All is nothing but my subjective impressions. Not sure what you mean by golden ears, but when my record collection is growing I know music is flowing. When things expand and instruments are rendered finely textured on a black quiet background I know I am on the right track. Perfect oh no, but better absolutely. Increments and steps is all we can ask for, sound is something for HiFi, music is something you feel.
Dear Miib ,I do not discount subjective assessments or mean to denigrate
with the "golden ears" remark.
But , all these sub 50ppm input stages are hard to assess. You seem to
have it right correlating to my own subjective assessments.
I have only heard spooky ,wolverine , and CFA -kypton C.
-Spook has Geddy Lee's (rush) bass lines "nailed" - to die for !!
-Wolverine does Alan Parsons with a sound engineers precision.
- The Kypton C excels with the orchestra (violins , soprano's ).
Listened to all genres on those IPS's - we seem to have the same conclusions.
But , it is close - takes a bit of serious listening to
differentiate between very good and exceptional.
Edit - by "your last IPS" - you mean the 18 device CM'ed one (miib-ae ?)
OS
with the "golden ears" remark.
But , all these sub 50ppm input stages are hard to assess. You seem to
have it right correlating to my own subjective assessments.
I have only heard spooky ,wolverine , and CFA -kypton C.
-Spook has Geddy Lee's (rush) bass lines "nailed" - to die for !!
-Wolverine does Alan Parsons with a sound engineers precision.
- The Kypton C excels with the orchestra (violins , soprano's ).
Listened to all genres on those IPS's - we seem to have the same conclusions.
But , it is close - takes a bit of serious listening to
differentiate between very good and exceptional.
Edit - by "your last IPS" - you mean the 18 device CM'ed one (miib-ae ?)
OS
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"voicing" IPS's ...
Since Mr. Miib got me going ....
I have included extra compensation pads and those VAS-ground shunts
on all my IPS's.
At the expense of low THD , one can "constrain impedance" at the VAS
output. The symasui does this , plus can shunt HF to ground .
Usually , I specify 220K -680K for the resistor shunts. Drop this 22K-68K ,
H2 usually rises.
Objectively , the simulator opposes this "blasphemy". Subjectively ,
the higher THD "voiced" IPS might be more to ones "liking".
PS- I straddle the fine line between subjective/objective , as my
brain and ears tell me this fine line IS real.
OS
Since Mr. Miib got me going ....
I have included extra compensation pads and those VAS-ground shunts
on all my IPS's.
At the expense of low THD , one can "constrain impedance" at the VAS
output. The symasui does this , plus can shunt HF to ground .
Usually , I specify 220K -680K for the resistor shunts. Drop this 22K-68K ,
H2 usually rises.
Objectively , the simulator opposes this "blasphemy". Subjectively ,
the higher THD "voiced" IPS might be more to ones "liking".
PS- I straddle the fine line between subjective/objective , as my
brain and ears tell me this fine line IS real.
OS
OS,
Did H/K do some of what you are talking about to increase the 2nd harmonics. I have noticed that the H/K has a warmer sound than many other SS amps. You surely don't need any measurements to hear the difference between the H/K and a Parasound, they are night and day different.
Did H/K do some of what you are talking about to increase the 2nd harmonics. I have noticed that the H/K has a warmer sound than many other SS amps. You surely don't need any measurements to hear the difference between the H/K and a Parasound, they are night and day different.
Thanks, I did mil spec and it was bad enough, with a tough inspector...the did not show the Teflon striping tool that burned the insulation off of the wire😛
Yes , both the 680/990 shunt the heck out of the VAS. Mr. Cordell would call
this "abuse".
Many OEM VAS's "shunt like hell" .
Objectively , this would constrain the impedance variations vs. frequency (or load , in an EF2).
And for sure ... it abuses the resulting THD (by adding more).
The objective guru's would hang me for saying this might make for better
SQ. (Mr. self would call me an idiot 😀)
ALL hi-end audio is some sort of "trade-off".
OS
this "abuse".
Many OEM VAS's "shunt like hell" .
Objectively , this would constrain the impedance variations vs. frequency (or load , in an EF2).
And for sure ... it abuses the resulting THD (by adding more).
The objective guru's would hang me for saying this might make for better
SQ. (Mr. self would call me an idiot 😀)
ALL hi-end audio is some sort of "trade-off".
OS
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I guess I would be one of those who rather likes the H/K sound, don't really like the sterile sound of the Parasound amps.
- HK680 = shunted symasui IPS (w/ slew mini ops)
- HK990 = shunted spooky (with the 5p OPS)
In fact ,only difference is the spooky's LED CCS's.
A spooky/slewmaster combo is a 680/990 combo.
I own the 680 , and have repaired/heard the 990.
What I have now exceeds both.
Like HK , build a slewmaster. New slew with mt-200's is a 990 +++.
OS
- HK990 = shunted spooky (with the 5p OPS)
In fact ,only difference is the spooky's LED CCS's.
A spooky/slewmaster combo is a 680/990 combo.
I own the 680 , and have repaired/heard the 990.
What I have now exceeds both.
Like HK , build a slewmaster. New slew with mt-200's is a 990 +++.
OS
Hi boris,please post Eagle files here.🙂
An alternative pcb is always useful.
Bimo want ARTA measurements,Spectra lab is the same thing.
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Files bellow with some modyfication it will fitt to any OPS.
I just drawn it while ago and it is not tested.
Edit:
I have forgotten to add 100R--2.2pF network for compensation.
Bellow corrected files.
I just drawn it while ago and it is not tested.
Edit:
I have forgotten to add 100R--2.2pF network for compensation.
Bellow corrected files.
Attachments
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OEM's must know about this "unmeasurable" fact , as well.
Just about all the class AB sub amps are a simplified "Spooky"
with a EF2 OPS.
OS
Just about all the class AB sub amps are a simplified "Spooky"
with a EF2 OPS.
OS
Spooky = Leach right? A proven design. Simetri is similar. The low end is evident on the scope. There is a reason that Dr Leach used this design to teach his students. He got it right.
Now we have all these great IPS modules, could we select the best and optimize for optimal Sound quality, do some research on how to optimize, PCB layout, capacitors selection, all the small things that gives 'silk' with 'dark' background sound??
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Kim, sorry but class D is good at everything but the Bass, and please do your own findings, this is DIY, not spoon feeding, everything is here, make your choices and do the work. I have spent more than 10 years working and learning. Curl spent a lifetime, so much expirence and information is gathered here examine and learn, your request shows that you really just want the easy way out, Circuit is less than 10% of the final result, the devil is n the detail.
Went to a Rush concert in 1990 with all Class AB as power (man , all those
heatsinks - wall of them).
Went to a Eagles concert with various new class D (even lab gruppen's) in
2005.
Of the two 50Kw+ concerts , Rush's sound was so much better. I had to distance
myself from the harsh sound of the Eagles. I like the Eagles , but not
their sound system.
Besides the "police state" atmosphere , just about everything "21'st century"
sucks. The concerts - the amps. CLASS D !!
This is why I bring you the best of the late 20'th century designs.
Nope ... everything is going right downhill ( 2005 on , especially).
Hopefully , we can preserve the best of 1970-1990 (when the "good stuff
was designed).
OS