Gieseler Audio Posted February 7, 2019 Share Posted February 7, 2019 (edited) Hi everyone, I have been working on a new headphone Amplifier which is finally ready - in stock & priced at $600. Additionally as it includes RCA line outputs, it can also function as a basic preamp. Technical highlights. Power supply - I have gone totally overboard here as in my opinion the power supply has a major effect on the sound quality. Power diodes are a special low radiated noise, very soft recovery types. Main filter capacitance is a massive 40,000uf using the Nichicon "Gold Tune" KG series, designed specifically for high grade audio equipment. Internal regulators are low noise fast transient response Linear Technology devices. These are the same series regulator as the one the Kraftwerk PSU uses. Amplification is composite design using a LME49600 diamond buffer running in class A coupled to a Muses J-FET operational amp, which also designed specifically for use in audio. At $18 each they cost significantly more than most op-amps. Gain can be switched between 2x or 6x to cover low or high impedance headphones. RCA sockets are Switchcraft & gold plated. Power input is from a dual output 9v + 9v external transformer. The volume control is a plastic film unit so should have long life. Relay muting so the unit won't produce any turn on/off pops. Input impedance is 20k so a nice easy load. Audio bandwidth is very high & distortion extremely low. I will post some tech results shortly. I have just done some quick output level measurements. Very basic setup with a 1k sign wave, monitoring on a digital scope & taking the voltage measurement just under clipping. All reading are RMS Milliwatts into stated load. Into 8 ohms 348 12 ohms 468 16 ohms 548 33 ohms 720 600 ohms 50 As soon as time permits I will take some more precise measurement. Edited February 7, 2019 by Gieseler Audio added info 9 1 Link to comment Share on other sites More sharing options...
Guest Benjet Posted February 7, 2019 Share Posted February 7, 2019 Hi everyone, I have been working on a new headphone Amplifier which is finally ready - in stock & priced at $600. Additionally as it includes RCA line outputs, it can also function as a basic preamp. Technical highlights. Power supply - I have gone totally overboard here as in my opinion the power supply has a major effect on the sound quality. Power diodes are a special low radiated noise, very soft recovery types. Main filter capacitance is a massive 40,000uf using the Nichicon "Gold Tune" KG series, designed specifically for high grade audio equipment. Internal regulators are low noise fast transient response Linear Technology devices. These are the same series regulator as the one the Kraftwerk PSU uses. Amplification is composite design using a LME49600 diamond buffer running in class A coupled to a Muses J-FET operational amp, which also designed specifically for use in audio. At $18 each they cost significantly more than most op-amps. Gain can be switched between 2x or 6x to cover low or high impedance headphones. RCA sockets are Switchcraft & gold plated. Power input is from a dual output 9v + 9v external transformer. The volume control is a plastic film unit so should have long life. Relay muting so the unit won't produce any turn on/off pops. Input impedance is 20k so a nice easy load. Audio bandwidth is very high & distortion extremely low. I will post some tech results shortly. I have just done some quick output level measurements. Very basic setup with a 1k sign wave, monitoring on a digital scope & taking the voltage measurement just under clipping. All reading are RMS Milliwatts into stated load. Into 8 ohms 348 12 ohms 468 16 ohms 548 33 ohms 720 600 ohms 50 As soon as time permits I will take some more precise measurement. Looks nice!! Bad timing for me as I’ve just bought a new HP amp [emoji854] Link to comment Share on other sites More sharing options...
Suopermanni Posted February 7, 2019 Share Posted February 7, 2019 Do I need to ask if there is going to be a higher end model? I think there will eventually will be one! Link to comment Share on other sites More sharing options...
custom_made Posted February 7, 2019 Share Posted February 7, 2019 No cool name for this one, Clay? Link to comment Share on other sites More sharing options...
Gieseler Audio Posted February 7, 2019 Author Share Posted February 7, 2019 Hi guys, Richard you are way ahead of me - I’m already thinking of a higher end model but I thought it would be best to start with a basic version. custom_made, my partner initially fired up the German/English Thesaurus but I thought I would keep it simple for a change. However still open to suggestions. Link to comment Share on other sites More sharing options...
Snoopy8 Posted February 7, 2019 Share Posted February 7, 2019 Clay, suggest putting "Gieseler" in front of your topic title. That way, people will know whose product it is ! Link to comment Share on other sites More sharing options...
Gieseler Audio Posted February 7, 2019 Author Share Posted February 7, 2019 Done! Good suggestion Snoopy. Link to comment Share on other sites More sharing options...
Mat-with-one-t Posted February 8, 2019 Share Posted February 8, 2019 (edited) Kopfhörer Edited February 8, 2019 by Mat-with-one-t 1 Link to comment Share on other sites More sharing options...
Gieseler Audio Posted February 8, 2019 Author Share Posted February 8, 2019 (edited) Interesting - thanks Mat Quick update. OK Fein DAC (2v rms out) hooked up to the line inputs & unit being used as preamp into a big T&A power amp. Gain may be a little high - on low gain getting pretty loud at 11 clock & the same with my Audio Technica ATXH-MX50's. Gain on the low setting is 1.8x so I might drop that to 1.5x. Next noise check - super quiet - max vol on high gain I could barley discern the faintest hiss out of the tweeters. Same with headphones - super quiet. Channel tracking & imaging nice. Sound Quality - I'm very happy but I need opinions from you guys so one is going to Benjet soon for evaluation. Also I have done a few more quick bench tests. Line out max level 6v RMS. Line out impedance 15 ohms Frequency response Line out 10Hz to 50KHZ + - .2 dB Phones (does depend on load & level) at 2v out & 33 ohm load 20HZ to 50KHZ + - .3dB Channel is tracking is pretty good with barely a deviation from my twin needle audio millivolt meter. Photo attached of worst case Edited February 8, 2019 by Gieseler Audio spelling 1 Link to comment Share on other sites More sharing options...
Guest Benjet Posted February 8, 2019 Share Posted February 8, 2019 That a pretty cool meter. I use my scope to do that. Link to comment Share on other sites More sharing options...
Gieseler Audio Posted February 8, 2019 Author Share Posted February 8, 2019 (edited) Hi Ben - yes it’s perfect to check volume control tracking. The PDX LDR level matching was hard work so this meter was really usefull with that. You can also use it to measure power supply noise but it’s bandwidth is a bit limited. Edited February 8, 2019 by Gieseler Audio 1 Link to comment Share on other sites More sharing options...
Bill125812 Posted February 8, 2019 Share Posted February 8, 2019 If I used headphones, I would be heading down to see Clay. Everything I’ve bought from him is first class and incrediable value for dollars. This I’m sure will be no different Still don’t know how you make time to do all this mate 2 Link to comment Share on other sites More sharing options...
Guest Benjet Posted February 8, 2019 Share Posted February 8, 2019 If I used headphones, I would be heading down to see Clay. Everything I’ve bought from him is first class and incrediable value for dollars. This I’m sure will be no different Still don’t know how you make time to do all this mate It’s never to late to change teams [emoji6] we here in the headphone community don’t discriminate against those who can’t strap their speakers to their head [emoji106] Link to comment Share on other sites More sharing options...
Bill125812 Posted February 8, 2019 Share Posted February 8, 2019 1 hour ago, Benjet said: It’s never to late to change teams we here in the headphone community don’t discriminate against those who can’t strap their speakers to their head Like this 3 1 Link to comment Share on other sites More sharing options...
Guest Benjet Posted February 8, 2019 Share Posted February 8, 2019 Like this I use a different brand of tape, but you get the idea Link to comment Share on other sites More sharing options...
Guest Benjet Posted February 8, 2019 Share Posted February 8, 2019 7 minutes ago, Bill125812 said: Like this I’m only down the road from you and if you ever feel the urge to have a listen to some cans drop me a pm. We are having a headphone GTG in the near future or you are welcome to drop by whenever. Link to comment Share on other sites More sharing options...
Bill125812 Posted February 8, 2019 Share Posted February 8, 2019 @Gieseler Audio if there is a headphone GTG Close to us Clay. Maybe you could lend them a unit. I might even be tempted to go along. Could even bring my GroB dac for a whirl Link to comment Share on other sites More sharing options...
Guest Benjet Posted February 8, 2019 Share Posted February 8, 2019 Hi Bill,Clay is already suppling a HP amp and also a new, upgraded version of the Fein DAC for the meet. There will also be at least one Grob and it has the new LSP from Clay, I believe. Link to comment Share on other sites More sharing options...
Guest Benjet Posted February 8, 2019 Share Posted February 8, 2019 Meet will be either in Birkdale (my house) or Capalaba (my work), depending on numbers. Link to comment Share on other sites More sharing options...
Gieseler Audio Posted February 10, 2019 Author Share Posted February 10, 2019 Well I decided I needed something better than my Audio Technica ATH-M50X's to evaluate my new headphone amp so I lashed out on a pair of these. I needed closed back so choice was limited but I've always been a fan of Sony's premium products - price good at the moment too. 1 1 Link to comment Share on other sites More sharing options...
Suopermanni Posted February 11, 2019 Share Posted February 11, 2019 (edited) On 09/02/2019 at 8:56 AM, Benjet said: Hi Bill, Clay is already suppling a HP amp and also a new, upgraded version of the Fein DAC for the meet. There will also be at least one Grob and it has the new LSP from Clay, I believe. About the LPSU I have, it might not be the newest design like the one built into the Fein DAC. It's good with both the Klein III and the GroB that I have though! EDIT: If an unit of the HP Amp appears at the meet, would anyone mind if I plug my LCD3s in it? Just want to see if it can run it. Edited February 11, 2019 by Suopermanni 1 Link to comment Share on other sites More sharing options...
Guest Benjet Posted February 11, 2019 Share Posted February 11, 2019 1 hour ago, Suopermanni said: About the LPSU I have, it might not be the newest design like the one built into the Fein DAC. It's good with both the Klein III and the GroB that I have though! EDIT: If an unit of the HP Amp appears at the meet, would anyone mind if I plug my LCD3s in it? Just want to see if it can run it. It’s there for the use of everyone. I’m sure Clay would like as many people to experience his latest creation. Link to comment Share on other sites More sharing options...
krebetman Posted February 12, 2019 Share Posted February 12, 2019 On 08/02/2019 at 12:10 PM, Mat-with-one-t said: Kopfhörer Kopfvergrößerung ? Link to comment Share on other sites More sharing options...
Raffinator Posted March 10, 2019 Share Posted March 10, 2019 If a tour unit is travelling, happy to try in Sydney. Desktop setup is for LCD-3 and a pair of Genelec monitors so really keen to utilise all features. Will be up against a Schiit Mjolnir II. Link to comment Share on other sites More sharing options...
Gieseler Audio Posted March 10, 2019 Author Share Posted March 10, 2019 Hi John, ok sounds like a good plan so I will get one shipped out to you this week to try. Link to comment Share on other sites More sharing options...
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