matthew-levi

Thank you for the amp schematic. Do you know where I can get the PSU schematics. I have looked thought the dropbox and Google Drive posted by KG but does not seem to be able to locate the PSU. I thought there are others who have build non pro version. BTW, your info addendum is very useful, thank you for that.

Hi, I am a newbie to this forum and I am late to the party. I only find out this forum and thread recently. I have a Stax Lambda (non pro version) for many years and have been using a SRD-7 to listen to music. But I have always wanted a direct drive amplifier for this headphone. So when I found this forum and the KGST thread, I was thrilled and decided to join the party even its late. I have contacted Birgir recently and bough a set of boards from him. I know I will need help for this community to put this amp together and I am reaching out to the members (especially the experienced and advance members) who have much more experience in this than me to give me a helping hand, much appreciated. I do have some experience in building amplifiers (tubes included). The first help I need is to find the most recent schematics for the KGST amplifier and its PSU. I know there has been some revisions since the beginning. If someone can point me to where I can find them, I would greatly appreciate.

Does anyone has any experience in upgrading the trafos on the SRD 7 and what were the results. Interested to hear any experience out there.

The transformers in SRD 7 are not isolation transformers. I have measured the input voltage (from the amplifier loudspeaker terminal) and the SRD 7 transformer output voltage to the earphone. I put a 1Khz 1 volt input into the transformer and the output is about 36 volts. So its a step up transformer.

I am new to this forum, so if the question below have been answered, please bear with me, and help point me to the post. I have an Stax Lamda and SRD 7 combination. Recently I opened up the SRD 7 to take a look inside and found the two transformers quite anaemic. I thought may be the performance of the SRD 7 could be better if we use a better transformer. I am using an Audio Research VS115 power amp to drive it. Looking the schematic, it looks look the transformers are like tube output transformers. Does anyone have any idea about what spec those transformer would be like, primary impedance (facing the loudspeaker output from the amp) vs secondary impedance (facing the stators). Would a 10K : 8ohm push pull output transformer be suitable for this, just want to experiment. Any advice would be appreciated.

I have an Stax Lamda and SRD 7 combination. Recently I opened up the SRD 7 to take a look inside and found the two transformers quite anaemic.I thought may be the performance of the SRD 7 could be better if we use a better transformer. Looking the schematic, it looks look the transformers are like tube output transformers. Does anyone have any idea about what spec those transformer would be like, primary impedance (facing the loudspeaker output from the amp) vs secondary impedance (facing the stators). Would a 10K : 8ohm push pull output transformer be suitable for this. Any advice would be appreciated.