arielext
Headphoneus Supremus
'2' is around 8 o'clock if I am not mistaken
Yes'2' is around 8 o'clock if I am not mistaken
Hmm. The SRM-T1/006 series are generally considered ideal amps for the Lambda series, which includes the L-300 as one of the current iterations. It may be that you are demanding too much volume, which could damage you hearing in the long run. So one possibility is to just accept the limit as being what is safe for your ears long term.
Two o'clock on the volume control is really pretty high, although to some extent it also depends on the output of your sources. However, what may be happening is that you are running into the limits of the amp. In the case of the T1 the limiting factor is the output resistors, which are 66 kilohms and suck up the majority of the signal current by Ohm's law V = IR, where V is voltage, I is current, and R is resistance. The output resistors in fact use more current than the headphones, which have a higher impedance - the L300 has a rated impedance of 145 kilohms at 10 kHz, and progressively higher at lower frequencies.
Replacing the output resistors with constant current sources greatly alleviates this problem, as constant current sources do not burn up any significant signal current, thus allowing the output tubes to send significantly more signal current to the headphones. I published an article on this in AudioXpress magazine July 2017 which discusses this in some detail. One thing that was left out of the article but is highly recommended is the addition of 5 megohm bias resistors between the last bias supply capacitor and the output socket. These can be interposed where the bias supply wires go from the circuit board to the output socket. For further discussion of the sonic results of this mod, check out the posts between Muffinhead and myself from Jan and Feb 2018 in this thread.
Hi, thank you for the detailed reply. I find that '2' on the volume pot (Eight o clock) isn't quite loud enough for me it's about medium volume. I don't suppose you could go into more detail about the constant current sources you talk about (sorry I'm quite new to electronics, only really been following guides online and know how to use a soldering iron). Is it possible to list exactly what I would need to replace them with? Thank you again for the reply.
Edit:
After some more experimentation I think I might have found the issue, the earspeakers themselves, I bought a showroom pair of L-300 whilst my amp was being repaired so I wasn't able to test them for a while and having just testing the amp with my lambda signatures which sound fine past eight o clock on the volume I am going to ask for a replacement pair of new L-300's and report back.
Wow, they put your article on the cover of the magazine..
OK, I thought you were talking about 2 o'clock on the volume pot rather than '2' (8 o'clock) which is really quite low. Does sound like your headphones are the problem. However, if that turns out not to be the case, and you are still interested in the mod, you need to get the article by ordering the July 2017 back issue from the AudioXpress website.
LOOOOOL , hes not saying anything at all! The mafia must ha snatched him off his porch the next morning..Man if you tell me there is a new stax model coming out.... Just when you think your at the end.
Any of you compared the 007 MKI and MKII? If so what are your thoughts about the differences? Thanks
God i hope this new stax omega isn't pric over 6K....Man if you tell me there is a new stax model coming out.... Just when you think your at the end.
Any of you compared the 007 MKI and MKII? If so what are your thoughts about the differences? Thanks