Rerurn to Romy the Cat's Site
In the Forum: Melquiades Amplifier
In the Thread: 6 Channel Version of Super Melquiades
Post Subject: Super Milq 6 channels diaries: #9 – HF response.Posted by Romy the Cat on: 9/5/2007
I was kind of frustrated with some strange high frequency roll off at my HF and Injection channels. It should not happen. The 9H OPT LL1627 in Injection channels should be good up to 23kHz according to my former tests with a full range Milq and the Tribute’s OPT with 4H primary and limited amount of turns should be much more extended into HF.
So, I figures that I might be my TRA lied at HF – I did not celibate it before I measured it. So, I run it into the scope and it looked very good exactly - how I expected. Take a look – it is 3V driven into the Milq and the signal was taken from HF channel.
The first one is the calibration of the amplitude at 10 kHz where the channel is a complete band-pass. I made it 10 squares.
Now let to slide the frequency and see where the high-pass crossover will kick in. 3dB in my case is 3 squares or 1.5 squares from top and from bottom. So, I have minus 3dB around 2750Hz.
Let now to raise the frequency. The 20kHz – it has no impact to amplitude and the channel handles it at 0dB…
Now let to move up frequency until I get the 1.5 squares (3dB) roll off. I happened at 75 kHz – not bad at all… In hardly need it for Vitavox S2 driver but still…
It was my MF channel - I did not test my HF as I have no transformer yet – it is coming. It will be driving the Water Drop ribbon directly form the 6E5P’s plate. It is Amorphous torpid 175:1, turn to foil with primary inductance 180mH, leakage inductance 1.7mH and capacitance between primary and secondary .062nF. It should be fun to listen THAT high frequency
Rgs, Romy the Cat Rerurn to Romy the Cat's Site