Tobes Posted May 10, 2017 Posted May 10, 2017 (edited) Item: Location: Central VicPrice: $1400 + shippingItem Condition: Very good (minor marks)Reason for selling: Surplus to requirementsPayment Method: Pickup - Cash, PaypalExtra Info: This amp is a build of the Nelson Pass First Watt F6 design. (Note, after initial Pass build runs Nelson Pass releases his First Watt designs to the DIY community. The Pass built F6 continues to be available at US$3500). Like all Nelson Pass First Watt amps the F6 circuit is a pared back, purist design. Matched FET buffers drive the Jensen transformer which in turn drives a pair of the output MOSFET'S - that's it. As usual the circuit design has been expertly honed by Nelson Pass with extensive listening tests determining the final circuit. While not built by Pass, this is a Nelson Pass F6 amp - carefully put together by a couple of SNA members using premium parts. Parts include the same Jensen signal transformers specified by Pass; Matched FETS/MOSFETS; Charcroft, Caddock, Dale and Mills resistors; Elna Silmic caps etc. This amp is built into an overkill rugged chassis. Power output is 25W/8ohms, 50W/4ohms. A link to the build thread for this amp is here: http://www.diyaudio.com/forums/pass-labs/278695-upgrade-f5-f6.html I bought this amp only a few weeks ago off another SNA member to use with my super low sensitivity HE6 headphones(!) - yeah I know, overkill. While waiting for the amp to arrive I got a deal on a dedicated Bryston headphone amp and no longer require the F6. I've used it with the HE6's and it sounds marvelous - plenty of detail and great tonal quality. The amp is dead quiet and the Pass specified thermistors in the power supply ensure a delayed soft turn on with zero pops on power up/down. Pics below. Note there are some minor scuffs on the chassis - eg scuff on the top right corner of the faceplate highlighted in the bottom pic - otherwise the amp is in very good condition. Pictures: Edited May 11, 2017 by Tobes 1
WorkinClassAudio Posted May 11, 2017 Posted May 11, 2017 Couldn't find the scuff on the faceplate at first. A black texta would fix that.
ghost4man Posted May 11, 2017 Posted May 11, 2017 I believe @andyr was talking about wanting a First Watt.
Full Range Posted May 11, 2017 Posted May 11, 2017 This F6 looks like my old friend - GLWTS No expense was spared as the best components were used in building it 1
Tobes Posted May 11, 2017 Author Posted May 11, 2017 3 hours ago, Full Range said: This F6 looks like my old friend - GLWTS No expense was spared as the best components were used in building it Yes, I believe you know it well. Funny thing. Like I said above I bought this amp to try with my HE6 headphones. I deliberately didn't try it with my Harbeth speakers - partly because I'd tried a 20W class A Xindak amp previously and it was kind of sluggish/bland compared to bigger amps, and partly because I was using balanced pre outs for my speaker setup and didn't want the upheaval of sorting out integration of an SE amp. Since I'd decided to sell I thought I'd give it a play with the Harbeths........sounds really good. So now I'm buggered. I've changed the thread to an EOI instead of FS while I sort through my options. Maybe I'll sell the Halcro.
Full Range Posted May 11, 2017 Posted May 11, 2017 @Tobes With reservation I sold the F6 to fund the building of the M2 The F6 build is specked out to the hilt with the best available components I would suggest that you live with it a while and let it amaze and surprise you
Tobes Posted May 11, 2017 Author Posted May 11, 2017 Sounding wonderful with the Chesky recording I'm playing at the moment - lovely textures and harmonics with acoustic instruments. 1
andyr Posted May 12, 2017 Posted May 12, 2017 16 hours ago, ghost4man said: I believe @andyr was talking about wanting a First Watt. Yes, if the test I am about to do with ZB's ME75 produces a flat REW response to 20Khz - instead of the steep roll-off at 16Khz which I currently get - then I will build an F5 Turbo. (50w into 8 ohms, instead of the F6's 25w.) Andy
Full Range Posted May 12, 2017 Posted May 12, 2017 6 hours ago, andyr said: Yes, if the test I am about to do with ZB's ME75 produces a flat REW response to 20Khz - instead of the steep roll-off at 16Khz which I currently get - then I will build an F5 Turbo. (50w into 8 ohms, instead of the F6's 25w.) Andy Andy See if you can get to try a Holton A class 50w amp If only just to compare
ghost4man Posted May 12, 2017 Posted May 12, 2017 36 minutes ago, Full Range said: Andy See if you can get to try a Holton A class 50w amp If only just to compare @Full Range It will struggle mate into 2 ohm load. The only modules that I know that are unconditionally stable into that low impedance is the 800 and 1200 series modules. I'm going to the build the 800's. Anthony is currently making those modules for me as we speak. 1
Full Range Posted May 12, 2017 Posted May 12, 2017 6 minutes ago, ghost4man said: @Full Range It will struggle mate into 2 ohm load. The only modules that I know that are unconditionally stable into that low impedance is the 800 and 1200 series modules. I'm going to the build the 800's. Anthony is currently making those modules for me as we speak. Yes I remember posting on your thread But let's not take up to much banter on this EOI thread 1
Full Range Posted May 13, 2017 Posted May 13, 2017 24 minutes ago, hyper said: Under the hood? Sent from my SM-G955F using Tapatalk I will help out with this request 1
hotJ Posted May 13, 2017 Posted May 13, 2017 (edited) These are some exotic parts porn! Did you soldered yourself or just assemble the boards? Edited May 13, 2017 by hotJ
Full Range Posted May 13, 2017 Posted May 13, 2017 (edited) 17 hours ago, hotJ said: These are some exotic parts porn! Did you soldered yourself or just assemble the boards? They were soldered member @Green Wagon His profession is electronics and he also makes wicked crossovers Have a look at how the Jensen transformers were soldered - specifically the wicking effect All components also have a 1.5 mm gap height from the boards Edited May 13, 2017 by Full Range 1
djb Posted May 13, 2017 Posted May 13, 2017 Amps built by fanatics with no $$$ limitations are great buys used I'd express interest except it won't drive Magnepan ribbons at 2 ohm
Tobes Posted May 13, 2017 Author Posted May 13, 2017 I've decided to keep this amp and I'm going to rearrange my system around it. Sometimes its strange how things work out. 2
Full Range Posted May 13, 2017 Posted May 13, 2017 29 minutes ago, Tobes said: I've decided to keep this amp and I'm going to rearrange my system around it. Sometimes its strange how things work out. Good decision Enjoy the fruits of my labour a little
Recommended Posts