Very nice build!
How's that? Mine does exactly the opposite. OK I have used a little higher heatsings for the DCSTB but each half feeds one DCG3 module - two channels biased @ 112 mA. Even so, I would hardly call it warm. The DCG3 heatsink on the other hand - common for four channels - needed to be extended as it went scary hot in the summer.
Thanks for the kind words. My amp sink is 0.9C/W so should be able to handle 150mA bias according to the build guide. But wouldn’t increasing the bias also put more stress on the PSU? And what is the expected effect of this change sound wise on HD6XX cans?
My understanding of the build guide was 150mA bias for low impedance cans which I am not planning to connect a regular basis.
Just trying to learn from all of this and willing to try higher bias.
Thanks again
Steef
My understanding of the build guide was 150mA bias for low impedance cans which I am not planning to connect a regular basis.
Just trying to learn from all of this and willing to try higher bias.
Thanks again
Steef
If you went with a Galaxy maggiorato (80mm X 280mm), I had the same experience in the summer. I had to put an extra aluminum plate which kept the temperatures in acceptable degree.
In the case of your 35Ω ATH-MSR7 it would have helped* When not planing to use it regularly or critically, no worries. Yes the PSU sinks would get hotter at 150mA bias but you shouldn't be afraid of temperatures below 65C on those sinks since the MJE BJTs there are robust types. Unless their dissipation would up the small box's ambient temp uncomfortably high. Depends on its ventilation too.
*See the last two THD sweep pictures in post#1 on 32 Ohm Grado cans used as real load between 100mA and 150mA bias. The can's own THD would probably swamp those differences but anyway. The ATH sounds alright to you even at 100mA as you already mentioned.
Although I like small footprint builds, I couldn't go that way for my DCG3. I used a big diy box and two heatsinks connected with heatpipes. I can understand the necessity of this especially for greek summers. My query is why the DCSTB runs so cool. Perhaps Steef is using higher output transformer?
Hi, Some build details
- 2x18V 50VA toroidy transformers
- Galaxy Maggiorato GX285 230 x 350 mm 10mm front panel case
- Heatsinks on DCSTB from kit
- Heatsink for amplifier 6506G 0.9 C/W from Reichelt
Steef
Maybe in the forties Celsius. Does your DMM have a temperature scale and a thermocouple wire probe so to can measure the sinks?
I am not that an analytical listener that I can tell that it opened up. What I did hear that this amp was much more open than a well seasoned Shiit Jotunheim after only a couple of hours playing.
The Net considers the Jotunheim among the best matches for the HD650 so I am a happy builder
Just listened to Adrift from "Music To Draw To: Satellite" from Kid Koala/Emiliana Torrini and was amazed by the head-filling bass tones combined with the airy voice of Emiliana and the twinkling music tones accompanying her.
The Net considers the Jotunheim among the best matches for the HD650 so I am a happy builder
Just listened to Adrift from "Music To Draw To: Satellite" from Kid Koala/Emiliana Torrini and was amazed by the head-filling bass tones combined with the airy voice of Emiliana and the twinkling music tones accompanying her.
Jotunheim must be something like Magni 3's daddy then
I have Sen HD 600 among other cans and its doing pretty alright on 100mA DCG3 bias so no worries with your HD 6XX either. I stick 32 Ohm Grado SR60 cans to it also from time to time but because my 30VA encapsulated trafos are somewhat inefficient I avoided the 150mA choice. But I don't care to listen much critically with any model that's below 80 Ohm in my current collection. I don't have any much worthy low Ohm one.
I have Sen HD 600 among other cans and its doing pretty alright on 100mA DCG3 bias so no worries with your HD 6XX either. I stick 32 Ohm Grado SR60 cans to it also from time to time but because my 30VA encapsulated trafos are somewhat inefficient I avoided the 150mA choice. But I don't care to listen much critically with any model that's below 80 Ohm in my current collection. I don't have any much worthy low Ohm one.
Hi Salas
I just got my kit from Tea-Bag, and I'm going to get some some Toroidy trafos.
Would you recommend 17V over 18V in all cases? I'll be using as HPA with 150mA bias.
Thanks