a glorious tube, and such an easy amp to build (except for gridstoppers needing to be as close to the pins as you can...these things oscillate given the chance) Salas HV shunt supply, edcor TX (cheap as chips), 4.7uf caps on outputs. Simple design and Salas has done the hard work with the...

Looking through so many valve amp threads there are so many that are OTL (output tranformerless). Do we think its just economics? Good 470uf low esr electrolytics are about £7 each. Reasonable performing transfomers can be had for £20, really good transformers are ~£100 each. I have three amps...

I havent built anything in ages... but lockdown and a sports injury pulled me back to my old box of valves. D3a parafeed, cascode dn2540, edcor transformers. Just waiting on the power tx and its good to go. CCS will be @ 19ma, currently using leds to bias, but may try SIC diodes. I may also...

Hi all.   Thought i would post this here.   There has been some discussion on diyaudio about the sonic merits of a mosfet gyrator Vs a CCS anode load for triodes (or in this case a triode wired pentode - the D3a)   I have already built a CCS loaded d3a amp so now i am building a...

Hi,   I am building a parafeed headphone amp... and am going all out on this one. Its a two chassis build   Does anyone have a recommendation for umbillical connectors (B+1, B+2, Heater, heater, big fat ground)   Also, the chap i am building for has an array of headphones so the...

Hi all,   I am going to build an amp for a mate shortly. He has a big(ish) budget and wants a valve based head amp to power his HD650's and possibly hd800s down the line.   Thoughts so far   Amp Section 6h30p CCS active load, dn2450 cascode LED bias Sowter 8665 50% mu metal...

mods please remove if not appropriate, but i think UK'ers will like this. april 1st only (and its not a joke).

inspired by some of the various mods being done to a close relative of the noodle dac I decided to go down the tranformer route. I bought a pair of sowter (uk tranformers) for £7.99 off ebay (they are normally £54 each) and replaced the entire output stage of the dac with two...

i am doing a Front panel express for a hifi2000 galaxy m, 330 * 230 *80. Does anyone know the panel hole dimensions (i get a rectangle through the centre of the holes measuring 319*65.35) Also, is there a standard countersunk hole that fits the stock allen key screws ( i measure "hole for...

Hi, I am trying to source a three pin connector, the pins are spaced around 2.5mm (probably 0.1") but the typical molex connectors dont quite fit. They have small raised 'arrows' to lock in the female block. Cant seem to find them online at all. Any ideas? Cheers

Hi, I just built a very simple supply for some input switching boards. paralelled secondaries of a 9-0-9-0 transformer. Bridge rectified. 1000uf cap to ground. measures about 13vdc. however, when i measure the ac voltage on ouput.... my meter says 34VAC. tried another meter, same...

I want to make a simple preamp, so a common cathode triode should fit the bill. In the parts bag i have: 210v tranformer (With 6.3 tap). 6n6p's, good signal caps. Ez81, a 40uf, 220uf caps. Question is what operating point shall i run at? reading around its suggested to go hot with...

Hi all, Having built this http://img254.imageshack.us/img254/7696/huey2wf7.jpg I now need to build a preamp with source selector and volume. I dont need any additional gain. Trying to do this on a budget so i am thinking about canabilizing my Soha + jisbos. Here is my plan...

I am considering adding a valve output stage to my dac (voltage out). this circuit looks fairly simple.... what have people here tried?

It seems many people seem to love the board stuffing and wiring, but hate the casework - or even never case things up. Lets start a thread with key tips Drawing software: something simple like ms visio lets you accurately draw the case and components to precise dimensions. Didgital...

Cavalli Audio Bijou: A Streamlined Futterman Design First, thanks to Runeight of these forums for such a fantastic design and his unbelievable support to the DIY community. Hats off. Also, thanks to Jeff Rossel for supplying the boards and components, he is fantastic to deal with and a...

my headphone history is pretty simple. in chronological order alessandro ms1, equation rp-21, beyerdynamic 990 pro, hd 650 My current amp compliment beresford dac (and headphone amp built in), millet starving student, soha, soha + expensive tube + jisbos buffer. the alessandros sounded...

Hello, I spotted an internal pic of a darkvoice 336 on another forum. The output caps are three 10ufd film caps. 30uf seems low for anything but 300ohm phones. 32 ohm phones e.g. grados will have a cutoff of 165hz, this seems very high. Surely, if these are genuine output caps (by...

I wanted to build a cheap dac for my father to use between his airport express and hifi. I bought this from ebay for £30 delivered: Spdif / toslink in, Digital / Analog converters: CS4397 24bit 192khz DAC Digital receiver : Crystal CS8416 currently house in a cardboard box (but is...

hi, Now my soha + jisbos is all done and cased up i have got round to a lot of listening. Cracking mids, detail i didnt know existed. however, i am missing really low bass, the sort of none musical bass if that makes sense - e.g Faithless: bring my my family back there is a low rumbling...

I am putting together a soha with jisbos and e12. This is going in a galaxy m 230*230 case from hifi2000. Can you check this layout and make any suggestions. I will be using silver 4n wire for signal carrying.

All, I recently purchased some opa627's (bp) that didnt work as specified. I contacted Texas Instruments who have since confirmed they are counterfiet. I am waiting from a reply from the supplier before i release details, but its somewhere that has been suggested here as a good cheap...

Hi, I want to try some different opamps in my Dac. I have a few opamps in dip format (socketable) but the dac has soic pads. Anyone know where i can get a converter? Cheers

I have just put some bp 627 opamps in my Soha amp. The detail has certainly been boosted, airy highs...but the bass has lost impact over the opa2134. They have barely had an hour on them, should i be expecting them to grow in the bass department?

Hi, I have a littledot 2+ amp, it has russian power tubes so doesnt arc ever. However, there is a quiet white noise in the left channel, music soon drowns it out, but does anyone have any ideas what this could be? it is not attenuated by the pot. It goes if i plug out my source. Any RCA...