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Firebottle
02-03-2016, 12:23
I've built a prototype into an old mil spec box whilst I wait for other enclosures to arrive.

http://i601.photobucket.com/albums/tt97/Paramotorpilot/Head%20Amp/P1050311.jpg

Just listening now and performance is excellent. Early days to tell the difference between straight MC input on the KIN preamp or via head amp into MM input, if there is any :scratch:

I shall be making a demonstrator in a small enclosure which will use a PP3 battery, plus a second model in a larger enclosure that will use a PP9 battery with up to 1500 hours endurance.

:D

Jimbo
02-03-2016, 12:30
That looks like a sturdy box Alan:)

Cant wait to hear it!

Arkless Electronics
02-03-2016, 12:32
The battle of the head amps commences....

struth
02-03-2016, 12:50
http://uploads.tapatalk-cdn.com/20160302/7291fd561c990eba3945740d5eb0933c.jpg

Ding, Ding! [emoji2]

Macca
02-03-2016, 18:06
That toggle switch looks like it came off of a Chieftain Tank.

We need more military-grade hi fi in our lives.

Head amp bake-off at the next NEBO?

Firebottle
05-03-2016, 17:01
http://i601.photobucket.com/albums/tt97/Paramotorpilot/Head%20Amp/P1050330.jpg http://i601.photobucket.com/albums/tt97/Paramotorpilot/Head%20Amp/P1050327.jpg

Internal pics tomorrow :)

Bigman80
05-03-2016, 17:26
That looks great. What's a head amp ?

Wakefield Turntables
05-03-2016, 17:26
Can I try this please?

Wakefield Turntables
05-03-2016, 17:28
Its basically an active version of a step up transformer. Next question what's a step up transformer? :)

Bigman80
05-03-2016, 17:32
Its basically an active version of a step up transformer. Next question what's a step up transformer? :)

Lmao. A SUT is a bit of kit which makes MC to MM On the amp ?

Firebottle
05-03-2016, 17:34
Oliver - A head amp is used to raise the low output signal from a moving coil cartridge so that it can then be fed into a standard moving magnet phono preamp.
It's prime requirement is to be low noise as the input can be in the order of 0.2mV, that's 200 millionths of a volt :eek:

It's an alternative to a SUT (Step Up Transformer).

Andrew - I will be sending out two demonstrators so we can certainly arrange that.

Wakefield Turntables
05-03-2016, 17:40
Andrew - I will be sending out two demonstrators so we can certainly arrange that.

That's great news, it will be going up against a well sorted Lentek and will be used with a barage of low output MC's.

Jimbo
05-03-2016, 18:14
Andy I have an early prototype of the Firebottle head amp running at the moment.

If the fully sorted version is even better than this it will be superb!:)

Bigman80
05-03-2016, 18:15
Oliver - A head amp is used to raise the low output signal from a moving coil cartridge so that it can then be fed into a standard moving magnet phono preamp.
It's prime requirement is to be low noise as the input can be in the order of 0.2mV, that's 200 millionths of a volt :eek:

It's an alternative to a SUT (Step Up Transformer).

Andrew - I will be sending out two demonstrators so we can certainly arrange that.

Excellent explanation Alan. I don't have a MC cart as yet so no need to put my name on the test list lol.

I'll be watching with interest though for the future

Jimbo
05-03-2016, 18:21
Excellent explanation Alan. I don't have a MC cart as yet so no need to put my name on the test list lol.

I'll be watching with interest though for the future

Oliver you would be welcome to come and listen to Alans Head Amp round my place when I get it.

I am very local to you.

Bigman80
05-03-2016, 18:27
That's really good if you Jimbo. I'd Defo be available for that !

Thanks [emoji3]

Jimbo
05-03-2016, 18:29
That's really good if you Jimbo. I'd Defo be available for that !

Thanks [emoji3]

Let you know when it's landed.

walpurgis
05-03-2016, 18:42
Next question what's a step up transformer? :)

Yes? :)

Wakefield Turntables
05-03-2016, 18:48
Andy I have an early prototype of the Firebottle head amp running at the moment.

If the fully sorted version is even better than this it will be superb!:)

That sounds great Jim, I seem to be going through a Head Amp phase at the moment, this will be the third I've tried this year.

Jimbo
05-03-2016, 18:54
That sounds great Jim, I seem to be going through a Head Amp phase at the moment, this will be the third I've tried this year.

I am still waiting for a K&K SUT to be reconfigured to 1:10 step up ratio to try with my Denon 301 mk2 but I have a feeling Firebottles Head Amp is going to sound even better.

I will post up my thoughts in the next few weeks!

Bigman80
06-03-2016, 07:59
Let you know when it's landed.

[emoji3][emoji3][emoji3][emoji3][emoji3]

Marco
06-03-2016, 10:07
Good stuff, Alan. We need more head amps in our lives! :eyebrows:

I'm sure it'll sound fab. As you heard at mine, with the Paul Hynes, a well-designed head amp always seems to bring a little bit something special to the table, over simply what a standalone MC stage does, although I've found that applies mostly with a valve MM phono stage in the equation.


Head amp bake-off at the next NEBO?

Sounds good. I'll bring the Paul Hynes, along with my (currently) very lightly-modded Lentek :)

Marco.

P.S As mad as it seems, experiment with different brands of batteries, as I've found that they all sound subtly different. For me, Duracell is the best!

Ali Tait
06-03-2016, 10:10
Yeah good idea, I'll bring the Denon also.

struth
06-03-2016, 10:12
I like Ever Ready:eyebrows:

Marco
06-03-2016, 10:14
Yeah good idea, I'll bring the Denon also.

Nice one, mate. That sounded superb at the last NEBO, so it'll be a tough act to beat!

Marco.

julesd68
06-03-2016, 13:36
Hi Alan,

Just wondering if you have compared your head amp with the Lentek?

Sorry if I have missed it, but do you have a price set?

Cheers

Firebottle
06-03-2016, 14:38
As promised:

http://i601.photobucket.com/albums/tt97/Paramotorpilot/Head%20Amp/P1050331.jpg

All hand assembled. PP3 battery with 200+ hours, gain 23.5dB (x15), input impedance 100 ohms, quality output caps.

Jules, sorry I've never had a Lentek so no comparison. Price TBA.

:)

struth
06-03-2016, 14:54
Looks good Alan

Firebottle
06-03-2016, 14:58
I like Ever Ready:eyebrows:

Just for you Grant :eyebrows:

struth
06-03-2016, 15:00
:mex::rfl:

Jimbo
06-03-2016, 16:57
As promised:

http://i601.photobucket.com/albums/tt97/Paramotorpilot/Head%20Amp/P1050331.jpg

All hand assembled. PP3 battery with 200+ hours, gain 23.5dB (x15), input impedance 100 ohms, quality output caps.

Jules, sorry I've never had a Lentek so no comparison. Price TBA.

:)

Wow Alan, you said you had simplified the circuit to use as few components as possible but this looks totally minimal!:)

Can't wait to hear it! :cool:

Firebottle
06-03-2016, 18:25
Yes it is a KISS design, I do find them the best usually.
Because of the scale of the photograph you can't really see all the components on the pcb, plus they are all surface mount size anyway :doh:

:D

Wakefield Turntables
06-03-2016, 20:15
really really looking forward to try this and plotting it against my modded Lentek Headamp.

Jimbo
14-03-2016, 12:58
I have just received the Firebottle Head Amp .

Full review later this week!:)

Jimbo
16-03-2016, 13:15
I have now had a number of hours with Alans Firebottle Head amp and I can say it certainly lives up to expectations. Alan has always raised the bar high with his products and the Head Amp is no exception.

Build quality is minimalist perfection. Although Alan has told me a new box is on the way I am sure it will be up to the very solid well engineered standard of the one I used. As you can see from the photos, internal components are minimal which accounts for Alans philosophy of keeping things simple with as few components in the signal path as possible. Less pollution from electrical components the better.

Very easy to install and even the battery is nicely secured and simple to fit. Just one switch and a blue light to let you know its on and free from any trace of hum that I could detect. However it did accentuate a bit of tube rush through my MM phono stage, not a problem as it was not within the audio levels that I would use.

Connected to my system Croft 25R via MM stage and using the Denon 301, it immediately portrayed a wide and deep soundstage. The gain level which I think is 15db was perfect for my cartridge and let me use the volume controls on the Croft at precisely the same settings I would normal use.

As my system warmed up more and more detailed was resolved. I have never heard a sound stage as big through my system but this may have been the head amp allowing the 301 to do its stuff. I played a great jazz record made by Count Basie in a small 5 piece group Kansas City 5 which has a vibraphone player amongst the artists. This instrument popped out of the recording with great immediacy and power with all the texture and ambience of the struck notes. Basie's piano work although slightly less focused had great weight, presence and texture. I know this recording well and it told me a lot of what this head amp could do.

I have heard Alans phono stages and the KIN a number of times and those of you who have heard these will know Alans signature open clear large soundstage. The Head amp almost allows you to achieve this same presentation.

Dynamically it is very good indeed but where it truly excelled was with vocals and midrange. Listening to Convergance ( Boris Blank and Malia) was absolutely excellent, The tonal texture and information in her voice was mesmerising and the same was true with Norah Jones on her album Come away with me. Personally I could not wish for anything better than to hear how these vocals came across.

As the night went on and the noise floor dropped I noticed how well all the micro detail was resolved with very good treble detail and information. Bass is tuneful and tight. Ok I know a lot comes down to the cartridge but for me it was how well the head amp allowed this information to come across through the Croft amp.

This Head amp is certainly something I would recommend anyone to try. An excellent piece of kit that does the job very well indeed.

Superb stuff Alan.:cool:

Firebottle
18-03-2016, 21:13
Due to a monumental screw up by ParcelFarce the 2nd demonstrator is up for grabs to anyone that would like to try it.

Roll up...............:)

Ali Tait
18-03-2016, 22:00
G'wan then, I'll try again.. :-)

vinyljunky
20-03-2016, 15:39
Just gotten a Thorens td160 super with mission 774 tone arm and a Zyx r100 yatra cart so I'm up for trying this too please Alan :please::please::please:

Firebottle
20-03-2016, 16:46
I'll get a demonstrator out to you soon Steven, just waiting for some parts. :)

vinyljunky
20-03-2016, 19:07
Cheers al this one shouldn't get nicked I've moved happy days looking forward to trying it out does it match the gain of a particular cart:scratch:

Gazjam
20-03-2016, 23:36
G'wan then, I'll try again.. :-)


Wouldnt mind a listen Ali when you get it?

Ali Tait
21-03-2016, 05:34
Aye, if we get time.

Firebottle
23-03-2016, 10:39
The first demonstrator head amp is available to anyone that wants to try it.

The second is on it's way to Ali :)

mikeyb
23-03-2016, 11:39
The first demonstrator head amp is available to anyone that wants to try it.

The second is on it's way to Ali :)

I'm bored, I'll try it ;)

Pm on it's way with address.

Firebottle
27-03-2016, 13:19
OK, so I thought I'd compare different output capacitors on the new MC head amp, so I threw together a rough test jig:

http://i601.photobucket.com/albums/tt97/Paramotorpilot/P1050354.jpg

2 'standard' polypropylene capacitors plus 2 'audiophile' tin foil polypropylene capacitors per channel, with a tiny 4 way switch to select between.

Running into the MM input of my KIN preamp, through my AIR power amp and onto the ESL57s.

Very difficult to tell any difference, I'm wondering if the signal level being so low, a few mV from the head amp, will show up any difference.

It may well be expectation bias but I think there may be a greater depth with the audiophile caps switched in :scratch:

Any perceivable differences are going to be very dependent on ones own systems level of ultimate resolution.

:cool:

Ali Tait
27-03-2016, 14:01
Mudorf Zn would be interesting to try.

lurcher
27-03-2016, 14:58
You are making a couple of assumptions:

1. The switch is having no effect
2. Having the unused caps wired to the output is having no effect.

Not suggesting I know if either are true, but the fact they may be to a large extent invalidates the null result you are finding.

Firebottle
27-03-2016, 15:40
Mudorf Zn would be interesting to try.

ZN is one of the tin foil PP Ali.

Firebottle
27-03-2016, 15:44
Not suggesting I know if either are true, but the fact they may be to a large extent invalidates the null result you are finding.

Some good points Nick and things I had pondered. I tested the switch beforehand plus the output impedance is low so should be OK.

I was really wondering if such a low signal level might negate any clouding of the signal by the capacitors?

Jimbo
27-03-2016, 15:56
Paper In Oil?:)

lurcher
27-03-2016, 16:01
plus the output impedance is low so should be OK

All caps should sound the same, using the same logic :-)


I was really wondering if such a low signal level might negate any clouding of the signal by the capacitors

Maybe, if I knew why caps didnt sound the same, I might have a theory that would allow us do decide if the above was true.

Not invalidating your finding you understand, its just I have myself tried to track something down, broken it into its parts, tried each part to see where the effect was, found nothing. But the thing you were looking for was still there. Its tricky this audio stuff :-)

anthonyTD
27-03-2016, 16:06
There's always an issue when you design/build something to be added on to unknown bits of kit.
In this instance capacitors, and their affect, where as if you designed the phono-stage as a whole, you could do it without the need for capacitors in the signal path, someone once said; "the best capacitor is no capacitor" and its something that has always stuck with me! :)

Marco
27-03-2016, 16:13
All caps should sound the same, using the same logic :-)

Maybe, if I knew why caps didnt sound the same, I might have a theory that would allow us do decide if the above was true.


And yet some folk stubbornly insist that we can currently measure everything that we can hear, and that audio is a 'done deal': science has 'nailed it', so there's no more to learn. Game over. Yet we don't know why capacitors sound different? :hmm:

;)

Marco.

User211
27-03-2016, 16:21
And yet some folk stubbornly insist that we can measure everything that we can hear, and that audio is a 'done deal': science has 'nailed it', so there's no more to learn. Yet we don't know why capacitors sound different :hmm:

;)

Marco.

Er.. we do know, don't we? They won't measure the same.

Seriously, they won't. At least that's what I reckon. Correct me someone if I am wrong.

sq225917
27-03-2016, 16:22
First, prove they sound different, then investigate the audible mechanism.

Just because the swap from electrolytic to foil might be easily audible in some instances doesn't mean every capacitor swap is similarly so.

I'm decidedly on the fence regarding many capacitor swaps. (Feedback and small signal EQ being the obvious exceptions).

User211
27-03-2016, 16:26
They are made of different materials to different specs and tolerances. They will surely therefore display different measurable characteristics i.e. charge and discharge rates etc.

Marco
27-03-2016, 16:28
Er.. we do know, don't we? They won't measure the same.

Seriously, they won't. At least that's what I reckon. Correct me someone if I am wrong.

Yes, but the measurements may not necessarily explain the *precise nature* of what you're hearing. If Nick's saying that he doesn't know why some capacitors sound different (and plenty others who've heard the same would agree), then I would say it strongly suggests that that area of audio hasn't yet been 'solved'.

Marco.

User211
27-03-2016, 16:33
I know they don't sound the same. Trust me. But then I wouldn't expect them to, for the reasons I have stated.

Correlating measured differences with what you think you hear? Hopeless cause for subtle differences that people will agree on, I reckon.

I reckon it is this simple - there are so many variables involved, even in simple circuits, understanding the precise nature of how a human will perceive the resulting sound is a lost cause.

Marco
27-03-2016, 16:37
First, prove they sound different, then investigate the audible mechanism.


Yes, but you can investigate until the cows come home, and not find any proof, if you don't know *exactly* what you're measuring for, or crucially, HOW to measure it.


Just because the swap from electrolytic to foil might be easily audible in some instances doesn't mean every capacitor swap is similarly so.


Indeed, but if the former is clearly audible, then what exactly is the cause? I'm afraid believing that the subject of audio is already a 'done deal' is nothing more than grossly simplistic thinking, or worse, the rather convenient appeasing of one's prejudices, for the sake of an easy life! ;)

Marco.

anthonyTD
27-03-2016, 16:41
Basically, its because their crap!:eek:
Seriously, I am sure if you ask any of the guys on here who can design, and build' they will agree that they are a necessary evil in many circuits.
There are as has already been said in this thread''[Justin] too many variables for them to be identical.
A...

Firebottle
27-03-2016, 16:43
My 'belief' with the heavier tin foil capacitors such as Mundorf ZN, is that the miniscule vibration within the capacitor wound foil caused by the alternating field within is damped by the extra mass of the foil.

No proof of course.

awkwardbydesign
27-03-2016, 16:43
I recently read an article, probably via diyAudio, about the storage of charge in completely discharged capacitors, with the terminals shorted. The suspicion was that a soft or loose dielectric allowed the plates to move and then stick in that position until the teminals were unshorted. Which would change the capacitance. And why hard dieletric caps, like polystyrene, are prized. I'll try to find the article again.
EDIT; Here it is. http://www.keith-snook.info/capacitor-soakage.html

Firebottle
27-03-2016, 16:45
Paper In Oil?:)

Not yet but I'm on the case :D

Marco
27-03-2016, 16:52
I know they don't sound the same. Trust me. But then I wouldn't expect them to, for the reasons I have stated.


So what else that we *know* doesn't sound the same (like capacitors), and causes an audible difference, but yet which we can't prove? Interconnects, mains leads - equipment racks??

'Done deal', my arse! ;)

Not everything we hear with hi-fi is 'conveniently imagined', used as an excuse by some because we currently don't have the wherewithal to prove it.... The problem is the fear of uncertainty for those of a 'black or white', absolutist mindset. It bothers them immensely when certain things in life can't be neatly pigeonholed into little 'solved boxes'!

Marco.

User211
27-03-2016, 16:59
So what else that we *know* doesn't sound the same (like capacitors), and causes an audible difference, but one which we can't prove? Interconnects, mains leads - equipment racks??

'Done deal', my arse! ;)

Not everything we hear is 'conveniently imagined'....

Marco.

Did you read the rest of it? Who said it was a done deal? All I said was we're not able to correlate measured changes with our perceptions. Hell we can't quantify our perceptions in a meaningful manner any better than verbal spew. Whereas measuring differences in cables, valves etc is a cinch.

Marco
27-03-2016, 17:05
Indeed. I wasn't implying you were saying it was a 'done deal' - I know that's not your opinion, but it is the opinion of some of the more, shall we say, 'misguided objectivists'. Just read the current thread on pfm about "Posh Kettle Leads"! :doh: :rolleyes:

http://www.pinkfishmedia.net/forum/showthread.php?t=185599

Anything that currently can't be measured, or proven, is thus automatically 'imagined'.... FACT! :wanker:

The blinkered closed-mindedness from some, as evidenced on that thead, coupled with scientific wishful thinking, totally nips my sphincter.

Marco.

r100
27-03-2016, 17:12
totally nips my sphincter....


:scratch::D:lol:

there is more going on than I imagined !!

Marco
27-03-2016, 17:14
Whereas measuring differences in cables, valves etc is a cinch.

As far as I'm aware, we can only measure some basic electrical differences between them, but not that which explains the (often) significant change in sound many of us clearly hear when using different ones.

Marco.

anthonyTD
27-03-2016, 17:35
When you first glance at the make up of a capacitor, it is dificult to understand why they sound so diffrent, but then when you actualy examine them, you find similar diffrences to for eg, cables, ie; diffrent metals, diffrent dialectric, or insulating material between the layers etc, in this respect, why should we accept the diffrences these have on a cable, and not a capacitor ? what i am trying to say is; you can take two very diffrent sounding caps, or cables apart, and examine them in the same way, and come to the same conclusion, and that is, there seems to be so little diffrence in their make up to to actualy warrant such a change in sonics, but most of us who have done the listening tests know what we hear, so, again, there is obviously something that can be proven going on, we just need to look further into it than we do at the prersent to understand it!

anthonyTD
27-03-2016, 17:50
Anyway,
Seen as this is Firebottles development thread, i think we should allow it to get back on track, and if there is a further interest in the capacitor subject, maybe someone can start a new thread in Blank canvas.

Marco
27-03-2016, 17:50
what i am trying to say is; you can take two very diffrent sounding caps, or cables apart, and examine them in the same way, and come to the same conclusion, and that is, there seems to be so little diffrence in their make up to to actualy warrant such a change in sonics, but most of us who have done the listening tests know what we hear, so, again, there is obviously something that can be proven going on, we just need to look further into it than we do at the prersent to understand it!

Precisely!

And that's the attitude we should be taking (as it's the ONLY way to learn and make genuine progress), instead of *automatically* dismissing the currently heard, but unproven, as 'imagined'. To do so, does a grave disservice to scientific learning, and also REAL scientists who possess genuinely inquisitive minds.

Yes, of course we're all fallible human beings, easily capable of being fooled - I fully acknowledge and accept that - *but* that's not necessarily the case every time someone reports the possible existence of a phenomenon that can't be neatly explained by the contents of 'Johnny's Book of Physics'!! :nono:

I abhor such reductionism.

Marco.

Marco
27-03-2016, 17:51
Seen as this is Firebottles development thread, i think we should allow it to get back on track, and if there is a further interest in the capacitor subject, maybe someone can start a new thread in Blank canvas.

Yeah, I was just about to say that. Best leave it for another day ;)

Marco.

User211
27-03-2016, 17:52
As far as I'm aware, we can only measure some basic electrical differences between them, but not that which explains the (often) significant change in sound many of us clearly hear when using different ones.

Marco.

And all I am saying is that the measured differences ARE what we can hear.

Even when there appears to be no measurable difference, if you think you can hear one, and your gut tells you you know you can, then you almost certainly need to measure again, with a much more complex input with some kit that is capable of reading the output in an appropriate manner.

For instance, pink noise as an input, for 5 seconds, versus a digital scope sampling for 5 seconds and saving the result. That will have a complex output. Then simply repeat with the other, different, component, using the same pink noise input, and compare the results.

Don't get me wrong I am first and foremost a subjectivist, who believes that if you can't measure the difference you ain't trying hard enough. So really I'd be amazed if I can hear a difference test kit can't pick a difference up somewhere.

And as I said again, correlating measured results is easy between components, but correlating measured results with subjective verbal descriptions is a different matter.

Example - "I heard more bass with that cable". You probably did - but exactly how much more bass? You can't reliably relay that to anyone in any meaningful manner, though you could easily measure the extent of it.

But there will be examples where the tone is just different in a hard to express way, and those tonal changes are due to a myriad of complex electrical interactions that result in sublety different sound. That is where correlating measurements with verbally expressed perceptions becomes nigh on impossible. Especially where each human will hear it differently because their organic test kit (lugholes and neural nets) differs so radically. Hell, even their different educational backgrounds and upbringing etc will lead them to express things rather differently from each other.

Course I could be wrong.:lol:

Objectivists get it wrong, though. A good example is Serge telling me I couldn't measure a difference between valves (in FR terms as I remember it). So I tried and I found significant easily repeatable differences.

Marco
27-03-2016, 18:04
Serge is a completely lost cause! ;)

We are essentially in agreement, Justin. Anyway, I think we've 'drifted' this thread enough, so back to Firebottle head amps :)

Marco.

User211
27-03-2016, 18:10
Yeah I was getting bored explaining myself anyway:);)

anthonyTD
27-03-2016, 18:11
I think what Nick was saying about the switch, and unconnected capacitors possibly not being totally innocent, as far as sonic effect, is a good place to get back to. :)

Firebottle
27-03-2016, 18:12
Hey chaps this has been great. It's a 'development' thread so any discussion along these lines is very welcome.

I think Justin's post #73 is spot on.

:D

lurcher
27-03-2016, 19:27
For instance, pink noise as an input, for 5 seconds, versus a digital scope sampling for 5 seconds and saving the result. That will have a complex output. Then simply repeat with the other, different, component, using the same pink noise input, and compare the results.

Bloody, hell, why didnt I think f that, its obvious... Oh, I know, because it doesnt work.

Sorry if this sounds a bit harsh, but if it was that simple, it would have been done many years ago. Yes, you can put a capacitor on a analyser, and find all the bulk parameters about it,but it doesn't help (once you get past the obviously broken parts) to derive any coherent theory about why things sound like they do. We spend hours and years building up theories, and then someone comes along with an amp and blows the theories out of the water.

Gazjam
27-03-2016, 20:10
"We spend hours and years building up theories, and then someone comes along with an amp and blows the theories out of the water."
This^

...Like discovering the world WASN'T actually flat?

StanleyB
27-03-2016, 20:25
"We spend hours and years building up theories, and then someone comes along with an amp and blows the theories out of the water."
I have been doing things like that for years, and I haven't finished yet :eyebrows:.

User211
27-03-2016, 21:35
Bloody, hell, why didnt I think f that, its obvious... Oh, I know, because it doesnt work.

Sorry if this sounds a bit harsh, but if it was that simple, it would have been done many years ago. Yes, you can put a capacitor on a analyser, and find all the bulk parameters about it,but it doesn't help (once you get past the obviously broken parts) to derive any coherent theory about why things sound like they do. We spend hours and years building up theories, and then someone comes along with an amp and blows the theories out of the water.

Er... did I disagree? I think not.

Jimbo
28-03-2016, 09:30
The paper in oil caps are going to be expensive and large so not sure if they will fit in the box Alan?

banjoman
28-03-2016, 10:59
Alan

Can I put my name down for the head amp demo unit doing the rounds please

Cheers

DEba

awkwardbydesign
28-03-2016, 12:31
The paper in oil caps are going to be expensive and large so not sure if they will fit in the box Alan?

Alan, looking at your photo, are they 1uF caps? I have a bunch of K40Y-9 PIO caps. 0.47uF/200V. I could send you 4 if you don't already have some; they might fit even paralleled. It's the least I could do. ;)
The top pair are already clear heatshrunk, I would do the other pair.

http://i1134.photobucket.com/albums/m604/awkwardbydesign/Mobile%20Uploads/20160328_131843_zpswc6y0krw.jpg

Firebottle
28-03-2016, 12:53
Yes please, I'll pm my address. :D

awkwardbydesign
28-03-2016, 14:08
Would you like a couple of these, too? Or are they too big? Again, I have several. http://www.audioasylum.com/cgi/t.mpl?f=tubediy&m=183112
http://i1134.photobucket.com/albums/m604/awkwardbydesign/Mobile%20Uploads/20160328_145052_zpsjx73cm5g.jpg

Firebottle
28-03-2016, 16:10
I have got a larger case for one build so I would like to try a couple of those as well thanks :thumbsup:

awkwardbydesign
29-03-2016, 11:35
OK, I'll pop them in with the others.

awkwardbydesign
29-03-2016, 19:10
Posted.

Gazjam
04-04-2016, 18:40
Have one of the loaner units here as Gazjam Towers,
will be having a play tommorow.

I'll be comparing it to the built in MC stage in my Firebottle Plus.
Deba (Banjoman) next up, have his address via PM.

Jimbo
05-04-2016, 06:02
Will be interested in your findings Gaz especially with a comparison with the Firebottle MC stage.

mikeyb
10-04-2016, 16:46
I have the gold coloured one on loan, who's due to get it next ?

Firebottle
10-04-2016, 18:54
There are two gold coloured demonstrator units out on loan so this could get complicated.

Just shout up if you want to try one and pm your details to mikeyb :)

mikeyb
10-04-2016, 20:23
There are two gold coloured demonstrator units out on loan so this could get complicated.

Just shout up if you want to try one and pm your details to mikeyb :)
Ah ok, mind you the bloody great gouge I put on it will help tell them apart ;)


Kidding!

I think I need something else as it doesn't give me much more than my built in stage on it's own, which I'm thinking more and more is really good. Since my tweaking to try the Denon 301 Mk2, I've actually gotten my Zu to sound even better, so that's been a bonus.

Although I've not tried it since the tweaks so I'll give it a go this week if I still have it and see if there's more in it.

banjoman
12-04-2016, 15:20
Me please!
MikeyB - sent PM

mikeyb
12-04-2016, 18:25
Me please!
MikeyB - sent PM
Replied :)

banjoman
25-04-2016, 20:10
Link

http://theartofsound.net/forum/showthread.php?44595-Head-amp-showdown&p=752040#post752040

Jimbo
29-04-2016, 20:11
Just an update on the Firebottle Head amp.

I have now purchased the Firebottle 2000 Head amp and it is some way better than the demonstrator going round at the moment. Not sure if this is to do with the bigger battery or foo capacitors I have in mine. I am sure if you speak to Akan he will tweek caps according to taste or budget. I have PIO in mine which gives the Head amp a more organic less tranny sound.

It is throws a big dynamic soundstage and sounds very smooth indeed with my Denon 301 mk2. Loads of detail and texture. Dare I say this is now giving my K&K SUT a bit more competition and in some areas beats it!

I had my Head amp gain reduced to 26db which suits my cartridge and now works very nicely with the Croft 25R+ .
Loading is 1000 ohms but I will play with 300 ohm loading plugs later. Sounds great and getting better as it runs in a bit.

There is no edge to the sound at all, just full rich lush analogue sound with plenty of balls!

This is a definite recommendation if your in the market for a head amp as it is very well built and does a magnificent job with maximum SPPV.

Jonboy
29-04-2016, 20:15
This is a definite recommendation if your in the market for a head amp as it is very well built and does a magnificent job with maximum SPPV.


Ill second that , had my Firebottle plus a few weeks now and settling in just fine

Gazjam
28-05-2016, 10:28
Had the Firebottle headamp in my system for while now, thought it time to post my impressions and send it on. :)
Thanks to Alan for the chance to try it for myself.
I run my deck into one of Alan's Firebottle Plus phonostages, mines has the MC stage fitted so was looking forward to comparing my MC cartridge playing through that vs Alans headamp from the MM stage of my Firebottle Plus.
My FB Plus has a valve output stage...so would feeding my cart through a different output (and battery powered at that) make any difference?

All hooked up and ready to go, I put on "The Lion's Roar" by First Aid Kit, an LP where the vocals are quite "hot" in the treble and can sound harsh if the system's not right.
First impressions was that the Headamp had more gain than my FB Plus, music seemed louder and it was bit more dynamic.
Happily, the vocals were spot on, it was easy to seperate the two seperate harmonies with no hint of spit or edginess. Quite natural sounding too...as good as my FB Plus MC output I'd say, just louder.
Over the course of the evening I tried a few other albums I know well, swapping between the headamp and my Firebottle Plus' own MC output.

Short version?
I think overall in hifi terms the headamp sounds as good as the direct output from the Plus, but it presents music in a different way.
Music seemed a touch more brightly lit with the Headamp perhaps, which having got used to the way valves do their thing always sticks out for me.
Slightly energetic at the top end, to these ears and preferences sure, but very open and (most importantly) no grain or edge to the sound.
Bass is good too, goes deep is tight and carries the tune along nicely.

Could happily live with either but have to say though that in my system, to my ears I prefer the direct feed from the Plus.
Nothing in it general hifi terms wise (which is quite a thing given the price difference between the headamp and my FB Plus) but its a different presentation from what my ears have settled on I guess.
Its an extra box too as I already have an MC stage, but if I didn't...

I cant think of a better sounding way to let you play with MC carts.
This head amps a bloody good 'un.
Subjectively as good as the MC output in my 500 Firebottle Plus and is highly recommended for those wanting to try moving coil carts.

So, who's next on the loan list? :)

Firebottle
28-05-2016, 11:43
Excellent review Gaz, though I feel I need to point out that you do need an MM phono stage to use the head amp with, so comparing directly with my 500 MC/MM phono stage isn't quite accurate in monetary terms.

The head amp on review is the gold single transistor (per channel) unit:

http://i601.photobucket.com/albums/tt97/Paramotorpilot/Head%20Amp/P1050330.jpg

The Firebottle 2000 twin transistor (per channel) unit offers better performance and the ability to change the cartridge loading:

http://i601.photobucket.com/albums/tt97/Paramotorpilot/2000%20MC%20Head%20Amp/P1050350.jpg
Now with [Firebottle 2000] name badge as gold unit.

~~~~~~~~~~~~~~~~~

The phrases 'and my Firebottle Plus' own MC output' and 'Subjectively as good as the MC output' should read ...own MC input.
Pedant mode OFF.

:)

Gazjam
28-05-2016, 12:15
Ah, can see how it might read like that Alan. :)
Excellent unit and deserves to do well, good job Sir.

The cartridge loading feature will be handy for tuning the sound to your own cart, might have suited my ears more with some loading changes.

Ali Tait
28-05-2016, 14:51
Alan, is there a demo unit with the variable loading available?

Firebottle
28-05-2016, 15:02
Ali, at the moment no, vinyljunkie has a demonstrator with the same board but with fixed loading.

If you want to solder different resistors in it across the input sockets you are very welcome to trial it and do just that.
The default loading fitted to the pcb is 1000 ohms, so accommodate that when working out lower loading.

Send Steve a pm to request the unit.

Ali Tait
28-05-2016, 17:32
Ok thanks.