What are those decoupling caps?Thanks.
I spent a lot of time to think what the best way for the layout would be in my case, so that I get exact symetry when building the left and the right ch. and the shortest path.
I decided not to use any exotic parts. The power supply caps are Long life High temp. Low ESR United Chemi-Con(equivalent to Pana. FC type if not better). The decoupling cap is Siemens MKT type (4.7uF). The resistors, metal film 1% (I matched them to 0.1%).
The PS is not ready yet. Hoping for tomorrow.
Greg
I spent a lot of time to think what the best way for the layout would be in my case, so that I get exact symetry when building the left and the right ch. and the shortest path.
I decided not to use any exotic parts. The power supply caps are Long life High temp. Low ESR United Chemi-Con(equivalent to Pana. FC type if not better). The decoupling cap is Siemens MKT type (4.7uF). The resistors, metal film 1% (I matched them to 0.1%).
The PS is not ready yet. Hoping for tomorrow.
Greg
Attachments
Pedja,
Thanks for the tip. I have also some non-polar electrolytics (10.0uF), but I thought of trying the MKT first. Do you think the non-polar electrolitics would be better in general?
The big caps are LXY type. Compared them to the FC's and they have the same parameters but a bit longer life.
Thanks for the tip. I have also some non-polar electrolytics (10.0uF), but I thought of trying the MKT first. Do you think the non-polar electrolitics would be better in general?
The big caps are LXY type. Compared them to the FC's and they have the same parameters but a bit longer life.
Excellent job..........once youve fired up
could you report on noise levels ?
Is the shielded coax cable to stop noise ?
Ive made 4 iterations of gainclone 2 inverted
and 2 NI. All produce buzzes and the last
i could faintly hear a commercial radio station.
I didnt have a 220pf cap to put on the rca plugs
as suggested in a previous post to silence this hash.
It wont stop me from experimenting till I get something
that sounds as decent as others have reported.
could you report on noise levels ?
Is the shielded coax cable to stop noise ?
Ive made 4 iterations of gainclone 2 inverted
and 2 NI. All produce buzzes and the last
i could faintly hear a commercial radio station.
I didnt have a 220pf cap to put on the rca plugs
as suggested in a previous post to silence this hash.
It wont stop me from experimenting till I get something
that sounds as decent as others have reported.
Hi Greg,GregGC said:
Generally not unless they are Black Gate NX. I use them for some time now and my findings are positive. But in my opinion it is not any hard to find better caps than those Siemens, I guess any MKP will perform better (there are many low priced good MKPs nowadays). Anyway, I think you can easily swap the caps in your amp and check what is it you like.
Pedja
Pedja, thanks. I'll try the MKP's.
Sandro, thanks. The coaxial is to decrease outpu/input coupling within the box because the lenght of the wires happpened to be kind of long. As far as RF, the housing is connected (should be) to Star-GND, so the whole assembly is shielded, and as you mentioned, I have the RC in filters at the RCA's.
I should get it done today and will report back.
Sandro, thanks. The coaxial is to decrease outpu/input coupling within the box because the lenght of the wires happpened to be kind of long. As far as RF, the housing is connected (should be) to Star-GND, so the whole assembly is shielded, and as you mentioned, I have the RC in filters at the RCA's.
I should get it done today and will report back.
Reporting on the completed NIGC.
Everything is just fine. No oscillations, it doesn't even worm-up at the levels I listen to it. The speakers are 90dB/w/m.
It sounds like one eager to run boy. Fast and detailed, not harsh (to me at least). Base is plenty. Again it will depend on the listening level, but at any reasonable (higher than I could ever listen to) level sounded fine in the base section.
So far I've listen to the type of music like Diana Krall, James Taylor, Sting, Classical. Everything as I said sounds very vibrant. I'll check it on Destiny’s child and see how it goes with more complex music.
Output offset is 2.5 mV on one and -12mV on the other one. I guess I didn't pick well matching IC's but it's not a big deal at all. The noise level is very low. You ear has to be at the speaker to hear tiny hisss.
So far very pleased with the results.
More updates later.
Greg
Everything is just fine. No oscillations, it doesn't even worm-up at the levels I listen to it. The speakers are 90dB/w/m.
It sounds like one eager to run boy. Fast and detailed, not harsh (to me at least). Base is plenty. Again it will depend on the listening level, but at any reasonable (higher than I could ever listen to) level sounded fine in the base section.
So far I've listen to the type of music like Diana Krall, James Taylor, Sting, Classical. Everything as I said sounds very vibrant. I'll check it on Destiny’s child and see how it goes with more complex music.
Output offset is 2.5 mV on one and -12mV on the other one. I guess I didn't pick well matching IC's but it's not a big deal at all. The noise level is very low. You ear has to be at the speaker to hear tiny hisss.
So far very pleased with the results.
More updates later.
Greg
Attachments
...congrats again.
Seasonal boxes
If you have Peter Daniel’s box making/ craftwork skills, ignore:
I have zero metalwork experience, but am soon to build two ‘gainclones’ (one 3886, one TDA 7293).
With Christmas here, the number of tins for lollies, chocaltes, coffee, biscuits etc is about 5+ times normal. Here in Oz, I found a great range at K-Mart. I got a large one for the PS, and a small one for the amp.
Only 15 shopping days to go . .
Anyone else done this? Strike any problems??
Cheers
If you have Peter Daniel’s box making/ craftwork skills, ignore:
I have zero metalwork experience, but am soon to build two ‘gainclones’ (one 3886, one TDA 7293).
With Christmas here, the number of tins for lollies, chocaltes, coffee, biscuits etc is about 5+ times normal. Here in Oz, I found a great range at K-Mart. I got a large one for the PS, and a small one for the amp.
Only 15 shopping days to go . .
Anyone else done this? Strike any problems??
Cheers
The boxes for the power supply are very thin. The transformers are quite heavy. That’s the only think to consider when buying the boxes. Second is the fact that you’ll have to attach the IC to something a bit stiffer than just a tin box to have a good thermal contact and low thermal resistance. And the last the cables are quite heavy so you’ll need some wall stiffness where the connectors are installed.
That's all I can think of right now.
That's all I can think of right now.
Greg is the gainclone still performing to your expectations ?
Reason for asking is , my colleague and I have just completed a bass reflex box for a pair of Fostex 206 E
Powered by our existing amp the highs were too prominent, there was a lack of bass. Not nice.
We then added a notch filter as suggested by
http://home.hetnet.nl/~geenius/Solo206.html
Major and pleasing improvement But we know speakers and amps have to be matched.
So the next step is a gainclone, but it doesnt have to be a super minimalist design so we were thinking of using your schematic.
Cheers
Reason for asking is , my colleague and I have just completed a bass reflex box for a pair of Fostex 206 E
Powered by our existing amp the highs were too prominent, there was a lack of bass. Not nice.
We then added a notch filter as suggested by
http://home.hetnet.nl/~geenius/Solo206.html
Major and pleasing improvement But we know speakers and amps have to be matched.
So the next step is a gainclone, but it doesnt have to be a super minimalist design so we were thinking of using your schematic.
Cheers
sandro600 said:
Sandro,
No complains so far. Nothing has changed in the way it sounds. I like it. It has very clear highs, and mids and the base is just fine. I’ve been listening to it since and not planing to even tweak it.
You can use the sch. I have there, so far no problems at all.
Tell us how it sounds.
Nice speackers!
Have fun!
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