Cheeseheads FTW! I've been struggling for a long time to come across some 3mm ones.
Nice amps here!
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I've been working on this one in the background while I build other amplifiers. It's a constant project. I posted this in my 135W 8 / 270W 4 thread, but it doesn't reach those levels. It will in the near future. I'm getting there.
But this one is lovely - VERY quiet, and sounds good so far. Future PCBs will be neater. I like this design very much.
But this one is lovely - VERY quiet, and sounds good so far. Future PCBs will be neater. I like this design very much.
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Since past few yeares I can not finish up any of my amplifiers, enclosure is open, amp not complete and I am digging in it.
But I have promissed myself that before end of the year I will finish one of them
sajti
Where did You got the enclosure ''box'', I presume there is top lead and front panel too for it.
I will need a standard steel one (without radiators like).
Regerds Pit
But I have promissed myself that before end of the year I will finish one of them
sajti
Where did You got the enclosure ''box'', I presume there is top lead and front panel too for it.
I will need a standard steel one (without radiators like).
Regerds Pit
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Hi,
this is standard 2U high rack box, made in Hungary. 400mm deep, and made by 1,2mm steel, with perforated front for fan cooling. The cost is about 35Euro.
Not really high end, it has industrial look, but I prefer it, especially the low height.
Sajti
Best headphone amp I have ever heard. Finally in stereo with cross feed filter.
http://www.diyaudio.com/forums/pass-labs/271926-f5-headamp-72.html
http://www.diyaudio.com/forums/pass-labs/271926-f5-headamp-72.html
Member
Joined 2009
Paid Member
I'm jealous ! - I built a great headamp myself (http://www.diyaudio.com/forums/headphone-systems/275180-grasshopper.html) but I just can't get along with headphones. Unless I"m on a plane with noise cancelling things I just can't have them on my head. I've tried closed back and open back to no avail.
It's a shame because headphone amplifiers allow us to indulge in Class A without too much expense or hassle with simple circuits of exceptional performance. Mine was so transparent that I never could identify a 'sound' with it. I may have to rescue it as a pre-amp.
It's a shame because headphone amplifiers allow us to indulge in Class A without too much expense or hassle with simple circuits of exceptional performance. Mine was so transparent that I never could identify a 'sound' with it. I may have to rescue it as a pre-amp.
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You might try the simple crossfeed filter that I am using. It helps open the soundstage and adds ambiance so you don't feel like the band is playing in between your ears.
If you have a high impedance input this filter can probably work. Easy enough to make and doesn't hardly cost anything.
http://www.diyaudio.com/forums/atta...f5-headamp-f5-ha-using-passive-cross-feed.pdf
I like your grasshopper design. 3 transistors even more simple than F5's 4 which I thought was already minimalist. The F5 HA has some nice drive ability though with IRF620/9610 MOSFETs can definitely do an 8ohm load. In fact I tested it on Fullrange Faital Pro 3FE22 in a ported box and was decent sounding.
If you have a high impedance input this filter can probably work. Easy enough to make and doesn't hardly cost anything.
http://www.diyaudio.com/forums/atta...f5-headamp-f5-ha-using-passive-cross-feed.pdf
I like your grasshopper design. 3 transistors even more simple than F5's 4 which I thought was already minimalist. The F5 HA has some nice drive ability though with IRF620/9610 MOSFETs can definitely do an 8ohm load. In fact I tested it on Fullrange Faital Pro 3FE22 in a ported box and was decent sounding.
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Joined 2009
Paid Member
That wasn't the issue, I just don't like having things on my ears, on my head like that.
Why drive 8 Ohm - what kind of headphones are those ? For speakers, there can be dips below 8 Ohm and phase angle can drive current higher than you think so it's really a power amp you need - many different choices there. You can use just one device if you like; the SEWA amp is another simple design that was very highly rated.
First, thank you, guys for the warm words.
My wife did not believe that I finish it ever
To be honest, I do not know how to add big images - I put them into gallery, but can not find link name. And case even small - inside 2x 1000VA James Audio transformers, 4x RIFA PEH200 100000uf x 80V capacitors, I wanted to put bigger Kendeil caps for driver rectifier, but had to put small (8x 6800uf 100V) - no place. And heat sinks are not enough big - I have 54C temperature (BIAS of current amplifier 1.2A, power +/- 60V)
Inside my amp - My Photo Gallery
My wife did not believe that I finish it ever
To be honest, I do not know how to add big images - I put them into gallery, but can not find link name. And case even small - inside 2x 1000VA James Audio transformers, 4x RIFA PEH200 100000uf x 80V capacitors, I wanted to put bigger Kendeil caps for driver rectifier, but had to put small (8x 6800uf 100V) - no place. And heat sinks are not enough big - I have 54C temperature (BIAS of current amplifier 1.2A, power +/- 60V)
Inside my amp - My Photo Gallery
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Dear Mrcloc,
Thank you for the warm words - but if not me - modushop.biz made the case by my draft - and they made really good job. They only missing internal steel plate for 500 mm deep case - they offer 400 mm plate - I took it, no choice: 3mm aluminum bottom plate will tot be able to hold two 10 kg transformers.
I would like to hear opinion, is 54C heatsink temperature too high (room 23-24C) or acceptable - Erno Borbely wrote in his manual that up to 55. The amplifier schematic - Borbely Millenium 200W, output stage has 8x (K1058 + J162) matched.
Thank you for the warm words - but if not me - modushop.biz made the case by my draft - and they made really good job. They only missing internal steel plate for 500 mm deep case - they offer 400 mm plate - I took it, no choice: 3mm aluminum bottom plate will tot be able to hold two 10 kg transformers.
I would like to hear opinion, is 54C heatsink temperature too high (room 23-24C) or acceptable - Erno Borbely wrote in his manual that up to 55. The amplifier schematic - Borbely Millenium 200W, output stage has 8x (K1058 + J162) matched.