intactaudio

Responses from intactaudio

Any Members Tried the Audio Interface CST-80 SUT?
When it comes to transformers the two main factors to be designed around are the source and load impedances.  In the case of a SUT the source is a cartridge and the load is the phono stage.  This means that the cartridge impedance is the main fact... 
Mono recordings - two questions...
 The modifications can be as simple as internal summing of connections, or as complex as reorienting the pair of existing stereo coils.  With either (or both) the cartridge still responds to and generates a signal from vertical content which can p... 
autoformer attenuator and step up transformers
-5dB 
autoformer attenuator and step up transformers
the perfect position for the autoformers is full volume then they are simply a shunt element.  The worst performing taps are in the 0 to -6dB range but they still have 100Khz+ bandwidth and what ringing there is is also above 100khz which is far e... 
autoformer attenuator and step up transformers
Placing the 1:4 in front of the autoformer would increase the source impedance to 6.2K which would then be reduced by whatever attenuation is needed.  This added 12dB of gain would be offset by anything over 12dB of attenuation adding lots of comp... 
autoformer attenuator and step up transformers
If I were to use a step up and autoformer combo I would place the 1:4 after the autoformer and arrange it so it is only used when it is absolutely needed.  dave 
Elrog 300B vs Takatsuki 300B tubes
What I am referring to is the filament voltage at turnon and this has little to do with the value of the cathode resistor.  If the filament glows brighter at first and then settles down to "normal" it is being unduly stressed on turnon.  This goes... 
Elrog 300B vs Takatsuki 300B tubes
May it be that the filaments of the Elrogs are very bright after switching on the amp for 2 or 3 seconds and then the brightnes is decreasing within the next about 5 to 10 seconds?Brightness on turnon that slowly dies down is a sign of overvoltage... 
Phono stage w/automatic Load-Impedanance.
Allen was a big proponent of using the "Neumann" time constant in his designs which shelves the response with a corner at 50Khz. Using a "normal" riaa puts the info at 750Khz about 32dB below the value at 20Khz but including the "neuman" drops tha... 
Phono stage w/automatic Load-Impedanance.
heyThe cartridge is not physically generating at these frequencies.Agreed....It's an electrical resonance at a particular frequency which can cause overload or oscillation.doesn't this contradict your first statement? In order to excite a resonanc... 
Phono stage w/automatic Load-Impedanance.
I have simulated it using J_carrs model and indeed considering the simple ideal model a MC cartridge can in theory resonate with cabling capacitance in the Mhz range. However in spice, you are feeding a signal from a generator that has no problem ... 
Phono stage w/automatic Load-Impedanance.
Can someone please tell me how this resonance in the MHz range is being excited? dave 
cartridge demagnetization
Lyra carts such as the Delos use a paramagnetic grade of iron for the coil formers, i.e. will "conduct" magnetism but resist storing it, so residual magnetism should be minimal anyway?I think you mean "soft magnetic" instead of paramagnetic.dave 
Is it worth refurbishing my tube Marantz?
In any case look at the tubes inside. Sid used the telefunken ecc803s in many of these and the tubes inside may match the value of the 7C.dave 
NAGATRON HV9100
Well Vinyl Engine says it was $400 new but doesn't mention if the pre-preamp was included. It also mentions that it is "rare" I for one would like to hear any info on this cartridge and have been digging with little real info being found.please gi...