Now for the picture quality, I'm sorry, no money to buy the last Leica M8

All the best,

Zang

I will built both versions as soon as I have parts. I'll post pictures of the finished stuff, and appreciation about sound.

All the best,

GregVDS

Where did you get this heat sink? It looks like it matches Digi's silkscreen exactly. I can't find one like that anywhere.

[Edited by tomb on 11-15-2006 at 08:18 PM.]

All the best,

H.B.

I suppressed all the regulation section with OPA551, and all the resistors and diods are backside placed:

All the best,

ps tonight, I will try the intersil buffer board.

Regards

and yes, Gewa, all the layout is myself (AMB is the genius behind the schematic). The board is a small 17 x 53mm. I like the idea to put half the components (small ones) backside, this helps a lot to achieve smaller design, it goes in the 3D, letting 4 'paths' to be interwoven.

all the best,

Here are some pics of the Intersil buffer board build and use:

From top, all stuffed with adaptators. I lost a board, for to solder the 8 connections, I put resistor legs in another dip8 adaptator, but achieve to even solder the legs in the dip8 adaptor . Well, ok, next:

backside, to show you the 8 connection legs I speak of. Here I decide to pick them in foam, so no problem of solder flowing .

And here finished and stuffed with stacked Intersil HA3-5002. Limiting resistors are 33.4ohms, allowing the stack to deliver 360mA. Is it enough?

And here inside the SOHA.

the sound is very very nice, 'fresh and fast' in comparison with the OPA2134, without lacking in the lowest octave. Ayo's voice is mellow and wonderful the slow reggae is very deep. Faithless's MAss Destruction is superb, really, I discovered some guitars I never heard, somewhere on the front scene, left. String pluckings on 'The Man comes around' of Jhonny Cash are very convincing and his voice is perfect. Emmylou Harris sings as she never before in my ears. Stereophonics's very noisy Superman is here dissecated and intelligible, the layered choirs makes you wanna sing and hop with. Oh well, a lot of very good things to re-listen to with this kind of Output buffer.

And just this one to let you see the working small Epsilon12 (I had a PITA moment realizing that Q5 should have been in the other direction ... Anyway, all went ok in the end (of the night)). I think this kind of thing is absolutely mandatory, for without connceting amp output, the epsilon gives a 11 secs delay (with 1Mohms resistor R11), but monitoring the SOHA, the delay before click-in is 29secs! So allow around 30 seconds before your Soha stabilizes its output!! But plug your headphone 30 seconds after turning on will not be very good for your intersil... Hence the Epsilon12.

I hope you enjoyed these.

Now this stack is hot to touch, the OPA627's also become hot, and the LM78 LM79 are a little bit frightening: I could only let my fingers on it for 1 sec... I hope the case will be heatsinking enough. Are these LM overheat protected?

All the very best, and thanks for the support. and now casing (when money allow nice FrontPanel Express order

GregVDS

1. So where is the sound quality now compared to Millett w/DB's?
2. Have you tried the BUF634 version, and how does it compare? (I think I know the answer to this one - the Intersil's are probably better.)
3. Are you still willing to sell your extras?
4. Think we could offer a Group Buy or something similar?

[Edited by tomb on 11-17-2006 at 09:25 AM.]

dBel84, I didn't measure that, but will try this evening, though my multimeter is not very good.

tomb, your first question is quite difficult to answer, for I have an advice, but I'm practically sure it renders nothing to nobody for it depends on the tube(s) used, the settings of the DB and stuff like that. For my very own case, with all the difference between the two, and taking this as just my memories, the MH with DB is a tad better, but only with NOS RCA 12FM6, with all other tubes I tried, the sound was not as good as the SOHA. So I'm quite confident there is another tube outhere for the Soha which will shine in it. Do not take my words for reality , it depends on so much factors that i prefer not to insist on this comparison (my... I already did).

I still didn't tried the buf634 version, and now lacks one DIP8 adaptor because of my first mistake, so it will again take some time.

I'm still willing to sell my surplus, but there are not so much, I think one board per person is the best way to maximize the number of people who want these. It would be 6 USD per buffer board, without the shipping costs. I have 3 intersils and 4 bufs to sell.

GroupBuy is something else, I'm still frightened at this.

All the very best

GregVDS

[Edited by vixr on 11-17-2006 at 11:17 AM.]

Greg - I think I sent you PM, but it's hard to tell. The messages aren't saved, and I was not working from a computer. I would like to purchase one each of your boards and sent a PM with Paypal address.

[Edited by tomb on 11-19-2006 at 07:21 AM.]

I received your pms, yours too Tomb!

I think this is the best system, pm me to book my surplus board, first pm arriving, first served, I will make a list of status for the order, I still have to look for the shipping cost to the states, it should not be that much.

Thanks for the interest!

dBel84, I measured the DC at boot, and yes, I confirm, I read a very small transient around 8 to 9 volts in the two signals. Maybe my multimeter is not fast enough to catch the 10 volt and show it, but if mine can say 9V, it surely is. Then the thing is very fastly dropping, to a mere 0.1mV after 30 seconds, just when the epsilon clicks on (with 1Mohms R11, I precise this for if you use lower values, you'll have shorter click-on time).

All the best,

I will come back to make a list of status for all the pm received and will answer you, but children and spouse are yelling at me for presence and attention .

GregVDS

Many thanks,

All the best,