which amp to build?? should it be a hoso??? or recommend me a better one!

[jase128]

Hi All,

Im going to build an amp, I love the idea of the hoso's but which one?      or should i build something else? 

needs to have ability to play quiet so a vvr or ppimv is a must, clean and crunchy!

Im no designer so it needs to have bom and layouts with schem's please..........  and as im in the u.k.  would someone advise  where to get transformers and which one I will need  please as livinginthepast has now closed down and ampmaker is quite limited.

all time in replying is much appreciated

many thanks

Jason

[jase128]

For the hoso do I just use vox ac30 transformers?

 will these do.........?
http://modulusamplification.com/AC30Rocket-Output-Replacement-Transformer-MOD0012-P5460517.aspx#
http://modulusamplification.com/AC30Rocket-Output-Replacement-Transformer-MOD0012-P5460517.aspx



thanks


Jason

[PRR]

> I love the idea of the hoso's

hoso ? ? ?

Home-office/small-office? Head on skin off? High Oleic Sunflower Oil?

There is an audio cable company but that is Hosa.

> ampmaker is quite limited.

Ah.... do you mean NoSo One no-soldering amp kit? Never saw that. Sadly out of stock.

[jase128]

> I love the idea of the hoso's

hoso ? ? ?     maybe one of these......  http://el34world.com/Forum/index.php?topic=20017.0
or these http://el34world.com/Forum/index.php?topic=17863.0
or this..........http://el34world.com/Forum/index.php?topic=15863.0
but probably this....http://el34world.com/Forum/index.php?topic=5901.0

Home-office/small-office? Head on skin off? High Oleic Sunflower Oil? =omega-9

There is an audio cable company but that is Hosa.  nah, I said hoso

> ampmaker is quite limited.    a LTD company!

Ah.... do you mean NoSo One no-soldering amp kit? Never saw that. Sadly out of stock.   no they have 4 left in stock but a bit pricey for me!!!

yes sorry I should have said HoSo56 guitar amplifier.

thanks for your input


Jason

[John]

http://el34world.com/Forum/index.php?topic=6176.0


Hi Jase, that thread will give you a day's worth of reading.

[Willabe]

> I love the idea of the hoso's

hoso ? ? ?

Geezer (and Tubenit?) amp. It's in the schematic section section.

[jase128]

Thanks John - I will read through it today!

Willabe - yes I have seen them but there are about 8 different versions and I dont know which to go with or has something better come along since as the Hoso amp looks like it arrived here in 2009!!  thank you for your post though!

many thanks

Jason

[tubenit]

Geezer's HoSo56 is one of the most touch sensitive amps I have ever built or played!  GREAT amp!

If you like EL84's & amps with EL84's,  I would build the original that Geezer did.  Obviously, EL84's are one of the most popular power tubes out there and there are 1000's of current production amps with those in them.

Having said that,  I am not a fan of EL84's so I experimented with other power tubes and found the design adaptable to just about any power tube I tried.  I am not a big fan of Vox or Matchless amps with EL84's as they seem sort of chimey to me.  But I admit they sound good in a band.

When I was playing with a band,  I used 6BM8's in one and mic'd the amp into the PA system.  It worked quite well and when I had the chance to hear others play my amp in the band context, I thought the amp set well within the mix.

IF you primarily play at home,  I think the 6BM8 is a reasonable choice at a 7-9 watt volume. 

Doing it over again,  I probably would not build one with reverb and instead use a simple passive effects loop with a delay pedal.

You could use a tube rectifier and a PT that has 275-0-275.  With a 5Y3GT, you'd have about 300v on the power tubes.  With a 5V4, you'd have about 325v.  With a GZ34,  you'd have about 350v.

With respect, Tubenit

[jase128]

TUBENIT  you are a star

much appreciate the time to respond and thanks for a great post.

6bm8 sounds right as i mainly play at home, do I need to worry about current if swapping out rectifiers if the voltages are varying from 300v - 350v?

I shall start my bom and crack on........

Jason

[tubenit]

I would try to build this with having 300v - 315v on the plates of the 6BM8 tubes.

I have build 6BM8 amps using the triodes of the triode/pentode 6BM8.  And I have built amps using just the pentode section of the tube and a 12A_7 variety as the LTPI.   Both ways have been fine for me.

I would consider a PT with 250-0-250  to the 275-0-275 type range with 120ma or more.  You can use an old stock 5Y3GT or a 5V4 tube rectifier to get your voltages where you want depending on the PT you choose.

The HoSo56 that Geezer designed is one of my favorite amps ever!  Very sweet touch sensitive amp to play.  I've used both a 10" Ragin Cajun and a 12"  Cannabis Rex  with one and both sounded good to me.

With respect,  Tubenit

[shooter]

Only from a well fertiled mind can you get;

High Oleic Sunflower Oil

[jase128]

I would try to build this with having 300v - 315v on the plates of the 6BM8 tubes.

I have build 6BM8 amps using the triodes of the triode/pentode 6BM8.  And I have built amps using just the pentode section of the tube and a 12A_7 variety as the LTPI.   Both ways have been fine for me.

I would consider a PT with 250-0-250  to the 275-0-275 type range with 120ma or more.  You can use an old stock 5Y3GT or a 5V4 tube rectifier to get your voltages where you want depending on the PT you choose.

The HoSo56 that Geezer designed is one of my favorite amps ever!  Very sweet touch sensitive amp to play.  I've used both a 10" Ragin Cajun and a 12"  Cannabis Rex  with one and both sounded good to me.

With respect,  Tubenit

great info again, I will order a couple of rectifiers and have a test
Speaker would have been one of my next questions!!  your one step ahead Tubenit!

what choke spec. would you consider?

massive thanks again Tubenit

Jason

[tubenit]

Hoffman's small choke is a great buy and is suitable for Deluxe or Deluxe Reverbs.   I'd use that.

with respect, Tubenit

[jase128]

Hoffman's small choke is a great buy and is suitable for Deluxe or Deluxe Reverbs.   I'd use that.

with respect, Tubenit

Im in the U.K. so the shipping will be massive, Im sure i would be better off buying local.
but thanks yet again

Jason

[PRR]

> Only from a well fertiled mind can you get; Quote     High Oleic Sunflower Oil

I actually blanked on the HoSo around here (sorry!). That list came from some internet site. Heads On Skin On was new to me. (It is a way to sell _shrimp_; but looking-up the whole phrase gives other results.)

[jase128]

No Problem PRR

only some of us are perfect 

would we happen to have a layout for the 6bm8  HoSo pretty please?

Jason

[tubenit]

Are you still planning to build the 6BM8 HoSo56?    IF so,  I will try to draw up a layout to match this schematic for you this weekend.

Here is a version with PPIMV  (post phase invertor master volume) that would be useful for playing at home quietly.

Question:   Are you planning on using the 6BM8  triodes for the LTPI?   It is fine to do so.  It sounds great and will save you a tube.

The advantage of not using those and using a 12A_7 tube is that you could use a 12AT7 in the LTPI to increase headroom for a cleaner tone if you wanted.  OR a 12AX7 for more gain.  You simply leave the triodes unhooked with the 6BM8 tubes.  Remember that 6BM8's are still being produced.
Another advantage is if you ever decided to use a different power tube like a EL84, then it would be easier to swap out since you already would have a 12A_7 wired up as the LTPI.

IF you are serious about proceeding with this,  I will draw you up a layout for it.

With respect, Tubenit 

[jase128]

Are you still planning to build the 6BM8 HoSo56?    IF so,  I will try to draw up a layout to match this schematic for you this weekend.
yes I am 100%

Here is a version with PPIMV  (post phase invertor master volume) that would be useful for playing at home quietly.

PPIMV is a must for me playing at home!

Question:   Are you planning on using the 6BM8  triodes for the LTPI?   It is fine to do so.  It sounds great and will save you a tube.

The advantage of not using those and using a 12A_7 tube is that you could use a 12AT7 in the LTPI to increase headroom for a cleaner tone if you wanted.  OR a 12AX7 for more gain.  You simply leave the triodes unhooked with the 6BM8 tubes.  Remember that 6BM8's are still being produced.
Another advantage is if you ever decided to use a different power tube like a EL84, then it would be easier to swap out since you already would have a 12A_7 wired up as the LTPI.
My preference would be to try the 6BM8's, like you said in an earlier post about el84's being chimey

IF you are serious about proceeding with this,  I will draw you up a layout for it.You are a superstar  , many thanks
Im 100% building this amp, I started my parts list last night and was in touch with a Tx supplier and were on....

With respect, Tubenit

again Tubenit, many many thanks

Jason

[shooter]

but looking-up the whole phrase gives other results

I was in the midst of building my wife a "rock-star" bathroom in the late 90's, went looking for fancy shower heads
All innocence was lost

[jase128]

I will try to have a layout for you by Sunday afternoon & hopefully by Sat afternoon.

I am understanding your response to mean that you are wanting also to use the triodes of the 6BM8 pentode/triode tube for the LTPI  (phase invertor) instead of a 12A_7 tube.  IF that is not correct, then let me know so I can do the layout accordingly.

With respect, Tubenit

Yes please Tubenit, lets use the triodes of the 6BM8 to free a little space

many thanks

Jason

[BetterOffShred]

 
I'm excited to see what Tubenit comes up with for this build.  I have read most of his other design builds and find them to be pretty fascinating!
-Brett

[jase128]

I'm excited to see what Tubenit comes up with for this build.  I have read most of his other design builds and find them to be pretty fascinating!
-Brett

I cant wait to hear what it sounds like   

[tubenit]

OK,  it is your responsibility to compare the schematic with the layout to make sure it matches.  IF there is a discrepancy, go with the schematic.

It is also your responsibility to look up the 6BM8 data and make note of the pin out for the triode and for the pentode in each tube.

I have added an "enhance cap" around the entrance plate resistor to the LTPI.  This adds smoothness in my experience with NO loss of treble.

I think you will find this an amazing touch sensitive amp that is fantastic for playing at home!   

After you have it done, please check and post voltages.   You want around 140v on the 5879 pentode plate.  You want around 300v or so on the 6BM8 pentode plate.

I attached some editable ExpressSCH files where you can make edits to the design of the schematic and/or layout.

IF you make a BOM  (bill of materials), please consider sharing it for others.

I would recommend metal film resistors.  Please consider reading this thread on caps to determine what kind of caps you want to use.
http://el34world.com/Forum/index.php?topic=19534.0

If you have limited cap choices, I would suggest Orange Drop caps in the preamp and in the tone stack.  I would suggest Mallory's after the tone stack, in the LTPI and post LTPI coupling caps.   There are lots of other good choices.

And PLEASE post pictures of the final build and some tone reviews or better yet  sound clips. 

With respect, Tubenit

[jase128]

 

wow that was super quick work there Tubenit

many thanks for your time, I will print them out now and tick off/compare schem to layout.

I will prep a bom and share it

and start the board tonight!

do all pots need to be 1/2watt?

thanks again

Jason

[tubenit]

I noticed the schematic I provided had a 5V4 as the rectifier tube but indicating around 300v on 6BM8 plates.  It would be the 5Y3GT that would give around 300v on the plates.   The 5V4 would put on closer to 325v.

Here is a data sheet for the 6BM8:   http://tdsl.duncanamps.com/show.php?des=6BM8

I will say that I have found that the 6BM8 tubes are very smooth when overdriven and have a nice bass response to them.

I typically use Hoffman's Alpha pots.  I believe his are .5 watt pots?

Sent you a personal message with an offer to hear a sound clip of the HoSo56 I had with 6BM8's.  I added a little delay and compression in the mix but used NO effects pedals in the recording.  I think it does a decent job of showing the smoothness of the 6BM8 tone and what a decent bass tone it has for a low watt tube.

with respect, Tubenit

[jase128]

Hi Tubenit,

The P.T. I can get here is 290v - 0 - 290v @ 120mA (B+), what V would be on the plates using a 5y3gt???   could i use a resistor to lower or do I need to source a different  P.T.?

I will have a listen now to the sound clip !!!

many thanks

Jason

[tubenit]

The 5Y3GT is 1.1 X  VAC.    So if you have 300vac with a 5Y3GT, then you'd have 330v.

5V4 and 5U4GT are  1.2 x

GZ34  is 1.3 X

solid state rectification is 1.4 X

These are just reasonable guesstimate approximations but have been very useful to me in amp design and building. 

So  290 X 1.1  would be around 319 v on the pentode 6BM8 plates which I think would probably be fine to use? You might want to make the 6BM8 pentode screen resistor 2.2k/2w instead of 1k to lower the screen voltage a tiny bit.  The 2.2k also will give a little bit more compression to the tone.

Be sure to use an older 5Y3GT, because the newer Sovtek 5Y3GT gives much higher voltage then the 1.1 X  factor.

With respect, Tubenit

[jase128]

brilliant, thanks Tubenit

some handy details to make note of there!

I will now do a search for older 5y3gt's

thanks


Jason

[jase128]

Hi,

I have just finished my week of nights at work and have real trouble turning back round to a normal routine... but I have managed to order the transformers and handmade a chassis for the build.

 Im just in the midst of the parts list/bom and ordering them at the same time.

hopefully tomorrow I will start the turret board (probably a bad idea before i get the parts but I want to get a head start!)  im gonna try it out of ptfe/nylon board to see if it works ok???? worth a try as we stock it at work!!

more to follow................

Jason

[jase128]

Hi again,

could I possibly use a resistor instead of a choke until I can source one??  Its the only item im struggling with now!!

if its ok what size should I use? do I need to change anything else to go with it?

many thanks in advance

Jason

[jase128]

all parts ordered.........................
transformers are here..................

[tubenit]

Sure you can use a resistor instead of a choke.  Try a 1k/3w resistor there.   Look forward to seeing pictures of your build.

With respect, Tubenit

[jase128]

how much difference to the sound (if any) will it make??? not using a choke that is!

I have a choke ordered but the delivery time is quite long!

Jason

[tubenit]

Sometimes a choke can make an amp sound a little smoother. Sometimes just different sounding.  I have 2 amps that I love that I alternate playing thru.  the one I play the most does not have a choke.


with respect, Tubenit

[jase128]

thats interesting, I shall try with both!!!   to see the difference!

Jason

[Ed_Chambley]

Sometimes a choke can make an amp sound a little smoother. Sometimes just different sounding.  I have 2 amps that I love that I alternate playing thru.  the one I play the most does not have a choke.


with respect, Tubenit

I have a 5G9 build with a resistor and choke on a switch.  This circuit it makes a big difference.  At lower volumes I use the resistor as it gets a little dirty sounding at lower volumes.  The choke and dimed volume is sings with a much smoother tone.

[jase128]

Sometimes a choke can make an amp sound a little smoother. Sometimes just different sounding.  I have 2 amps that I love that I alternate playing thru.  the one I play the most does not have a choke.


with respect, Tubenit

I have a 5G9 build with a resistor and choke on a switch.  This circuit it makes a big difference.  At lower volumes I use the resistor as it gets a little dirty sounding at lower volumes.  The choke and dimed volume is sings with a much smoother tone.

splendid idea Ed, if it makes a big difference I will do the same!!!! thanks


Tubenit, i finally got round to read some of the link you posted about capacitors,    ooooohhhhh   mmmyyyy   all these years I never knew it mattered which way round and I didnt think there would be any sound difference in brands (only in tolerences)   

[tubenit]

Tubenit, i finally got round to read some of the link you posted about capacitors,    ooooohhhhh   mmmyyyy   all these years I never knew it mattered which way round and I didnt think there would be any sound difference in brands (only in tolerences

Please keep in mind that there are many different ways of approaching this and ending up with a great sounding amp.  And that personal preferences are just that.  I am sure you can find something that works well for you.

With respect, Tubenit

[jase128]

Ok a little update,

all parts arrived....
I built a (probably too light weight) chassis to save a few £££$$$$   but also because im building this amp to fit in a specific place and its a bit smaller than a standard chassis width. Ive made it 14" x 7" X 1 1/2"   the height is a mistake and the next one will be 2"+  due to not having the room for pots correct orientation!!!!  live and learn   luckily its free

I had a read on placement of trannys, tubes etc etc  and I probably have made a mess of it but again live and learn.... I will finish it and if its not great im  going to mod/change it until im happy!

Im using a 5y3gt but bought a 450v 47uF cap, I dont have the spec on the tube so im going to try and get away with it for now but it might get changed later!

Im working the weekend again but will try and get a bit more done - anything obviously wrong please shout up!!

hopefully photos of "so far.."  attached

Thanks for all help so far

Jason

[tubenit]

What tube are you using for V2 that is octal?

All the tubes except rectifier should be 9 pin IF you are following the original schematic and layout.

You should have two 12A_7 types and two 6BM8 tubes and a 5Y3GT.

With respect, Tubenit

[jase128]

v2 is an ecc83 which for some reason I thought was an 8pin?????

I have spares bases!!!!

Jason

[tubenit]

You can just put a small piece of sheet metal over the larger hole and punch it for a 9 pin socket and replace that with a 9 pin socket.  Easy fix for it. Looking forward to how this build comes together for you and a tone review.

With respect, Tubenit

[jase128]

You can just put a small piece of sheet metal over the larger hole and punch it for a 9 pin socket and replace that with a 9 pin socket.  Easy fix for it.

Great Idea, I will cut some out tomorrow.

Well spotted and thanks for the tip

Jason

{edit- un-tangled quote -PRR}

[super&plexi]

Just a backup to crap sovtek rect's.  Bought different rectifiers when I had some bread...put away for builds, whatever...sovtek flashed second it started . circuit ran fine w/old , & jj rects.    Oh yeah, hated 47uf in tweed deluxe. Have 100+100 in Kbias....getting ready to change that out also to lower.


Take or leave.......but sincere high hopes for your build, & totally looking forward to hearing it!      Can you play like Holdsworth? Jk!  sNp.

[jase128]

"Just a backup to crap sovtek rect's.  Bought different rectifiers when I had some bread...put away for builds, whatever...sovtek flashed second it started . circuit ran fine w/old , & jj rects.    Oh yeah, hated 47uf in tweed deluxe. Have 100+100 in Kbias....getting ready to change that out also to lower."

I bought a  "5Y3GT-HALTRON (Haltron  rectifier" how good they are I dont know????

First cap  at the moment I have a 47uF soldered in but i was thinking of swapping the first two caps around so it hits the 22uF first and then the 47uF (ie 22-47-22-16-10) but I did order another 22uF  so I could just go 22-22-22-16-10 ???   does it matter?

Thanks for the best wishes, I might get my son to do the sound clips because im as bad playing as i am building lol

Jason
{edit-- fixed missing /quote  --PRR}

[jase128]

 

Finally finished the amp,well...I finished it a few few days ago but it didnt work 100% so I have been tracing the circuit with a print out and a coloured pen.
I found a dry joint and a capacitor in the wrong orientation!  just  tried it again and it sounds fantastic 

when I get home from work tomorrow I will try it cranked to see how it really sounds!!  and start planning on a cab!

Tubenit i will get the voltages written up  (what position do you need the pots in??)   take some photos  and there are a couple of corrections to the layout needed and I will put my updated bom together. I will ask my lad to record some sound clips too! many many thanks for the help

Thanks all for tips etc

Jason
 

[purpletele]

Finally finished the amp,well...I finished it a few few days ago but it didnt work 100% so I have been tracing the circuit with a print out and a coloured pen.
I found a dry joint and a capacitor in the wrong orientation!  just  tried it again and it sounds fantastic 

when I get home from work tomorrow I will try it cranked to see how it really sounds!!  and start planning on a cab!

Tubenit i will get the voltages written up  (what position do you need the pots in??)   take some photos  and there are a couple of corrections to the layout needed and I will put my updated bom together. I will ask my lad to record some sound clips too! many many thanks for the help

Thanks all for tips etc

Jason

Jason,

Any updates on your amp and the minor tweaks that you did.

I am considering building that amp and I wanted to see if there was any recent rhetoric.

BV

[jase128]

Hi,

I have not got the amp 100%. I have been through it several times and cannot find anything obvious, I need to get some help from here as its beyond me, I have a feeling its too high a voltage but I need to takes some notes and photos and post !!!

you can get the amp to sound great but there are issues

hopefully later today I will repost ....... stuck at work on nights at the moment!

Jase