bought expensive HiFi cables recently ?

MONSTER CABLE V A COAT HANGER

https://gizmodo.com/audiophile-deathmat ... ger-363154

Very interesting. I've sorted my problem. The bridges between the pre amp and main amp had been dirty/attached/something. I tried cables and all worked well then I cleaned the bridges (which are thicker coat handers) and put them back in.

Listened to Yo Yo Ma playing Bach 6 Cello suite. It's one of those universal albums that transcends genre.

https://www.youtube.com/watch?v=YnUVrMgsRFA

I've loved it since I heard it performed at the Wigmore Hall 20 years ago? (unfortunately not Yo Yo)

[gridgway]

Well I have success! My amp works (first time!)and makes a very nice noise. It's very round and bassy and I really like it. I may have made a bit of a cockup though with the heat! I made my own case rather than buying the case that was available with the kit. I just guessed the size. As you can see from the pic, it all looks ok. But being class A it kicks out a huge amount of heat and my heatsinks are smaller than those in the official kit. I've only used it for short periods and it gets proper hot. A max of about 50 degrees is recommended, but I think I am going above that. I've got an IR temp gun coming to be sure. I've got about 2/3rds the area of the ones in the standard kit which are the same height, but 8" long not 6".

Unfortunately it means a lot of rework, but hey ho!

You can also see "chinese box amp", the Class D cheapo kit in the background with the original early 2000s Slimp3 streamer as well.

IMG_20190205_212729 by graham Ridgway, on Flickr

[911MRP]

Great to see people still making such stuff Graham. Making me nostiagic -- back to growing up!

Use it to also boil water to make a cup of tea then kick back enjoy your handiwork and a nice brew

Cheers

Steve

[gridgway]

Ah that's the answer. Water cooling, use it to supplement the central heating boiler!

[911MRP]

Maybe but wouldn't shout about water-cooling on ddk

[impmad2000]

The heat sinks work a lot better if oriented with the fins vertical. Might help a little.

[gridgway]

Ah yes, that's a good idea Tim! I'm expecting to get new ones I'll look for vertical fins.

[neilbardsley]

I'm dim where are the heat sinks in the photo?

[hot66]

outside edges of the case

[gridgway]

Here you can see them better before it was built up. The heatsinks form the sides. I've got bigger heatsinks coming with vertical fins. Means I'll have to remake the top and bottom as well, but hey ho.

Then I can start on the speakers!

IMG_20190101_151705 by graham Ridgway, on Flickr

[neilbardsley]

Now the amp/received in the other house has stopping working. I'm not sure I'm going to open that one up because it's always been a bit rubbish and probably better to start again.

I must admit that Ashley has got me thinking about the CD v Vinyl debate again. I've been listening to more CD because I can't quite similar to get the vinyl's clean enough for a good noise. Anyway last night I was went to a performance of Cosi Fan Tutte in Goodenough House in London http://www.goodenough.ac.uk/about-us/ne ... -fan-tutte. Mostly done by students but still a good production. I do wish the Opera was just a bit shorter. I struggle to sit still for the last 90 mins and I wasn't the only one. Back to point. I've bought a CD and Vinyl recording (unfortunately I couldn't get the same recording) but will report back on which I prefer.

[Ashley James]

With Classical music, opera especially, record players are absolutely dreadful. They mistrack on the vocals, congest on complex orchestral passages and deteriorate toward the end/Centre.

I sold my Thorens in 1987 and we stopped making CD players in 2006. Since then I’ve imported all my CDs, used Apple Match and bought downloads.

I just select the track I want on my phone and tell my ATV or Airport Express to play it to my active speakers.

No clutter and absolute clarity and naturalness. Or I use HD800s.

[gridgway]

But they do Jimi Hendrix extremely well!

Peter Gabriel tells that his album "So" had to have the track order changed to move the final track "In Your Eyes" as it had too much bass for the end of the album (near the middle).

As an aside, just been reading about re-issues of albums on 45rpm. That's strange!

Graham

[gridgway]

Just done a temperature test of my amp. The power transistors got to about 56 degrees c after 15 mins so that won't work. Will have to rebuild with bigger heatsinks

Graham