Me and My new F6

[Bare]

Finally got it together and it Works ! yippee.
Initially tried on disposable 'tester' speakers, a pair of Mark Audio Diy efforts that never met expectations.
Sounded Good.. far better sound than those had ever made previously.

This AM the Big reveal.. I tried with my (bought New in '72) Tannoy Golds.
Initial/instant impression was: Yikes!
Instant 'M..e..l..l..o..w ' was the immediate impression. a palpable sounds 'reduction'. Dissapointment being the immediate reaction.
Yes, it pains to say that.

Curiously, with extended listening; detail was certainly still there, bass still had subtle variations but subtle Sharpness and Impact were 'Smooothed' out.. missing actually, recordings seemingly lost their 'edge'
A significant shortcoming IMO.
My fave 'tester' recording: Joe Bonamassa's "Acoustic Evening at the Vienna Opera House", lost much of it's live recording realism.
Even Hand claps aren't quite right imo.
Lesser albums seem to Sound more like a back row seat at a Lounge performance.
Dire Straights (which I admittedly don't much like sounds simply 'mushy' to my ears. Lounge MuZak

My inexpensive Akitika Lm3886 based amp does Soundstage and Realism notably better.. weird and completely unexpected.
Arguably the F6 may have a bit finer detail, not sure either way.. yet.
Hopefully this is early days yet and I have yet to fiddle around with my Pre or fit a 10K passive pot cobble up.

Dunno.. lotsa possibilities. Not giving up by any means.

What does strike as odd cuz it's nowhere else mentioned, is this is a ..Mellow... amp.
Desirable synergy on Harsh speakers that need taming ?
However, on those that Don't (barring further adjustments to my gear), Perhaps not so great /ideal.

Going to have to remove the F6 from my setup, for a few days at least, to reset my ears/brain before I can make another try at evaluating the sounds.

 

[Russellc]

Finally got it together and it Works ! yippee.
Initially tried on disposable 'tester' speakers, a pair of Mark Audio Diy efforts that never met expectations.
Sounded Good.. far better sound than those had ever made previously.

This AM the Big reveal.. I tried with my (bought New in '72) Tannoy Golds.
Initial/instant impression was: Yikes!
Instant 'M..e..l..l..o..w ' was the immediate impression. a palpable sounds 'reduction'. Dissapointment being the immediate reaction.
Yes, it pains to say that.

Curiously, with extended listening; detail was certainly still there, bass still had subtle variations but subtle Sharpness and Impact were 'Smooothed' out.. missing actually, recordings seemingly lost their 'edge'
A significant shortcoming IMO.
My fave 'tester' recording: Joe Bonamassa's "Acoustic Evening at the Vienna Opera House", lost much of it's live recording realism.
Even Hand claps aren't quite right imo.
Lesser albums seem to Sound more like a back row seat at a Lounge performance.
Dire Straights (which I admittedly don't much like sounds simply 'mushy' to my ears. Lounge MuZak

My inexpensive Akitika Lm3886 based amp does Soundstage and Realism notably better.. weird and completely unexpected.
Arguably the F6 may have a bit finer detail, not sure either way.. yet.
Hopefully this is early days yet and I have yet to fiddle around with my Pre or fit a 10K passive pot cobble up.

Dunno.. lotsa possibilities. Not giving up by any means.

What does strike as odd cuz it's nowhere else mentioned, is this is a ..Mellow... amp.
Desirable synergy on Harsh speakers that need taming ?
However, on those that Don't (barring further adjustments to my gear), Perhaps not so great /ideal.

Going to have to remove the F6 from my setup, for a few days at least, to reset my ears/brain before I can make another try at evaluating the sounds.

Odd, I had a very different first impression. So did some others, but those reports were generally with the high end being a bit on the over done side, one member adjusting his speakers crossover to get things right. Mine seemed to slowly mellow out, although I did increase port size to increase "bassiness" and dialed down the compression horn tweet a couple of notches in the beginning. After a while this was no longer necessary.

More in line with your findings, I found initial sound to be quite recessed especially sound stage wise. The stage did not project beyond the front of the speakers and seemed trapped behind that line.

With a little time, the soundstage came more forward and spread out more. It expanded a surprising bit over a little more time, high end mellowed a touch and they were fine. High frequency artifacts were superbly reproduced, with much detail. My M2 did the same thing concerning burn in. At first, distant and murky. shortly, it came into its own and seems better every time I listen.

I would let the amp burn in a while and see what you get. If it doesn't improve, something must be off. It is a truly impressive amplifier. Reading the reviews at "New record Day" and 6moons reveal it to be a winner...it their opinion anyway.

Russellc

 

[2 picoDumbs]

If you like to experiment then you could increase the amount of feedback. That should give the perception of extra detail.
Or if you have the ability to match mosfets that should help too.

Have you measured noise at the output?

 

[Zen Mod]

it's already plenty of facts regarding adjustment of THD spectra of F6

all you need is semi-decent sound card , little reading and adequate software

 

[wdecho]

I am the one that changed my crossovers with the F6 and the change made all my amps sound better. It needed doing. I did not recognize the deficiency of my crossovers until the F6, it is that good and revealing. My soundstage is outstanding with the F6 equal to some of the 4 SET's that I own. Vocals are forward and not laid back. The F6 should sound fantastic with your conventional speakers. I would do some component changing if this is not the case. It should not sound as you have described it.

Reviewers of the Firstwatt built ones have nothing but praise for this amp.

 

[Bare]

Thanks for the thoughts gents. Appreciated.
Spent the last couple of hours with the venerable lm3886 based amp reinserted (f6 'in storage' for the forseeable future).
Instant.. Immediate sounds improvements.
SAME detail level.. I'm Now convinced the F6 has NO detail advantage that I can hear.
Playing Tommy (the Who) was immediately Raucous, Brash and in My room the ..Dynamics... are Front, Centre and Impressive.
Bass is once again palpable in my diaphragm, Kick drums I can physically feel the impact of and the Soundstage is Huge.. get up and walk around big, easy to pick out instruments and follow them through the piece.
Whereas my F6's soundstage is Iffy to small.. period, a Striking difference.
Seriously Kids.. there Are serious differences here.
Frankly reminds me mostly of an Se 45 meshplate contraption that I briefly fooled with 20 yrs ago.
Nice but wayy too Mellow/No dynamics and a bit of PITA to live with.

Honestly the F6 does sound Decent. Just not near to what I expected.
I fully understand how on some speakers it could be a Godsend.
But.. on Mine it's OK, but mostly Mehhh. Not a keeper.

Dunno about the crossovers.
I experimented with the Crossover design that 'papa' claims is on His Tannoys... in '96 and discarded /moved on from it by '97.
There Are better configurations... but then there always are
However Most All Tannoy 'improvement' paths are well trodden, 45+ yrs on
Anything is possible but I Seriously doubt that MY Tannoys' crossover is any problem.

Sooo.. the theory is that I Can Tweak the F6 to 'same as' my other amps' performance levels?
Erm.. WHY would I want to do that?
In real life Teslas can leave Porsches for dead as small example. Modern technology and 1/2 to 1/3rd the price 4 seaters too. Tough to equal let alone beat using yesterdays' Gear.
My cheapish /low pedigree amp Driving MY Tannoys is Wayyy more enjoyable than My F6, it's dynamics are Outstanding and it's detail resolution is seemingly at least Equal.. As Is.
Had I not gone through this exercise I wouldn't have believed it either.
The pedigree does overwhelm one.

Clearly, however there ARE other amplifier technologies.

 

[2 picoDumbs]

Tweaking is fun, but if that is not your cup of tea no problem.
By the sound of it probably a BA2/BA3 with Push Pull output stage or F5 is probably more to your liking. Or the New Sony pt 2 amp.

What was Idss on the jfets. This is important on this amp, as the frequency response is not it's strong point and a decent amount of current is needed because of the transformers.

It is very easy to increase feedback to get some improvement.

 

[vdi_nenna]

It's a matter of preference. You might like your sound to be a bit brighter.

 

[Dennis Hui]

Sorry the F6 didn't work out for you. Building a class A amp is a non-trivial
endeavour so I can appreciate your disappointment.

Good luck with any future projects and happy listening.

Cheers,
Dennis

 

[Bare]

Thanks.
Merely immediate dissapointment /ranting
I'll get over it.
Likely revisit it all in the fall.. prolly experiment with it then
All bits from DIYAudio shop including matched jfets.
Following the recipie seemed important No ad libbing
Tannoys NEED heavy current capable amplifications.
Those big heavy cones do poorly without significant current control. (I've learned a little bit about them since '72 )
Forget that and weak bass /dynamics result.

 

[wdecho]

I've built both the Gainclone LM3875 and Gainclone LM3886 amps. Both are acceptable amps with the edge with my speakers going to the LM3875. Neither one comes close to the F6 using a good tube pre with my speakers in my room and the F6 is not my favorite FW amp. The M2 is better with my speakers to me. IMHO

What exactly are you driving your F6 with? The F6 is much quicker than any amp I have heard with outstanding bass. You are giving up on your build much too quick. Any of the 4 FW amps I have built were better sounding than either gainclones and the gainclones do sound good but harsh and irritating with female vocals. I would have been happy with the LM3875 if I have never heard of Firstwatt.

 

[Russellc]

Interesting, I have found the F6 to be one of the most detailed amplifiers I have ever listened to....and that is over 40 years of listening. The description almost sounds like something is out of phase. It should have a giant soundstage. Do mess with it further.

If you think it just doesn't have enough juice to properly drove your speakers, I heartily recommend a complimentary output BA3 with a 24+24 volt transformer.
All things considered it is basically my favorite Firstwatt type amp....except the M2 within its power limitations...but if F6 isn't getting your speakers going, it is no more powerful.

This said, I would carefully trace all wiring, also mine needed about 100 hrs to really come into its own. If you are located near other members, it might be interesting to play amp-speaker swap to see if that reveals anything.

Normally, this amp is raved about, "New record day" stating that it may be the best amp they ever listened to."

I don't know about all that, but it should have been a pleasing result. I have one system with a set of small 2-way monitors that clipped a 150 watt A/B amp that sounded fine with F6, within reasonable sound levels...it really takes the BA3 to wake them up.

In closing, you should be getting a huge, highly detailed soundstage when this amp is properly working, baffled here, sorry it did not work out.



Russellc

 

[Mobin]

Interesting speakers: TannoyMG15

 

[Zen Mod]

interesting that I'm finding all bigger FW amps (so , around 25W/8R/ch) more than capable to drive big Tanns , no matter what cabinet sort is in question

let's say that I didn't heard yet even slightest amount of power compression even when my kiddoe is watching Harry Potter , while M2 is powering my Absolute WAF OB Tanns , and those being 4-ohmish in lowest region

I'm much more polite listening da muzak

 

[Russellc]

interesting that I'm finding all bigger FW amps (so , around 25W/8R/ch) more than capable to drive big Tanns , no matter what cabinet sort is in question

let's say that I didn't heard yet even slightest amount of power compression even when my kiddoe is watching Harry Potter , while M2 is powering my Absolute WAF OB Tanns , and those being 4-ohmish in lowest region

I'm much more polite listening da muzak

Zenmod, you asked during my build in one of my posts to comment in a few weeks as to my enjoyment of M2. Well, I have to agree it is a magical beast and I am enjoying it immensely!!!

Russellc

 

[Zen Mod]

it's either something wrong with his (OP) F6 , or something is wrong with his Tanns

that ,speaking with some modest experience with various Tanns and same with various FW amps , F6 between them

 

[Russellc]

it's either something wrong with his (OP) F6 , or something is wrong with his Tanns

that ,speaking with some modest experience with various Tanns and same with various FW amps , F6 between them

Agreed. Hopefully he will take it out and play around a little.

Russellc

 

[Soundhappy]

Curiously, with extended listening; detail was certainly still there, bass still had subtle variations but subtle Sharpness and Impact were 'Smooothed' out.. missing actually, recordings seemingly lost their 'edge'
A significant shortcoming IMO.
My fave 'tester' recording: Joe Bonamassa's "Acoustic Evening at the Vienna Opera House", lost much of it's live recording realism.

Personally i like 0,47R and 0,57R source resistors be wire wound Aerton Perry
not inductive version for example Vishay brand or Mills.
It's moderate cost modification and can bring you sound "touch".
Front end adaptation and biger psu caps with more ?00 000 uFarads
Congratulations & best regards

 

[Bare]

Well My Serbian Friend..
I've owned MY Golds since summer of '72.
After Looong audition of pretty well All speakers available in 1971..these proved imo the Best possible choice. Still are imo.
How long have You been fooling with Tannoys?
So Please: Don't insult My intelligence and I won't needs insult yours

IMO there is Zero wrong with the drivers... they work to all my expectations with Most Any amp.. except my F6
Over the years, I've done myriad Box and Crossover experiments.. including the Bespoke Ridely Active crossover.
More minusses than plusses with that gizmo to be honest, so it's currently 'having a rest'.

Currently running Troels 'improved' MG crossover
It's proving quite good actually, being arguably better than anything else I've fitted, 'arguably' being the operative word.
However that's Always a personal/perceptual point.

Dunno IF there is Anything wrong with MY F6.
Could be.. could have bungled 'something'... Hopefully not, as I'm fairly fastidious/careful and Cautious. But bungles are always possible.
Only thing for Sure is that the thing's Current performance is dissapointing.. at best.
My Setup has suffered Many amps over the last 40+ years and experienced less than stellar fittments.. before.
Frankly the most similar experience to My F6 was a bespoke SE 45 meshplate (these were popular in the early 90's).
It was nicely detailed but it lack any genuine presence, featuring Seriously reduced dynamics and farty bass. Not a keeper.
Curiously some still maintain that these are better than Sex on their Tannoys.. to which I can only suggest that they get a Girlfriend.

MY F6 performs strikingly similar, isn't it largely touted as Tube like ??

Possibly !? my issue lies in my Pre, a 'bespoke' tube/triode contraption that has pleased for ~15 years.
Notably other amps have dropped in and out of this same system setup with NO issues whatsoever... again; Dunno.
What I was planning on was Cobbling up a twin Stepped Attenuator 10k each passive gizmo in lieu of a Pre in front of the F6... when I get 'aroundtoit'.

Not tomorrow though.. My Current setup is sounding 'Jes Fine' thanx

 

[Zen Mod]

Well , my Canuck friend - I was contemplating strictly with facts I have , reading your few posts , laying on table what's possible , what is not possible .

One , who is in situation to check all shiny glimpses from my not so shiny crystal ball , is nobody else than you ....... but you certainly didn't comment what I wrote in post #4

what is also important - which pcbs you're using , and are you possibly victim of pcb mess-up with wrong connection of electrolytic caps in output mosfet's gates circuits

further - are you using SS or mosfet outputs , what values of source resistors are there , which input JFets are exactly ........

so , while I'm making mistake here and there , I'm certainly not keen of insulting anyone's intelligence



that's why I'm always insisting on posting pictures, exact schematic , measurements etc.