Bottlehead Mainline Headphone Amp

Armaegis · « **Reply #20 on:** 3 Feb 2018, 09:48 pm »

Quote from: adydula on 2 Feb 2018, 03:52 am

Thanks David...

I would think the HP1 with those specs would be unmerciful period....I really respect what Tom has done with this amp. I have a strong inclination to build one. But the others are tempting as well....and at this price point I would like to just get it and plug it in and go....still have a few months before the budget will allow so will keep reading and contemplating....

I'll throw another vote in for the Neurochrome. Absolutely fantastic amp. I wrote up a review for it; I don't remember if I posted it here or over at head-fi.

DavidS · « **Reply #21 on:** 4 Feb 2018, 01:53 am »

seems like different headphones might match up well with different amps. What would be nice match in Mainline. Owning the Neurochrome have been thinking about what would be ultimate match - have read Tom used Senn 650's with the amp (which definately didn't work with my MAD amp). The other amp that has intrigued me is Torpedo 3 - nearly purchased a few times but understand a 4 might be in progress.

adydula · « **Reply #22 on:** 4 Feb 2018, 06:02 am »

Names? Each to his/her own....and you arent forced to look or buy. So many choices out there....lots of them.

Been running thru my amps this past week and most are good, some are great with what I have for headphones...some continue to
surprise me....the Bottlehead Crack with speedball absloutley blew me away today....its so dang good with T1's.

Makes the Mainline very interesting, most crack owners that have built the mainline state its another great step forward....hmmm.

The Woo Audio WA6SE is a built ready to fly amp that many folks drool over and like....

All these are still in the running here...but I have this soldering iron and havent used it in awhile!!

:>)
Alex

megabigeye · « **Reply #23 on:** 6 Feb 2018, 02:21 pm »

Just to stoke the flame a little, looks like the Mainline is on sale today through Sunday! At $250 off, it now costs less than a grand!

adydula · « **Reply #24 on:** 6 Feb 2018, 07:58 pm »

No stroking necesary...saw that...the tie is now broken...on order!!!

LOL

Alex....stay "tuned" or is that "tubed"....

borism · « **Reply #25 on:** 6 Feb 2018, 11:44 pm »

Good decision!

I've built a few BH kits myself including Stereomour, Eros and Crack/Speedball. For me no purchase of a completed component has rivaled the great feeling of putting something together myself and performing the resistance, voltage and listening tests at the end.

jk@home · « **Reply #26 on:** 7 Feb 2018, 12:47 am »

I built a Bottlehead S.E.X. amp years ago, still have it. I really wish they would offer a tube buffer kit, like a stripped down BeePre 300B. I bet it would sale well.

adydula · « **Reply #27 on:** 7 Feb 2018, 08:31 pm »

I am listening to my Crack w/speedball at the moment, just got a new set of replacement pads from Beyer....they were a little difficult to get streched on ...but
we prevailed!! LOL.

Its amazing how well the T90's and higher impedance cans sound with this simple OTL amp.

I guees I could be happy with this one amp, but then that would be no fun!! Ha!

The soundstage with the crack is by far the best I have heard with these cans for sure....very three dimensional and very muscial....great to get lost in the
listening part and not think about your equipment.

I have the schematics for the Mainline now and its a very simple amp as well..will be interesting to compare to the Crack at hand.

Thinking about the build and what to paint the xfmr bell housing and if I will paint the top mounting plate. Also wondering about the wood base.
Stain, linseed oil, varnish etc..

The $250 off sale goes until this Sunday I think, and it sure helped in making the decision!!

Alex

adydula · « **Reply #28 on:** 13 Mar 2018, 10:39 pm »

Mainline has been shipped will be here next Tuesday!!

Will post pix of the build!

:>)
Alex

adydula · « **Reply #29 on:** 22 Mar 2018, 02:57 pm »

Well we are off to a good start...

All mechanical parts mounted...

All electrical boards populated and soldered sans one 49.9 ohm resistor.

Two coats of tung oil on the wood base..

borism · « **Reply #30 on:** 22 Mar 2018, 03:00 pm »

Looks good!

adydula · « **Reply #31 on:** 22 Mar 2018, 09:35 pm »

First power supply check, passed ok, 6.3VAC and 390 VDC...Started wiring the inputs to the input selection switch and the transformer safety ground stuff.

Will take a couple of days to do all the wiring....cutting the wires to length and stripping teflon coated wire is a real pain!

May not be able to get this done due to the missing resistors...

Alex

adydula · « **Reply #32 on:** 25 Mar 2018, 12:42 pm »

Stepped Attenuator...

adydula · « **Reply #33 on:** 25 Mar 2018, 12:45 pm »

Most wiring done, (4) pc boards to be mounted and wired next...

adydula · « **Reply #34 on:** 25 Mar 2018, 02:34 pm »

All done except for two 49.9 ohm resistors that were missing in the kit...have to wait until Tuesday before
the power on testing...

dpump · « **Reply #35 on:** 26 Mar 2018, 10:14 pm »

(done in my best Jedi voice): This is not the amp you are looking for. You will send the amp to me when it is completed.

Seriously, that is a beautiful build job. Can I be first in line to purchase it if you decide you want to sell it?

adydula · « **Reply #36 on:** 26 Mar 2018, 10:34 pm »

Ha!

Thanks for the nice comments!

If I ever sell it I will PM you first!!

Hoping to get the missing resistors tomorrow and be able to power it up for the first time!

Will do comparisons to my BH Crack w/speedball and my Schitt Vahalla2 and my several other DIY amps.

Alex

adydula · « **Reply #37 on:** 27 Mar 2018, 09:17 pm »

Ok the I just installed the resistors from Bottlehead, 49.9 ohms and did the voltage checks...all looks great. Biased the two 6C45Pi tubes to 145 Volts and plugged in
my Schitt Bimby MB and pressed "play"...

"MUSIC!"

This is a great feeling to have a fairly complex project work first time!

Been listening for an hour now and its a very good amp...all the switches and attenuation settings seem to work ok, quiet no noise.

Had a little high freq squeel with first turn on, that went away as the amp warmed up and has not come back. Most likely the
new tubes coming to life!

Sound is really nice, my T1's have not worked so well!! On the high impedance settings there is more than enough EMF to make you loose your
hearing!!

Wonderful wide soundstage, very musical, not this syrupy sound people state when talking about tube amps..very clean, no hiss etc..

One really nice thing is the two inputs that are switch selectable...I hooked up two pc's with two different dacs and level matched them and synched
the same song on both and with a flip of a switch I can instantaneously listen to one or the other and see if there are any differences..

So now I know the difference between and ODAC and a Schitt Bimby....first hand!!

I didnt think the stepped attenuator would be to my analog liking but it has more than enough articulation.....dont feel like I need to be
in between the steps..

BH sent a set of Russian 6C45pi's and a Conn 12AU7A. Not much tube swapping here due to the signal tubes used and the 12AU7A is the power supply tube, not in the
signal path..so tube rollers need not apply here!

Just listen to great music...

Alex

restrav · « **Reply #38 on:** 28 Mar 2018, 12:58 am »

Great work. Enjoy

adydula · « **Reply #39 on:** 28 Mar 2018, 12:59 pm »

Thanks!

Its always a neat thing to have stuff work well, especially the first time....I was looking for the easy way out, plug and play and came close to buying the Woo Audio WA6SE, but as luck would have it they had a sale on this amp at BH and it was reduced $250. Being retired and on a budget it meant a lot to me and my liking to build stuff and learning in the process made the decision easier for me.

There isnt a lot of stuff written up about this amp, but growing up back in tech college in the 60's we learned tube theory and just started to understand Germanium transistors and PNP and NPN !! LOL. Drawing load lines for tubes in circuits for linearity etc...so the nostalgia is definitly here for me.

I watch as folks spend good bucks on all kinds of NOS tubes and the like....thinking and hoping these magic bottles of my era will lead them to audio nirvana!!...LOL.

With this amp, the 6C45PI tube is not well known, and their are only a very few substitues which makes even the desire to play with tubes, well out of the question pretty much.

The folks at BH are really nice, informative and will answer your tech questions and assist in troubleshooting if needed.

I have a pair of Salk SongTowers and a Van Alstine Ultravalve amp for 2 ch listening, and still like this very much, but to play in that area the cost rises quickly...so the head amp
area is much more affordable to get a good setup going..Many comparitively low dollar amps and dacs to choose from.

This is the most I have spent on an amp for cans ever...

Now that I have this and experience what it is like I could now just buy this one amp and be very happy...but how do we know this unless you try different stuff!!??

Oh well the journey has been great so far!!

Back to listening and thinking about the next "build"~~

Alex