Quote: Originally posted by N@Z Joe, is it possible to get a copy of the schematic for the MG Head OTL (previous version) I bought mine used a while back & I'm thinking of upgrading the Capacitors, resistors & pentiometer by someone & he says he needs the schematics. MG-Head...

Quote: Originally Posted by EvilJan http://frank.pocnet.net/sheets/062/e/ECLL800.pdf I'm sorry that the datasheet is written in german, but I think you will understand what is written there. If you have any problems understanding this, ask me, I'm german too some websites say...

Quote: Originally Posted by nikongod increase BOTH size and voltage rating of c14&15. in normal operation, the voltage is good, but if the top triode fails, the cap can see b+. 100uf is way small for a 32 ohm load - 470/350V caps are not tooo expensive. - You are right. We will use 250V...

Quote: Originally Posted by amphead Welcome Back Joe Lau! Looks like a good circuit! No beginners however, due to the high voltage. It takes some practice to safely build HV amps. The tubes are fixed bias, so one less step to complete the circuit. Edit: Are you doing a pcb version or...

Quote: Originally Posted by EvilJan Looks very simple. I think it would be a good start into tubes, am I right? But I found some minor failures in the Picture.. The parts list says that VB1 is a 12AX7, and right after that comes VB1,2,3 6DJ8. Should'nt it be only VB2 & 3? Also i'm a...

Quote: Originally Posted by Negatron You might want to price the ECLL800 before you use it in a DIY project, they may sell for enough to buy quite a few suitable tubes. Most any triode or triode wired pentode with a high gm and low rp will work fine as outputs. The $2 Russian 6H6P is a...

Quote: Originally Posted by EvilJan Looks very simple. I think it would be a good start into tubes, am I right? But I found some minor failures in the Picture.. The parts list says that VB1 is a 12AX7, and right after that comes VB1,2,3 6DJ8. Should'nt it be only VB2 & 3? Also i'm a...

New circuit of OTL amplifier , Easy to DIY - pattern in China This structure can be apply on difference tubes like 6H30 , 2A3 , 300B , 6H6 ...... or any load impedance tube. Use 6H30 , 2A3,300B can drive 32 Ohm Headphone to very high level & good sound. This circuit is for DIY only , not for...

First shipment already ship more than 1 month before. I think it arrived NA for a While. New shipment will be ready to ship next week.

It is no difference in OTL mode.

Mk III also improved Output transformers to wider band width. Main Chassis also improve to extrude aluminum chassis with 3mm Thickness. It will not have uneven chassis. crocking panel.

Quote: Originally posted by Born2bwire Probably has more to do with Divergent Technologies, the North American Distributor, than ASL itself. Believe me, dealing with Joe Lau and ASL is worlds apart from dealing with Divergent. For some reason I think that somebody picked one up in Hong...

Just go 12AX7 if you need more gain. OTL32 had no feed back. It is no degrade sound when you use high gain tube.

Today is 15/1 (Chiness Calendar). It is my birthday. It is lover day in China. Lady can not go outside in hundred years ago except this day. So Man and lady can go out side for looking lovers. It is China Valintine day. Happy Chiness Valintine day.

Thank very much for my friends. I will design more better Headphone amplifiers and keep it in reasonable price. OTL Mark III for Divergent order is in production. It may be arrived N.A 45 days to 60 days later.

1. Extrude aluminum main chassis with 3mm Thick 2. Extrude aluminum Power chassis with 3mm Thick (MK IIis plastic) 3. With IEC Socket 4. 10mm Front Panel with Gold Plate screw Fixed. (Anodizing in black color like AQ series). 5. Better Output improve band width to much better in...

50W is OK

It is active pre-amps if you use it as a Pre-amps but V.R is locate at input only. May be can say it only a Volumn control and follow by a driver tube when use as Headphone amps.

It is an metalized in oil cap. It sound may is difference from PIO capacitors.

It is major for converet you amplifiers to Headphone with safety power to avoid damage your headphone and your ears. It is difference from jusr series a resistors with headphone. It will not increase output impedance and not limited in current.

6BQ5 connect in Psudo triode cathode follower. Grid wit a resistor to ground.

I had design a very simple hybird buffer. It is very simple. A 6BQ5 Cathode follower direct coupling to a IRFP150 and capacitor coupling to 32 Ohm Headphone. It is simple , low cost and sound good for Low impedance Cans. It can drive high impedance Cans if you connect it to pre-amps output.

No !It have 1 Output only but can change impedance by a 6 Step transformers.

May be can request an review sample to compare with MG-Head OTL

It seem to be a strange problem. AKG1000 Jack is parallel with normal Headphone jack. No any resistor between it ! AKG1000 is most difficult to drive Headphone. Can drive AKG1000 sure can drive HD600 ! Why ? e.g If OTL32 only output 3V only. It will output (3 * 3) / 120 = 75mW - 75mW Sure can...