Seems like I've got some pretty good options here, I'm probably going to start with the PH-16 (board set only) since it seems like the most straightforward to build. I've got alot of spare parts for the chassis so shouldn't come out too expensive.
The ones I'd be interested to try afterwards is SY's design, Borbley 5842 (since I've got a nice matched pair of Ericsson 417A and Amperex gold pin 5842), and lastly Steve Bench RIAA 5.
I'll report back in a few years 😂
The ones I'd be interested to try afterwards is SY's design, Borbley 5842 (since I've got a nice matched pair of Ericsson 417A and Amperex gold pin 5842), and lastly Steve Bench RIAA 5.
I'll report back in a few years 😂
HI guys,
Advice pls is the RJM Phono stage suitable for a Denon DL-301 MC cartridge ?
Im a noob with vinyl playback but am looking into helping a friend build a tube
phono stage to replace his SS unit.
Many thanks
Advice pls is the RJM Phono stage suitable for a Denon DL-301 MC cartridge ?
Im a noob with vinyl playback but am looking into helping a friend build a tube
phono stage to replace his SS unit.
Many thanks
If it's the 6DJ8 based one, then you'll need step-up transformers to run LOMC.
https://phonoclone.com/diy-pho3.html
jeff
Without a pre-preamp or step-up transformer, tubes will be too noisy at 60dB gain.
This one is hybrid fet/tube, up to 63dB gain, and is well reviewed.
https://www.amazon.com/Pro-Ject-Tube-Box-Phono-Preamplifier/dp/B075KPB1P2?
https://www.amazon.com/Pro-Ject-Tube-Box-Phono-Preamplifier/dp/B075KPB1P2?
Many thanks for the suggestion Gents, looks like not as straight forward as I would have thought.
60db gain is huge. If I were to use in input step up trafo, what specs should I be looking for ?
Thks again
60db gain is huge. If I were to use in input step up trafo, what specs should I be looking for ?
Thks again
Following the above discussion , it could be answered with simple ±60dB minus the step-up transformer's gain .
But , it does matter what cart you intend to feed it with and what line stage you intend to feed with it. The more you say the more you'll hear. : )
But , it does matter what cart you intend to feed it with and what line stage you intend to feed with it. The more you say the more you'll hear. : )
@sumotan Regarding Step-up transformers, this page has the best information on the entire web. It‘s not short, but it is understandable and explains very well why the “ideal” math doesn’t work a lot of the time, and how to work within the set of tools you have. A genuinely excellent article.
http://www.rothwellaudioproducts.co.uk/html/mc_step-up_transformers_explai.html
http://www.rothwellaudioproducts.co.uk/html/mc_step-up_transformers_explai.html
Updating this thread, I am almost completing the PH-16, and working towards a Steve Bench RIAA 5.
I'm trying to put my 5842's to use, and have a question about the Borbely 5842 -- https://audioxpress.com/article/borbely-riaa-preamp-with-tubes-project-remembered-and-revisited
Why is the B+ 320V if the 5842 Vp = 100V and 220V is just burned through the 22k resistor?
I'm trying to put my 5842's to use, and have a question about the Borbely 5842 -- https://audioxpress.com/article/borbely-riaa-preamp-with-tubes-project-remembered-and-revisited
Why is the B+ 320V if the 5842 Vp = 100V and 220V is just burned through the 22k resistor?
Take a look at how a common cathode amplifier works.
That 22k resistor is the load on the plate of the 5842.
Is you remove that 22k resistor, the 5842 won't have a load it can work into, and it won't make any voltage amplification.
That 22k ohm resistor does far more than just burn off voltage.
Here's an article about this subject:
http://www.valvewizard.co.uk/gainstage.html
That 22k resistor is the load on the plate of the 5842.
Is you remove that 22k resistor, the 5842 won't have a load it can work into, and it won't make any voltage amplification.
That 22k ohm resistor does far more than just burn off voltage.
Here's an article about this subject:
http://www.valvewizard.co.uk/gainstage.html
One tube can not work alone. We usually have a tube -and- a resistor in a "fight", pulling up -and- down.
#37 posts and not a single word about your analogue source! Nor even a picture.
How many LPs do you have?
Is this venture worth it?
How many LPs do you have?
Is this venture worth it?
Worth it, why not? I’ve always been interested in various phono stage topologies and I learn something new with each project.
I’ve built SS ones — Salas FSP Ultra, Pass Pearl 2 (x2), Millett LRP (x2), RJM Emerald, Bugle 2…
No tube designs yet, hence this thread.
I’ve got a Technics SL-1200G which unfortunately is back at the dealer for a repair and using a Thorens TD-309 in the meantime.
Carts are AT-VM540ml, Goldring 1042, AT OC9-XEN….
I’ll eventually get an ART9XA or HANA ML when one or two wear out.
My collection isnt that large, about 200 LPs but I only buy albums I really like.
I’ve built SS ones — Salas FSP Ultra, Pass Pearl 2 (x2), Millett LRP (x2), RJM Emerald, Bugle 2…
No tube designs yet, hence this thread.
I’ve got a Technics SL-1200G which unfortunately is back at the dealer for a repair and using a Thorens TD-309 in the meantime.
Carts are AT-VM540ml, Goldring 1042, AT OC9-XEN….
I’ll eventually get an ART9XA or HANA ML when one or two wear out.
My collection isnt that large, about 200 LPs but I only buy albums I really like.
Yessss!!! You are my kind of vinylista..
Let's build a valve phono stage.
So many topologies to choose from .....common garden grounded cathode amplifier, grounded grid, cathode follower etc,etc.
Will it be a passive filter riaa ,an active filter,or one that combines both,or a split riaa.
Use a pentode,use a triode,use both...
How about a hybrid of valve and silicon....oh my this hobby will do your head in! I love the smell of rosin as it drifts into my nose.
I say bulid them all and let your ears and test equipment ....be aware that your analogue source will need to fit this straight jacket.
A universal power supply of about 300Vdc in a separate box with at least 2-3 heater dc outputs for low noise.
Use lots of chokes...they sound wonderful.Scour your favourite surplus stores for bargains.Hamfests and over here Radiorallies are great sources for these.
That Baseline Ht of 300Vdc can be then regulated.Which will it be? Series regulated or shunt.
I say try them all.
Oh by the way, be sure to have good stock of wood plank for your breadboard.
Try to keep as many of your projects as possible.....you never know how well one may match up with your future analogue setup.
Let's build a valve phono stage.
So many topologies to choose from .....common garden grounded cathode amplifier, grounded grid, cathode follower etc,etc.
Will it be a passive filter riaa ,an active filter,or one that combines both,or a split riaa.
Use a pentode,use a triode,use both...
How about a hybrid of valve and silicon....oh my this hobby will do your head in! I love the smell of rosin as it drifts into my nose.
I say bulid them all and let your ears and test equipment ....be aware that your analogue source will need to fit this straight jacket.
A universal power supply of about 300Vdc in a separate box with at least 2-3 heater dc outputs for low noise.
Use lots of chokes...they sound wonderful.Scour your favourite surplus stores for bargains.Hamfests and over here Radiorallies are great sources for these.
That Baseline Ht of 300Vdc can be then regulated.Which will it be? Series regulated or shunt.
I say try them all.
Oh by the way, be sure to have good stock of wood plank for your breadboard.
Try to keep as many of your projects as possible.....you never know how well one may match up with your future analogue setup.