jameshillj said:
Good news! It looks everything is okay now, even with my ears!
One thing at a time:
1. I found my mistake in grounding (just one cable to much) and weak ground connection at one of the signal plugs (XLR). The result was very similar to wrong phase at high frequencies. I had a feeling that strong signals are okay whereas weak signals are difficult to locate. I was wobbling like a penguine trying to find ambient center. It was difficult and impossible. I had strange and unpleasant impression that left half of ambient scene is better then right. Something wrong with my equipment or with my ears (wrong with my head, as my wife says - she is right, I know). Uff, it is okay now. More, I am back with C1/C2= Nichicon bi-polars paralleled with Vishay 47nF, I wish I do not have 0.1-0.2 OHm resistors.
2. Good idea, JH, f4 works perfectly with headphones, I am really surprised! Thanks headphones I found weak connector. More: headphones helped me to cancel hum! Easy displacement of some cables and there is no more hum.
Have a nice weekend,
a.
Good to hear "all's well" - the F4 has a nice sound to it - best when running HOT!
Headphones do require more attention to detail than speakers, and when source, amp, cables, etc are "set-up" well, are more capable of superior reproduction.
However, the unnatural sound is not ideal but, as Dave and Protos have said, the Crossfeed tecnique has transformed the problem into an assett.
I'm still surprised that it's not a Universal option, particularly with some of the higher quality, IC based amps.
The Headwize site is the place for more info about Crossfeed systems including the original 1970's Linkwitz Crossfeed (see Chu Moy's "An Acoustic Similator for H.Amps") Jan Meier's variations (Enhanced-Bass Natural crossfeed"), and also the Ohman system that I use (T.Kemhagens "Lindesberg Amp").
There are all sorts of amps and the Zen Amp (Marchello - a mini version of the Zen Amp) is a good simple design, plus the Szekeres and Murdey variations. Good fun!
My Mini F3 amp/ Ohman Xfeed/ Lightspeed Vol Control project still has a few buffer/gainstage problems - the F3 amp is ideal for 'phones, including the AKG 701 and Beyer 990s, and no fatigue at all!
A mini F4 would be a lot simpler - hmmmm!
I wonder if anybody is game enough to try the EnABL pattern to the h.phone's diaphrams?!!
Hope this is of assistance ... jh
Headphones do require more attention to detail than speakers, and when source, amp, cables, etc are "set-up" well, are more capable of superior reproduction.
However, the unnatural sound is not ideal but, as Dave and Protos have said, the Crossfeed tecnique has transformed the problem into an assett.
I'm still surprised that it's not a Universal option, particularly with some of the higher quality, IC based amps.
The Headwize site is the place for more info about Crossfeed systems including the original 1970's Linkwitz Crossfeed (see Chu Moy's "An Acoustic Similator for H.Amps") Jan Meier's variations (Enhanced-Bass Natural crossfeed"), and also the Ohman system that I use (T.Kemhagens "Lindesberg Amp").
There are all sorts of amps and the Zen Amp (Marchello - a mini version of the Zen Amp) is a good simple design, plus the Szekeres and Murdey variations. Good fun!
My Mini F3 amp/ Ohman Xfeed/ Lightspeed Vol Control project still has a few buffer/gainstage problems - the F3 amp is ideal for 'phones, including the AKG 701 and Beyer 990s, and no fatigue at all!
A mini F4 would be a lot simpler - hmmmm!
I wonder if anybody is game enough to try the EnABL pattern to the h.phone's diaphrams?!!
Hope this is of assistance ... jh
jameshillj said:
JH, thank you, very interesting news for me, new DIY areas, new terms - not all clear for me.
>>>X feed helps to sort out Capacitor differences<<<. Does it mean - when X feed is inserted between headphones and f4 – some C1/C2 capacitors move image more, some less out of head??? In other words does it look like legendary Black Gate N will generate the widest image in front of head? I will appreciate very much if try you describe your sense of hearing.
Best Regards,
a 😉
Please excuse this off subject discussion - not sure where to go! (and Yes, I have been told today!)
Sorry Andrzej for the confusion - it's nothing like that.
It's quite simply a HEADPHONES system for adding some delayed left channel info into the Right channel Headphones (and v.v.) to replicate the same mechanism of the speakers. Properly done, it results in outstanding performance, quite superior to good hifi speakers with good room acoustics.
Now, if you want to use the F4 amp to also listen to your headphones, then the addition of the Crossfeed Cct will definitely add to the headphone's stereo reproduction, BUT......
All the Xfeed filters have varying impedance with frequency and will require a buffer to avoid nonlinear (poor) F4 performance. It is possible to add the filters to the O/P of the F4, but only fair results.
"Xfeed helps to sort out Cap differences"
Sorry about this - all I meant is that it is far easier to sort out the different sounds of this amp with headphones, including when changing out capacitors and, as you have found, cct problems and other misbehaviour. (The Xfeed cct makes it easier to listen to the headphones, is all)
The different types of C1,2 of the F4 amp will simply tailor the basic sound of the amp a bit - Black Gates are my choice of sound with a lot of detail, accurate bass, etc, etc. Other folks like extra base weight of Nichicons, fatter mids of Cerafines, more balanced sound of Silmics, and so on. (There are many other good caps.)
Also, a lot of folks will disagree with my ideas of the different cap sounds described above - it's very individual. (N.B. IMO!)
Hope this helps.
Is there a place for H.P. discussion on DIY Audio?
Sorry Andrzej for the confusion - it's nothing like that.
It's quite simply a HEADPHONES system for adding some delayed left channel info into the Right channel Headphones (and v.v.) to replicate the same mechanism of the speakers. Properly done, it results in outstanding performance, quite superior to good hifi speakers with good room acoustics.
Now, if you want to use the F4 amp to also listen to your headphones, then the addition of the Crossfeed Cct will definitely add to the headphone's stereo reproduction, BUT......
All the Xfeed filters have varying impedance with frequency and will require a buffer to avoid nonlinear (poor) F4 performance. It is possible to add the filters to the O/P of the F4, but only fair results.
"Xfeed helps to sort out Cap differences"
Sorry about this - all I meant is that it is far easier to sort out the different sounds of this amp with headphones, including when changing out capacitors and, as you have found, cct problems and other misbehaviour. (The Xfeed cct makes it easier to listen to the headphones, is all)
The different types of C1,2 of the F4 amp will simply tailor the basic sound of the amp a bit - Black Gates are my choice of sound with a lot of detail, accurate bass, etc, etc. Other folks like extra base weight of Nichicons, fatter mids of Cerafines, more balanced sound of Silmics, and so on. (There are many other good caps.)
Also, a lot of folks will disagree with my ideas of the different cap sounds described above - it's very individual. (N.B. IMO!)
Hope this helps.
Is there a place for H.P. discussion on DIY Audio?
I have switched F4 production over to Elna "silk" capacitors,
as being the best electrolytics that we have measured and
listened to.
as being the best electrolytics that we have measured and
listened to.
?
Acronym Definition
PTL Praise The Lord
PTL Parent Teacher League
PTL Part-Time Lecturers
PTL Party To Loss (insurance)
PTL Paschell Truck Lines
PTL Pass The Loot
PTL Pass-Transistor Logic (lowering power consumption in digital circuits)
PTL Pay the Lady (National Thoroughbred Racing Association)
PTL Peak Traffic Load
PTL Pedro the Lion (band)
PTL Petroleum Testing Laboratory
PTL Pharnygotracheal Lumen (airway device)
PTL Photovoltaic Testing Laboratory (Arizona State University)
PTL Physikalisch Technische Lehranstalt (Wedel, Germany)
PTL Planar Transmission Line
PTL Platform Team Leader
PTL Pressure Treated Lumber
PTL Preterm Labor
PTL Primary Target Line
PTL Prime Transport Limited
PTL Prise de Terrain en L (aeronautics)
PTL Program/Project Team Leader
PTL Protecting the US Technical Lead
PTL ProTrader Language
PTL Pushing the Limits (gaming team)
Acronym Definition
PTL Praise The Lord
PTL Parent Teacher League
PTL Part-Time Lecturers
PTL Party To Loss (insurance)
PTL Paschell Truck Lines
PTL Pass The Loot
PTL Pass-Transistor Logic (lowering power consumption in digital circuits)
PTL Pay the Lady (National Thoroughbred Racing Association)
PTL Peak Traffic Load
PTL Pedro the Lion (band)
PTL Petroleum Testing Laboratory
PTL Pharnygotracheal Lumen (airway device)
PTL Photovoltaic Testing Laboratory (Arizona State University)
PTL Physikalisch Technische Lehranstalt (Wedel, Germany)
PTL Planar Transmission Line
PTL Platform Team Leader
PTL Pressure Treated Lumber
PTL Preterm Labor
PTL Primary Target Line
PTL Prime Transport Limited
PTL Prise de Terrain en L (aeronautics)
PTL Program/Project Team Leader
PTL Protecting the US Technical Lead
PTL ProTrader Language
PTL Pushing the Limits (gaming team)
Trim pots...
Are the trim pots both 5k?
One of the BOM's that was posted in the thread listed one of them as 500 ohms.
Just checking before I order...
Thanks,
C
Are the trim pots both 5k?
One of the BOM's that was posted in the thread listed one of them as 500 ohms.
Just checking before I order...
Thanks,
C
Nelson Pass said:
That is strong praise indeed!
Can anyone suggest a retail source for these capacitors?
Neither Michael Percy nor Partsconnexion seem to
carry them.
Thanks,
Dennis
Nelson Pass said:
Pass The Lord.
I'm suffering from a Rubycon BG allergy, tried those within months after they came on the market a long long time ago and still continue to be baffled by the (Star) Gate hysteria mystery.
Promoting a component that is yet affordable with data to back it up might reconnect some folks to "unlocking the mystery of life"
Dennis Hui said:
Try Handmade Electronics www.hndme.com/
I bought stuff from them before with great experience
Yes, but selection is rather limited presently: http://search.digikey.com/scripts/DkSearch/dksus.dll?lang=en&site=US&keywords=elna+rfs&x=0&y=0
GRollins said:
You're right! Somehow I had thought the part
is a 105C cap and didn't look far enough to
see that RFS=SILMIC II. Thank you very much.
Cheers,
Dennis