[Rick_B]

BTW, I had to comment on your profile pic... I always loved those TR4's, as a matter of fact I shall be seeing some today, I'm on my way to a classic car show later!

As a side note I had the same experience as you with mail from Hong Kong, got here quicker than local mail!

I restored that 1962 TR4 from a basket case in the late seventies...I even drove it to a local transportation museum and it earned me a spot as their restoration manager...biggest mistake I made was selling that car, my 1967 390GT Mustang fastback, and my 1976 KZ-900...ahh well, the adventures of youth!

I miss British cars, they were so much fun to work on, and contrary to many beliefs, were not that bad as daily drivers....I had the TR4, a Spitfire, and restored also a Sprite and a Midget....I loved peeling my 6'3" self out of a Spridget....tiny little cars but I could fit in them, unlike the Honda S2000 or even the Miata of recent vintage.

Back to the subject of this thread, I'm impressed by the sound of this little amp...I've recently been using my Antique Sound Labs amp in transformer output mode with my HE-400i's...my impressions of this amp, with the coin base Sylvanias and a "real" NOS TungSol 12AX7 are very favorable, I need to do more evaluation and let the unit run in for a while before I do any real in depth analysis, but so far it is impressive.

I've been messing with electronics for over five decades, building, fixing, restoring, and using all kinds of audio and Ham Radio gear, doing a simple capacitor swap on this amp should be a doddle...with as good as it sounds stock, though, I wonder....

I've got a series of burn-in tracks running through the amp now and in a couple of days will listen more intently to see what the results tell me.

Thanks for the note!

 

[baronbeehive]

I miss British cars, they were so much fun to work on, and contrary to many beliefs, were not that bad as daily drivers....I had the TR4, a Spitfire, and restored also a Sprite and a Midget....I loved peeling my 6'3" self out of a Spridget....tiny little cars but I could fit in them, unlike the Honda S2000 or even the Miata of recent vintage.
….
I've been messing with electronics for over five decades, building, fixing, restoring, and using all kinds of audio and Ham Radio gear, doing a simple capacitor swap on this amp should be a doddle...with as good as it sounds stock, though, I wonder....

Thanks for the note!

OK, I was interested!

Must resist commenting on your various cars, some of which I know quite well! I know what you mean about fitting in cars, I have a new version Mini Cooper S (BMW) and I believe it has less room inside than the old minis, which I also had way back, which look like toys side by side with the new ones, this is down to all the safety features needed nowadays.

Yes the amp is good in stock form.... with the mods, and the right tubes, it is simply great! The amp is easy to mod, only problem the PC is not very sturdy so...!!

NB: there were 4 TR4's at the show today, all looking great!

 

[Maxx134]

I bought a box full of those Black Gates several years ago, still have a bunch...

If you have bigger than 330uf, try it.
I had tried similar size and was surprised how much more forcefull the bass achieved with 1000uf.
Even 2200uf is good as long as you add a .1uf or smaller film cap to help it..

 

[Rick_B]

If you have bigger than 330uf, try it.
I had tried similar size and was surprised how much more forcefull the bass achieved with 1000uf.
Even 2200uf is good as long as you add a .1uf or smaller film cap to help it..

More bass?

I just listened to Cryogenic Encounters by Liquid Stranger...I don't see the need for any more force in the bass than that...the well recorded high res FLACs, DSF, and WAV files stored on my computers are shown pretty darn well, the one area I am trying to improve is the "tinkly" stuff...for instance, I know how good Melody Gardot's "Who will comfort me" sounds on a $100K+ system I work with at least three times a week...I listen to the sound of the zills in a tambourine for instance, to tell me how clear and clean the high end is...I find that with my hearing that the less distortion there is in the high end the longer and more comfortably I can listen without fatigue and exacerbating my tinnitus...

Sometimes it is hard balancing getting the top end to be really good and natural sounding and not removing texture...I love texture...to me it's what makes music come alive.

I do have some Sprague 1000uf @ 63V caps, but does quality outweigh quantity here? That is, do the qualities of the Black Gate caps trump the higher microfarads of the Spragues?

 

[baronbeehive]

More bass?

I just listened to Cryogenic Encounters by Liquid Stranger...I don't see the need for any more force in the bass than that...the well recorded high res FLACs, DSF, and WAV files stored on my computers are shown pretty darn well, the one area I am trying to improve is the "tinkly" stuff...for instance, I know how good Melody Gardot's "Who will comfort me" sounds on a $100K+ system I work with at least three times a week...I listen to the sound of the zills in a tambourine for instance, to tell me how clear and clean the high end is...I find that with my hearing that the less distortion there is in the high end the longer and more comfortably I can listen without fatigue and exacerbating my tinnitus...

Sometimes it is hard balancing getting the top end to be really good and natural sounding and not removing texture...I love texture...to me it's what makes music come alive.

I do have some Sprague 1000uf @ 63V caps, but does quality outweigh quantity here? That is, do the qualities of the Black Gate caps trump the higher microfarads of the Spragues?

I'd like to chime in here, before Maxx134 adds his thing, because this is quite close to my heart, as I've been mentioning this very thing on the thread relating to the other amp I have, (the LD).

I entirely agree with you about the textural details, I first noticed them on this amp immediately after modding it, it came as quite a shock! Since then I've been trying to get the same sound from the other amp.

First, I think you need the bass frequencies to add richness to the sound throughout the frequencie response so that you don't get that annoying tinkly stuff you mention. I would choose the coupling caps with care as the most important change. I used Jupiter copper foil paper and wax caps mainly because I had one left over from modding the other amp. They have a great natural sound which we found out about on the other thread, however they are expensive. There are alternatives almost as good such as the ones Maxx134 used, Audyn True Copper, much cheaper. The important thing seems to be the copper which gives the lively realistic sound. The other thing is that the better quality caps separate the sound into layers better and bring air into the sound allowing you to hear what's going on more easily. They are also refined, but at the same time reveal all the detail that's there.

The cathode caps mainly allow efficient response from peaks in the waveform, so you get better speed and recovery as you probably know, so that the PSU is freed of some work in maintaining the signal waveform, important in a low output amp.

I spent a lot of time trying to remove the tinkly stuff from the other amp and then I realized it was just too smooth and needed texture back in the sound, for me this APPJ is one alive amp, it has this and it has clarity.

Bear in mind this is one of the cheapest amps on the market, but my amp, the speaker APPJ, has been said to be ridiculously good in expensive systems and I've been saying it for some time now, I wouldn't change a thing. Whether it will compete with a 10k system is another thing, something I wouldn't know about, but I have a feeling it would give it a good run for its money!

 

[Maxx134]

Sometimes it is hard balancing getting the top end to be really good and natural sounding and not removing texture...I love texture...to me it's what makes music come alive.

For texture, you will need above average coupling caps (Jupiter copper)...

I do have some Sprague 1000uf @ 63V caps, but does quality outweigh quantity here? That is, do the qualities of the Black Gate caps trump the higher microfarads of the Spragues?

My usage of the higher capacitance was for using demanding planar headphones, which can cause slight voltage fluctuations at the cathode resistor voltage.
The audible effect of larger size was actually more sustain , not greater bass.
In your case the blackgates would probably be preferable.

about on the other thread, however they are expensive. There are alternatives almost as good such as the ones Maxx134 used, Audyn True Copper, much cheaper.

I no longer recommend the Audyn for the "coupling" position.
Instead I would use it for a bypass position.
Although it was superior transparency, it also does not do as well, a layered soundstage.
I will be switching to Jupiter for coupling, and clarity cap CMR for any bypassing.
For the electrolytics, the Nichion Muse is also good like the AudioNote Kaisie.

And way cheaper.

 

[baronbeehive]

I know how good Melody Gardot's "Who will comfort me" sounds on a $100K+ system I work with at least three times a week

I wonder if you could hook up your APPJ to your 100k system somehow? Would be interesting.... I've already said that reviews have said how good my speaker APPJ is with high end speakers.

 

[Rick_B]

I wonder if you could hook up your APPJ to your 100k system somehow? Would be interesting.... I've already said that reviews have said how good my speaker APPJ is with high end speakers.

It's not my system, let's make that perfectly clear! I'm retired and live off of Social Security, there's no way I can afford something like that...even contemplating the price of the Jupiter capacitors mentioned in this thread is out of my budget...but, I do set-up and evaluate systems for people who do have the money, but not the time or expertise to do it well. I work part time for a well respected mail order/Internet audio dealer but have also been interested in electronics since building my first radio receiver over fifty years ago, I am nearing my fourth decade as an Advanced Class Ham Radio licensee yet high fidelity has been a passion of mine for decades.

My APPJ is a headphone amp, not a speaker amp, and the only thing I could do would be to hook it up to the Esoteric stack (transport, DAC, Rubidium Clock) and see how it performs there...I'm almost afraid to do that...it might melt my mind...

Getting to work around the upper echelon of audio gear really gives me a chance to "calibrate" my ears as to what is possible and helps guide my much more budgetary attempts to get good sound in my home.

I could take home, and have taken home, many, many pieces of gear over the past three decades to test and evaluate and therefore I realize that it is just my luck that allows me to sit and listen to it and get a handle on what is possible without having to "invest" a bunch of money in the gear.

Which is what has brought me to inexpensive headphone amps, I'm still trying to come up with something that does as well as the Bryston headphone amp that we carry, but for a lot less money...and, I have a lot of vacuum tubes in storage...

I still haven't done any mods to my APPJ, I prefer to let new electronics run in for two weeks with music and burn-in tracks before really sitting down to take a listen...

Thanks for the comments!

 

[Mecii]

For texture, you will need above average coupling caps (Jupiter copper)...


My usage of the higher capacitance was for using demanding planar headphones, which can cause slight voltage fluctuations at the cathode resistor voltage.
The audible effect of larger size was actually more sustain , not greater bass.
In your case the blackgates would probably be preferable.


I no longer recommend the Audyn for the "coupling" position.
Instead I would use it for a bypass position.
Although it was superior transparency, it also does not do as well, a layered soundstage.
I will be switching to Jupiter for coupling, and clarity cap CMR for any bypassing.
For the electrolytics, the Nichion Muse is also good like the AudioNote Kaisie.

And way cheaper.

Do you think you will be able to mount the Jupiter's in such a way to not have to extend the case? Can't wait to see pictures of this. Also, how did you extend your case and where did you acquire the materials?
Thank you for all your input here!

 

[Maxx134]

To extend case was a bit tricky as the board needs to be buffered or it will get the weight .
I used screw extenders from tube guards.
I will take pics when I open for upgrade.

 

[baronbeehive]

To extend case was a bit tricky as the board needs to be buffered or it will get the weight .
I used screw extenders from tube guards.
I will take pics when I open for upgrade.

I used screws and brackets from a meccano set, ideal size for the purpose, unfortunately my own boyhood set had long gone and so I had to buy new ones!

Do you think you will be able to mount the Jupiter's in such a way to not have to extend the case?

The Jupiters will fit, and the cathode caps, the problem is the bypass caps, I don't think you will be able to get these to fit without extending the base, you could look at different caps measurements to see.

It's not my system, let's make that perfectly clear!

Ha... no I didn't mean to suggest that it belonged to you... heaven forbid, just that you had access to such a system!!We can all dream but I return to the review of my amp which suggested that nobody with an expensive system would contemplate using such a cheap component - the APPJ - with extreme high end speakers because of the differential in price but that was the only reason, not the quality of sound of the APPJ.

I came across the speaker APPJ, called the Miniwatt, because I had a SS amp at the time with a tube preamp and wanted to replicate the sound I got from this setup with a bit less complicated system. The Miniwatt did this…. and more! And part of the fun was that it was cheap, and overlooked by others!

My APPJ is a headphone amp, not a speaker amp, and the only thing I could do would be to hook it up to the Esoteric stack (transport, DAC, Rubidium Clock) and see how it performs there...I'm almost afraid to do that...it might melt my mind...

I think I see your problem, I would be scared to even switch on this system!

Edit: Your blackgate caps should go some way to achieving the SQ you want. I wondered if you could maybe do an exchange with some of these highly desired caps for a pair of Jupiters perhaps, if you have some to spare.

 

[Rick_B]

I used screws and brackets from a meccano set, ideal size for the purpose, unfortunately my own boyhood set had long gone and so I had to buy new ones!



The Jupiters will fit, and the cathode caps, the problem is the bypass caps, I don't think you will be able to get these to fit without extending the base, you could look at different caps measurements to see.



Ha... no I didn't mean to suggest that it belonged to you... heaven forbid, just that you had access to such a system!!We can all dream but I return to the review of my amp which suggested that nobody with an expensive system would contemplate using such a cheap component - the APPJ - with extreme high end speakers because of the differential in price but that was the only reason, not the quality of sound of the APPJ.

I came across the speaker APPJ, called the Miniwatt, because I had a SS amp at the time with a tube preamp and wanted to replicate the sound I got from this setup with a bit less complicated system. The Miniwatt did this…. and more! And part of the fun was that it was cheap, and overlooked by others!

I would like to try something like that on the system, but the room is medium sized and damped, the few watts out of a single 6V6 type tube just wouldn't be enough to push the Spendor D-7s to a reasonable volume....maybe the Reference 3As he has, but the CAT amps, or the Pass XA250's are a better fit...we've tried a set of Dared 845 based SET amps, and they do sound sweet on the Ref 3As, but that's what 20? 25 WPC? A bit more than the 6V6...now, maybe in my Ham Radio room system with the Loth-X Ion BS-1 speakers, or the Loth-X Amazes and the smaller volume and closer listening perspective of the room it would sing...but that is where I do most all of my headphone listening in the night when the significant other has trundled off to bed, and boy, do I not like to wake her up when she has retired for the night!

I think I see your problem, I would be scared to even switch on this system!

We have a system that is sitting at 250K retail at work, so I guess I'm a lot luckier than a lot of people in what I get to listen to....

Edit: Your blackgate caps should go some way to achieving the SQ you want. I wondered if you could maybe do an exchange with some of these highly desired caps for a pair of Jupiters perhaps, if you have some to spare.

Well, yeah, I'd be willing to do an exchange, the Black Gates I have are 330uf@25V F types, if there is any interest LMK....

 

[baronbeehive]

I would like to try something like that on the system, but the room is medium sized and damped, the few watts out of a single 6V6 type tube just wouldn't be enough to push the Spendor D-7s to a reasonable volume....maybe the Reference 3As he has, but the CAT amps, or the Pass XA250's are a better fit...we've tried a set of Dared 845 based SET amps, and they do sound sweet on the Ref 3As, but that's what 20? 25 WPC? A bit more than the 6V6...now, maybe in my Ham Radio room system with the Loth-X Ion BS-1 speakers, or the Loth-X Amazes and the smaller volume and closer listening perspective of the room it would sing...but that is where I do most all of my headphone listening in the night when the significant other has trundled off to bed, and boy, do I not like to wake her up when she has retired for the night!

Yes, indeed!

All I can say about this, bearing in mind I'm an interloper on this thread with my APPJ, different to the title of the thread - but they do have things in common, is this: I can't usually go more than half volume without deafening myself, and my speakers are only 87db so shouldn't really work.... but it does work in a big way!

Have a look at this review: http://www.6moons.com/audioreviews/miniwatt/miniwatt.html

This is an earlier model than mine.

 

[Rick_B]

Yes, indeed!

All I can say about this, bearing in mind I'm an interloper on this thread with my APPJ, different to the title of the thread - but they do have things in common, is this: I can't usually go more than half volume without deafening myself, and my speakers are only 87db so shouldn't really work.... but it does work in a big way!

Have a look at this review: http://www.6moons.com/audioreviews/miniwatt/miniwatt.html

This is an earlier model than mine.

I have actually seen and heard one of the Miniwatt amps several years back in a customers house...used for a desktop system...

I have a pair of 3.5 watt Bottlehead Paramours that I built years ago so I do know how far a few watts could punch, especially on the Lowther DX55 drivers in my Third Rethms, or even on my Klipsch Hereseys...

 

[Haidar]

I'm considering some changes to the circuit. If one were to remove all the negative feedback, what would the output impedance be?