9 pin sockets

[jlefevre1]

What size circle diameter sockets should I get for the Mark III and ST70 boards. AES has them in 13/16 , 3/4, and 25/32 diameter vareties. I just ordered my boards and was going to order the parts to stuff them and hit this snag.

[Ty_Bower]

All the chassis mounted tube sockets on the Mark III and Stereo 70 are octal sockets, not nine pin. I'm not sure about the ST70, but the Mark III has holes which are slightly smaller than your average eBay Chinese tube socket. You need to be careful when you order sockets, or they might not fit in the hole.

These sockets from Triode Electronics fit perfectly and seem to be of very good quality. The only downside is they cost a little more.
http://store.triodestore.com/77-mip-8.html

If you are talking about the nine pin sockets that actually mount on the circuit board (the ones for the small signal tubes), I'm not sure it matters exactly what size they are. They mount on the top side of the circuit board, and they don't need to fit through any holes in the chassis.

[jlefevre1]

It is the tube sockets on the board. The holes for the nine pin sockets on the board form a circle. It is the diameter of this circle that I need to know. The pins sticking out of the bottom of the solder tail sockets form a circle and there are three different diameters of these that are available from AES.

[mesherm]

What brand driver boards will you be using?

[Dynakitguy]

Hi,
You can use either the 25/32" or 13/16" dia. pin circle PC mount sockets on the original Dynaco boards. (and most new boards)

Actual drilled hole pattern is approxamately 0.785" diameter.

Socket pins will adjust to the above diameters easily...I would not select the 3/4" dia. sockets.

Kevin @ Dynakit

[Bob01605]

Kevin is correct - all 9 pin PCB mount sockets are basically the same and any minor differences can be dealt with with a minor bend of the pins. Any 3/4 inch diameter 9 pin PCB socket will work OK on a Dynaco PCB board which has a hole diameter just a hair over 3/4 inch.

Bob Latino

[jlefevre1]

Thanks. That is info I needed 0.785 is the match to 25/32. I am taking on a rather ambitious project. I am converting my home theater from a 120 wats per channel transistor to using tube amps for all power amps. I have a subwoofer with a dual 4 ohm voice coil. I am going to use a ST70 with one channel on each coil and the inputs bridged for that. I have a pair of Mark III that I will use for the front right and left speakers. I will use another ST70 for the right and left surround speakers. And for the center channel I am going to use a Heathkit W4-AM which is an UL mono block with 5881 outputs that I will use 7581's in. I will rebuild all the ST70 and Mark III amps with the new all triode boards for drivers and replace the can cap on the Mark III's withe the under chassis kits. Of course everything will get upgraded and tested. The Heath mono block uses 6SN7's for drivers and splitter so I am already at triode there. That should get me rid of the out of production 7199 problem and into all current available tubes. My front right and left speakers are LARGE folded bass horns with 12 inch drivers and a horn mid and horn HF driver. The subwoofer is a dual coil 150 watt car audio sub woofer in a very large enclosure tuned to a 3 DB rolloff at 18 HZ. The rear surrounds are full range JBL units mounted in the wall and I have yet to build the front center speaker system. It should rock on Dolby digital Surround 5.1. I can also shift the reciever to straight stereo with the subwoofer still enabled and the Mark III's on those two very efficient front horn systems should hold there own to any program.

[SDS-PAGE]

Why would 9 pin sockets go through holes on the ST-70 chassis? I thought the entire PCB was exposed on top. Am I missing something here?

I tried setting up a surround system with tube amps once, but I was utterly disappointed with the sound quality mostly due to the fact that all my tube amps were driven by a digital processor. I actually prefer the sound of my all-in-one Yamaha receiver for movies. It certainly saved a lot of space (and money) for sure. I leave my tube amps for listening to music in stereo.

[Ty_Bower]

The 9 pin sockets don't go through holes. I'm the one that assumed we must be trying to fit a socket through a hole, otherwise why would we be worried about what size socket was needed?

Jlefevre1 just wanted to know what size 9 pin socket was the best fit for the circuit boards. It's been pointed out that it really doesn't matter much, if at all. Whatever size socket he gets is going to have enough play in the metal bits for it to fit the holes on the PCB.