Stated as very efficient too and not folding like other SONY I see. 106dB/mW at 63Ω translates to 118dB/1V. Will be at 120dB SPL with only 25mW. Can you hear any hiss at max volume? I couldn't hear any with the very efficient Sennheiser HD8 DJ at least. But those are HF drooping. SONY are usually peaking somewhere in HF. Is it more expensive than the ubiquitous MDR-7506? Using a Japanese Muses kit with Nichicon Fine Gold caps on it and Japanese market exclusive meant headphones, you are surely treated into a dose of Japanese audio culture tone
I can't notice any hiss at high volume. It's deadly silent to my ear.
I bought the cans with around USD$ 200 equivalent. Some says that it is same as MDR-7506 and some says it's tweak for human voice for pop music recording. I don't have MDR-7506, so not able to tell the differences.
80VA if you mean one core with two center tapped 34V secondary sets for discrete outputs to double mono DCSTB plus a two wire low voltage set for Soekris feed.
(17-0-17 sets will save you some DCSTB sinks heat if it will be a custom order VS typical 18-0-18 off the shelf trafos. If for another alternative PSU type, order what secondary AC voltage values are best recommended for +/-17Vdc output by its designer)
(17-0-17 sets will save you some DCSTB sinks heat if it will be a custom order VS typical 18-0-18 off the shelf trafos. If for another alternative PSU type, order what secondary AC voltage values are best recommended for +/-17Vdc output by its designer)
It is time to report about my second round of BC327-40 swap on the same first unit. I flowed friend's advice and purchased 100 pieces from eBay Germany. They are made by Diotec. Very consistent batch for matching purposes, but all are in 380-390 range for Hfe. Vbe is also very tight and all are in range of 0.752-0.755V. I got only 4 pieces with 400-402 Hfe and same tight Vbe. Exactly these I used that time. Also, I installed headers for easy future swap (if needed), as Salas advised. After minor adjustment for DC offset post 20-30 min of warm up, I started audition test.
Connected my Monolith M1060 set and I was so disappointed since I got harsh, extremely distorted and noisy sound. I was so upset that I took a brake and let it to run. I got back after 10 min and unit sounded amazingly well. First assumption was related to warm up or burn-in of these 327s.Then, I moved a bit and got same distortion again. It was my Monolith 1/4" plug adapter that transiently failed. Bad connection caused that issue. Very low quality piece (already in trash) and guys who use same headphones might need to consider buying better adapter.
I have same plosive feedback as with Fairchild set witch I had with bit lower Hfe. Nice and crystal clear sound. For me, it is the way to go and I'm not looking back to 560s. The hard part is to find high Hfe pieces values of 500 or higher. I got no luck, so far. If some of you already have an extra of these with high Hfe , measured by Atlas or equivalent, and willing to sale, then I'm in. Please PM me. Personal appreciation to Salas.
Connected my Monolith M1060 set and I was so disappointed since I got harsh, extremely distorted and noisy sound. I was so upset that I took a brake and let it to run. I got back after 10 min and unit sounded amazingly well. First assumption was related to warm up or burn-in of these 327s.Then, I moved a bit and got same distortion again. It was my Monolith 1/4" plug adapter that transiently failed. Bad connection caused that issue. Very low quality piece (already in trash) and guys who use same headphones might need to consider buying better adapter.
I have same plosive feedback as with Fairchild set witch I had with bit lower Hfe. Nice and crystal clear sound. For me, it is the way to go and I'm not looking back to 560s. The hard part is to find high Hfe pieces values of 500 or higher. I got no luck, so far. If some of you already have an extra of these with high Hfe , measured by Atlas or equivalent, and willing to sale, then I'm in. Please PM me. Personal appreciation to Salas.
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Now with the new Audeze LCD2C version at $800 more people will likely go for the genuine article avoiding cheap materials & workmanship incidents with otherwise good sounding clones.
At same Hfe the 327s performed as good as the American brand's units then. Logical outcome. Although it was nice they proved tighter for more matches in a batch. My old batch was loose for matching but had enough high hitters. Each process is what each process is...
At same Hfe the 327s performed as good as the American brand's units then. Logical outcome. Although it was nice they proved tighter for more matches in a batch. My old batch was loose for matching but had enough high hitters. Each process is what each process is...
DCG3. Great headphones amplifier.
After using the dcg3 as a preamplifier with a diy F5 Turbo for a while I decided to upgrade my headphones from Grados SR80's to something better. I stay listening to music late in the day when doing business chores I did not want to disturb the wife and kid with music that could be loud for the time of the day. Last week I received the new Fostex HP's.
The preamp was built with high bias, 140 mA I believe, well the combo sound is excellent to my ears. I'm very satisfied with the result. The dgc3 has no issues driving the low impedance of the HP's. I played the music through the headphones and amplifier simultaneously to compare them (is this bad? Too big of a load for the preamp?)
The bad part is that I've been spoiled and the sound of music through the F5 and speakers does not sound as good as I perceived it before I got the HP's. It is still very good though.
This weekend the dcg3 gets its final case. It began it's life as an experiment, since it has gained a place in my audio system.
Thanks Salas and fellow diy'ers! Life is better with good music!
After using the dcg3 as a preamplifier with a diy F5 Turbo for a while I decided to upgrade my headphones from Grados SR80's to something better. I stay listening to music late in the day when doing business chores I did not want to disturb the wife and kid with music that could be loud for the time of the day. Last week I received the new Fostex HP's.
The preamp was built with high bias, 140 mA I believe, well the combo sound is excellent to my ears. I'm very satisfied with the result. The dgc3 has no issues driving the low impedance of the HP's. I played the music through the headphones and amplifier simultaneously to compare them (is this bad? Too big of a load for the preamp?)
The bad part is that I've been spoiled and the sound of music through the F5 and speakers does not sound as good as I perceived it before I got the HP's. It is still very good though.
This weekend the dcg3 gets its final case. It began it's life as an experiment, since it has gained a place in my audio system.
Thanks Salas and fellow diy'ers! Life is better with good music!
Salas, what was the average hfe value of the 327 Diotecs you put in vs the 560's you had in there previously?
You mentioned previously that you could turn up the volume 1 notch higher. Not sure what you mean.
If replacing the mirror Q1 Q2 with devices with lower hfe wont the final system gain also be reduced? Any approximation?
Thanks. nash
Thanks, it does. I did a good job matching the input jfets. These are lsk170/lsj74. I'm not going to move that put until I get my hands on a audio analyzer or PC based software/audio interface to be sure of what I'm doing with it. I'm still in the learning process. The F5 Turbo sounds terrific, don't get my wrong. It actually a bit warmer than the headphones but there in more information through the headphones. Two different presentations both are satisfying.
Had two pairs of about Hfe 510 Fairchild BC560s and I managed to replace with two pairs of nearly as much Hfe Diotec 327-40s.
If replacing with say Hfe 350 the mirror's active loading for the input stage's JFETs will lessen so the total internal gain (open loop gain or OLG) will lessen also. Thus somewhat less feedback will be available to the circuit's use. About 8% less. The closed loop gain (what you actually set and use) will not change at all.
We were simply trying to set the football field absolutely even for 560s and 327s to compete but it can simply be about worrying too much because the DCG3's internal gain is enormous anyway and it can afford to spare a little.
With able to listen at one notch higher on the pot I meant that the system's sound had to go higher up a notch than before to meet my personal limit for becoming offensive. Not a real voltage gain difference, a tonality/naturalness subjective difference.
Typical room's modes and reverberation blurring won't allow as much detail to cut through from your speakers to your sofa as from your new top dollar phase coherent Fostex diaphragm an inch away to your ear. They spend a ton on excellent big active monitor systems, room design, surface treatment, trap, diffuse, and DSP alignment, in high class commercial studios toward that difficult goal.
The burden of simultaneous amp replay is peanuts vs a headphone's load alone, no worries. Life's better with good music indeed and do enjoy it. You are welcome. Regards.
Your are welcome. Now you know what my real motive was. To can take it up a notch to... eleven
Eleven Is One Louder - Spinal Tap
Thanks Salas. That is exactly the type of judgment that I'm not able to make for lack of knowledge!
It keeps expectations real.
This is a follow up review of several of the DIY headphone amps presented in the past months through several brands of headphones.
My original post on the Salas DCG3 build is #2131, for the XRK971 build is #1229 and the Pass DIY build is #820 for anyone wanting to read my first thoughts.
Since that posting, I have purchased through a MassDrop buy, a set of Sennheiser HD6XX phones, which I believe are actually HD650 cans. New additions on the headphone amp side include one of Pete Millet's Korg Nutube headphone amps and a desktop (AC) version of XRK971 PCA. This amp is biased at 120ma, running larger Panasonic caps on the output and very large caps (15000uf) on the power input than a battery operated version of the PCA. The Nutube amp also has a pair of Burson V6i opamps in place of the recommended OPA551 opamps. The Pass DIY by Wayne has a Sparkoslab SS3602 in place of the AD823.
Play back is now through a SMSL M8A DAC with a clean outboard 5vdc supply. Also inline is an Uptone USB Regen. The audio file is a .FLAC. All systems are given a minimum of 24hrs at room temperature before listening.
Last time I used a live performance of Dave Brubeck's "Take Five". This time I am using a Pink Floyd song from their 1973 album "Dark Side of the Moon". That song is " The Great Gig in the Sky". The instruments are a piano, Hammond organ, pedal steel guitar, bass, and drums. The main vocals are supplied in an almost orgasmic way by Clare Torry. Her wailing reveals much about the amps and headphones!!
Salas DCG3
Sennheiser HD6XX
Wide soundstage with drums and Torry appear in the center. Cymbals are clear and crisp sounding. Organ far left, piano front in right ear. Vocals soar with no obvious distortion. The piano is well defined.
HiFi 400i
Similar wide stage as the Sennheiser cans, spoken voice clear. The cymbals and Torry's vocals are not as clear as with the Sennheiser phones. Bass is very defined. For the second set of vocals Torry is slightly overpowered by the piano. Piano and bass are clearly defined.
Thinkd Sound ON-2
Soundstage appears lower and more separated. Cymbals are clear and defined. Vocals are centered and also well defined. Drums and cymbals crisp sounding. There is a better balance with the piano and Torry. Piano crisp with nice overtones.
OB1
Nice base definition. Good soundstage, though drums and cymbals are masked somewhat by the organ and piano. Torry vocals are a bit muddy sounding. In her second set of vocals the sound is more subdued as well the piano is less defined. Overall a more muted sound not as defined, though not unpleasant to listen to.
Ultrasone Pro 750
Piano sounds slightly smeared with a bright sound. Drums and cymbals have very clear sizzle to their sound. Hammond organ very dominate in left ear. Torry's 2nd vocals are clean sounding the piano sound is rounded, with the bass somewhat subdued.
Sony 7506
Piano is thin sounding, with the bass rounded and full sounding. Drums and cymbals are prominent and defined. Torry's vocals are the most upfront sounding of the headphones I have. In her 2nd set of vocals the bass is very dominate with the piano still sounding thin, not as defined.
Audio Technica ATH-M50
A very detailed piano, with good bass, nice wide soundstage. The drums are distinct with the cymbals having a clear sizzle to their sound. Torry's vocals clearly defined. The Hammond organ has a nice mellow sound. Torry's 2nd vocals are still defined and the bass is very present. However she appears to sound more in the background with the bass and piano up front.
XKR971 desktop Pocket Headphone Amp
Ultrasone Pro 750
Piano smeared somewhat, not as distinct. Drums are clear and the cymbals have a nice sizzle sound to them. Hammond organ sounds muddy, not as clear. Torry's vocals are bright. In the 2nd part the piano is still a bit muddy sounding, though there is a nice balance with vocals, piano and bass.
Audio Technica ATH-M50
Piano clean sounding with a wide soundstage. Hammond organ is distinct. Drums and bass are more pronounced. The vocals are not as clear and defined.
Sony 7506
Vocal very clear. Pedal steel and organ are clean and clear sounding. Drum and cymbals are well defined. The bass is very pronounced. In 2nd set Torry's vocals are a bit shrill sounding, but clear. Individual piano notes are clear. For this amp and song this headphones really are nice.
HiFi 400i
Wide soundstage with a clear organ and piano. Nice airy vocals with the drums and cymbals crisp. Hammond organ is distinct with a good balance on vocals and rest of the instruments. Torry's 2nd vocals really soar and the piano is nice and round with distinct overtones.
OB1
Wide soundstage with defined bass and clear pedal steel. A good blend of organ, drums, vocals and piano. Smooth clear 2nd vocals and piano. There is a nice balance with good depth in the soundstage.
Think Sound ON2
Slightly bright piano. The pedal steel sound smooth, with nice drums and cymbals sizzle. The organ is clean and defined. The bass is very solid along with clean, clear vocals. Torry's 2nd vocals and overall sound are nicely balanced. The piano and bass are balanced with the piano not as bright. Her vocals are very light and smooth.
Sennheiser HD6XX
Piano very natural sounding, with the pedal steel smooth and rounded. A wide soundstage with the drums somewhat muted and cymbals not as crisp sounding. The vocals are further in the background. Her 2nd vocals are distinct and soaring. The piano is very nice with the bass sounding further back, not as dominate. Overall a good balance.
Pete Millet Korg headphone amp.
HiFi 400i
Nice wide soundstage with a natural sounding piano. Clear pedal steel and crisp sounding drums and cymbals. The Hammond organ is nice and distinct, with Torry's vocals being more centered and clear. In the 2nd there is a good balance between the vocal, piano, and bass. Torry's voice seems to float above it all.
Audio Technica ATH-M50
Good bass with a wide soundstage. Pedal steel is not as distinct. The drums are more forward, additionally the organ and drums seem to overpower the vocals a bit. Her second vocals are better sounding balance with the instruments. They also are brighter and pushed back in the soundstage. The bass is very prominent.
Sennheiser HD6XX
Another wide soundstage with the pedal steel and vocals clear. The Hammond organ is distinct. Drums have a nice balance with the crisp cymbals coming through. Overall good balance between the vocal and instruments. Torry's vocals just seem to float and soar in this 2nd bit, with the piano notes clear and distinct. The bass appears at a slightly lower level.
Sony 7506
Defined piano and bass on a wide soundstage. The pedal steel is distinct with the drums sounding upfront, though a bit over powering. Torry's vocals are clear and distinct as is the Hammond organ. In the second part she is heard a bit more forward in depth and every bit as clear. Piano and bass are well defined.
Think Sound ON2
Rounded bass and pedal steel with the piano not as defined. A nice wide soundstage. The Hammond organ and vocals are defined. The cymbal really has nice sizzle and the drums are very forward. Torry's vocals in the second part seem pushed back, but still distinct. The piano and bass dominate in this section.
OB-1
A wide soundstage, with a forward sounding piano. Pedal steel not as distinct, with the overall sound not as defined. The organ, drums, piano are blending together more. Vocal is also muddy sounding. Same for the 2nd bit, vocals sound muted, with the piano not as defined. However the balance of the piano, bass and vocals is ok.
Ultrasone Pro750
Another wide soundstage. Overall a bit light sounding, not in your face. The pedal steel and Hammond organ are clear and defined. Piano though sounds muddy. The cymbals sound almost a bit artificial sounding. Torry's vocals are clear. The bass and piano have a nice balance in this second bit with her vocals centered though a little muddy sounding.
Wayne's Pass Headphone Amp
Audio Technica ATH-M50
Wide soundstage, with a clear pedal steel and full sounding bass. Upfront Hammond organ, with distinct drum and cymbal sounds. Vocals appear pushed back, but very distinct sounding. In the second bit, piano and vocals have a nice balance and still are clear and distinct. The bass seems a bit upfront.
Sony 7506
Piano and pedal steel are distinct and clear. Vocals are more forward and clear. Same with Hammond organ and piano. The bass is dominate. For the 2nd bit vocals are airy and distinct with a nice balance against the piano. Bass is at an even level, not too forward.
HiFi 400i
Piano, bass, and pedal steel are distinct on a nice wide soundstage, with a nice balance. The cymbals are a bit down and sound slightly muted. The vocals and Hammond organ not as clear. In the second, Torry's vocals seem a bit smeared sounding and not as bright. The piano and bass are nice sounding with good imaging. The vocals sound more forward.
Think Sound ON-2
Nice balance on the piano and pedal steel. The organ and Torry's vocals are distinct and a bit more forward. Drums and cymbals have a clear sound with nice sizzle. In the second bit, the bass, piano and vocals still maintain a nice balance, plus the vocal are still distinct. The bass is not as dominate. Overall a very smooth rounded sound.
OB-1
Piano, pedal steel and bass are nicely balanced on a wide soundstage. Cymbals are crisp and distinct. Vocals are not as clear, with the bass and Hammond organ dominate. For the 2nd bit the bass still dominates, the piano is distinct. The vocals have some smear but are more forwad in the soundstage.
Sennheiser HD6XX
Needs more drive from this headphone amp. Bass not so forward, with the pedal steel and piano nice and rounded. The drums and vocals seem a bit pushed back, with the cymbals sounding very natural. The organ is clear and distinct. Nice overtones in the second bit with Torry's vocals more prominent. Piano and bass have a nice balance.
Ultrasone Pro 750
A wide soundstage, with the cymbals lacking some sizzle. Organ and vocals sound slightly muddy. For the second part the piano and Torry's vocals are distinct. Both appear centered in the soundstage with the piano slightly more forward. The bass is nicely matched with the piano and vocals.
This posting is just one person's thoughts on how some of the DIY headphone amps and various headphones sound. Your listening results will certainly differ from mine.
For me it is a lot about the build and then the enjoyment of listening to something I have built. Thanks to the many out there that can design these amps and are willing to share with the rest of us.
David
My original post on the Salas DCG3 build is #2131, for the XRK971 build is #1229 and the Pass DIY build is #820 for anyone wanting to read my first thoughts.
Since that posting, I have purchased through a MassDrop buy, a set of Sennheiser HD6XX phones, which I believe are actually HD650 cans. New additions on the headphone amp side include one of Pete Millet's Korg Nutube headphone amps and a desktop (AC) version of XRK971 PCA. This amp is biased at 120ma, running larger Panasonic caps on the output and very large caps (15000uf) on the power input than a battery operated version of the PCA. The Nutube amp also has a pair of Burson V6i opamps in place of the recommended OPA551 opamps. The Pass DIY by Wayne has a Sparkoslab SS3602 in place of the AD823.
Play back is now through a SMSL M8A DAC with a clean outboard 5vdc supply. Also inline is an Uptone USB Regen. The audio file is a .FLAC. All systems are given a minimum of 24hrs at room temperature before listening.
Last time I used a live performance of Dave Brubeck's "Take Five". This time I am using a Pink Floyd song from their 1973 album "Dark Side of the Moon". That song is " The Great Gig in the Sky". The instruments are a piano, Hammond organ, pedal steel guitar, bass, and drums. The main vocals are supplied in an almost orgasmic way by Clare Torry. Her wailing reveals much about the amps and headphones!!
Salas DCG3
Sennheiser HD6XX
Wide soundstage with drums and Torry appear in the center. Cymbals are clear and crisp sounding. Organ far left, piano front in right ear. Vocals soar with no obvious distortion. The piano is well defined.
HiFi 400i
Similar wide stage as the Sennheiser cans, spoken voice clear. The cymbals and Torry's vocals are not as clear as with the Sennheiser phones. Bass is very defined. For the second set of vocals Torry is slightly overpowered by the piano. Piano and bass are clearly defined.
Thinkd Sound ON-2
Soundstage appears lower and more separated. Cymbals are clear and defined. Vocals are centered and also well defined. Drums and cymbals crisp sounding. There is a better balance with the piano and Torry. Piano crisp with nice overtones.
OB1
Nice base definition. Good soundstage, though drums and cymbals are masked somewhat by the organ and piano. Torry vocals are a bit muddy sounding. In her second set of vocals the sound is more subdued as well the piano is less defined. Overall a more muted sound not as defined, though not unpleasant to listen to.
Ultrasone Pro 750
Piano sounds slightly smeared with a bright sound. Drums and cymbals have very clear sizzle to their sound. Hammond organ very dominate in left ear. Torry's 2nd vocals are clean sounding the piano sound is rounded, with the bass somewhat subdued.
Sony 7506
Piano is thin sounding, with the bass rounded and full sounding. Drums and cymbals are prominent and defined. Torry's vocals are the most upfront sounding of the headphones I have. In her 2nd set of vocals the bass is very dominate with the piano still sounding thin, not as defined.
Audio Technica ATH-M50
A very detailed piano, with good bass, nice wide soundstage. The drums are distinct with the cymbals having a clear sizzle to their sound. Torry's vocals clearly defined. The Hammond organ has a nice mellow sound. Torry's 2nd vocals are still defined and the bass is very present. However she appears to sound more in the background with the bass and piano up front.
XKR971 desktop Pocket Headphone Amp
Ultrasone Pro 750
Piano smeared somewhat, not as distinct. Drums are clear and the cymbals have a nice sizzle sound to them. Hammond organ sounds muddy, not as clear. Torry's vocals are bright. In the 2nd part the piano is still a bit muddy sounding, though there is a nice balance with vocals, piano and bass.
Audio Technica ATH-M50
Piano clean sounding with a wide soundstage. Hammond organ is distinct. Drums and bass are more pronounced. The vocals are not as clear and defined.
Sony 7506
Vocal very clear. Pedal steel and organ are clean and clear sounding. Drum and cymbals are well defined. The bass is very pronounced. In 2nd set Torry's vocals are a bit shrill sounding, but clear. Individual piano notes are clear. For this amp and song this headphones really are nice.
HiFi 400i
Wide soundstage with a clear organ and piano. Nice airy vocals with the drums and cymbals crisp. Hammond organ is distinct with a good balance on vocals and rest of the instruments. Torry's 2nd vocals really soar and the piano is nice and round with distinct overtones.
OB1
Wide soundstage with defined bass and clear pedal steel. A good blend of organ, drums, vocals and piano. Smooth clear 2nd vocals and piano. There is a nice balance with good depth in the soundstage.
Think Sound ON2
Slightly bright piano. The pedal steel sound smooth, with nice drums and cymbals sizzle. The organ is clean and defined. The bass is very solid along with clean, clear vocals. Torry's 2nd vocals and overall sound are nicely balanced. The piano and bass are balanced with the piano not as bright. Her vocals are very light and smooth.
Sennheiser HD6XX
Piano very natural sounding, with the pedal steel smooth and rounded. A wide soundstage with the drums somewhat muted and cymbals not as crisp sounding. The vocals are further in the background. Her 2nd vocals are distinct and soaring. The piano is very nice with the bass sounding further back, not as dominate. Overall a good balance.
Pete Millet Korg headphone amp.
HiFi 400i
Nice wide soundstage with a natural sounding piano. Clear pedal steel and crisp sounding drums and cymbals. The Hammond organ is nice and distinct, with Torry's vocals being more centered and clear. In the 2nd there is a good balance between the vocal, piano, and bass. Torry's voice seems to float above it all.
Audio Technica ATH-M50
Good bass with a wide soundstage. Pedal steel is not as distinct. The drums are more forward, additionally the organ and drums seem to overpower the vocals a bit. Her second vocals are better sounding balance with the instruments. They also are brighter and pushed back in the soundstage. The bass is very prominent.
Sennheiser HD6XX
Another wide soundstage with the pedal steel and vocals clear. The Hammond organ is distinct. Drums have a nice balance with the crisp cymbals coming through. Overall good balance between the vocal and instruments. Torry's vocals just seem to float and soar in this 2nd bit, with the piano notes clear and distinct. The bass appears at a slightly lower level.
Sony 7506
Defined piano and bass on a wide soundstage. The pedal steel is distinct with the drums sounding upfront, though a bit over powering. Torry's vocals are clear and distinct as is the Hammond organ. In the second part she is heard a bit more forward in depth and every bit as clear. Piano and bass are well defined.
Think Sound ON2
Rounded bass and pedal steel with the piano not as defined. A nice wide soundstage. The Hammond organ and vocals are defined. The cymbal really has nice sizzle and the drums are very forward. Torry's vocals in the second part seem pushed back, but still distinct. The piano and bass dominate in this section.
OB-1
A wide soundstage, with a forward sounding piano. Pedal steel not as distinct, with the overall sound not as defined. The organ, drums, piano are blending together more. Vocal is also muddy sounding. Same for the 2nd bit, vocals sound muted, with the piano not as defined. However the balance of the piano, bass and vocals is ok.
Ultrasone Pro750
Another wide soundstage. Overall a bit light sounding, not in your face. The pedal steel and Hammond organ are clear and defined. Piano though sounds muddy. The cymbals sound almost a bit artificial sounding. Torry's vocals are clear. The bass and piano have a nice balance in this second bit with her vocals centered though a little muddy sounding.
Wayne's Pass Headphone Amp
Audio Technica ATH-M50
Wide soundstage, with a clear pedal steel and full sounding bass. Upfront Hammond organ, with distinct drum and cymbal sounds. Vocals appear pushed back, but very distinct sounding. In the second bit, piano and vocals have a nice balance and still are clear and distinct. The bass seems a bit upfront.
Sony 7506
Piano and pedal steel are distinct and clear. Vocals are more forward and clear. Same with Hammond organ and piano. The bass is dominate. For the 2nd bit vocals are airy and distinct with a nice balance against the piano. Bass is at an even level, not too forward.
HiFi 400i
Piano, bass, and pedal steel are distinct on a nice wide soundstage, with a nice balance. The cymbals are a bit down and sound slightly muted. The vocals and Hammond organ not as clear. In the second, Torry's vocals seem a bit smeared sounding and not as bright. The piano and bass are nice sounding with good imaging. The vocals sound more forward.
Think Sound ON-2
Nice balance on the piano and pedal steel. The organ and Torry's vocals are distinct and a bit more forward. Drums and cymbals have a clear sound with nice sizzle. In the second bit, the bass, piano and vocals still maintain a nice balance, plus the vocal are still distinct. The bass is not as dominate. Overall a very smooth rounded sound.
OB-1
Piano, pedal steel and bass are nicely balanced on a wide soundstage. Cymbals are crisp and distinct. Vocals are not as clear, with the bass and Hammond organ dominate. For the 2nd bit the bass still dominates, the piano is distinct. The vocals have some smear but are more forwad in the soundstage.
Sennheiser HD6XX
Needs more drive from this headphone amp. Bass not so forward, with the pedal steel and piano nice and rounded. The drums and vocals seem a bit pushed back, with the cymbals sounding very natural. The organ is clear and distinct. Nice overtones in the second bit with Torry's vocals more prominent. Piano and bass have a nice balance.
Ultrasone Pro 750
A wide soundstage, with the cymbals lacking some sizzle. Organ and vocals sound slightly muddy. For the second part the piano and Torry's vocals are distinct. Both appear centered in the soundstage with the piano slightly more forward. The bass is nicely matched with the piano and vocals.
This posting is just one person's thoughts on how some of the DIY headphone amps and various headphones sound. Your listening results will certainly differ from mine.
For me it is a lot about the build and then the enjoyment of listening to something I have built. Thanks to the many out there that can design these amps and are willing to share with the rest of us.
David
Hello David
Very nice extensive and thorough notes. You should check the DCG3 with BC327-40 Q1 Q2 alternative transistors too. Since you got details on various cans and this amp among others so you can look back into them, you would be a more systematic man in approach to tell us your opinion too for subjective details between the original BC560C type you got and listened with VS the BC327-40 alternative type. 0.1 inch pitch female header pins in triplets cut from a row would help you go back and forth even. Refresh the offset procedure as described in the build manual after installing the new type. In the end you keep what transistors you preferred overall even without reworking the board to solder them back. Their pins to headers mechanical connection is very good, as good as the servo op-amp's in its socket.
Very nice extensive and thorough notes. You should check the DCG3 with BC327-40 Q1 Q2 alternative transistors too. Since you got details on various cans and this amp among others so you can look back into them, you would be a more systematic man in approach to tell us your opinion too for subjective details between the original BC560C type you got and listened with VS the BC327-40 alternative type. 0.1 inch pitch female header pins in triplets cut from a row would help you go back and forth even. Refresh the offset procedure as described in the build manual after installing the new type. In the end you keep what transistors you preferred overall even without reworking the board to solder them back. Their pins to headers mechanical connection is very good, as good as the servo op-amp's in its socket.
Attachments
I'm using older NHT 2.9's a 4 way design. The front of the speakers is angled towards the listening position. The woofers are mounted low on the inside side of the cabinets. They are 3 meters apart with their back 6 inches from the rear wall. My listening position is 4.5 meters in front of them. The flooring is carpeting, ceilings and walls are dry wall covering how wall framing.
I'm happy with the sound, I don't listen to a lot of Rock, mostly jazz, lots of vocals, piano. Some classical, lots of afro-latin music.