anyone modified a Parts Express HTA200

[gentlejax]

I had one but I sent it back but not because it sounded bad but because a different integrated came up and I bought it. now it was 3x as much and has 3x as much power than the HTA200 (100 x 2) but the HTA had pleasant sound and held its own in powering my JBL 590's .

I liked it enough that I thought I will buy it again and throw in some other tubes in it if I dont go ahead and buy a Wilsenton R8 in the future.

anyone taken the time to open up one of these HTA200's to see if its too cheesy to mess with mods & upgrades ? I am not a tech or anything but I figured it wouldnt be too complicated . I dont have one but its cheap enough I have it on my short list of buy agains ...lol...

 

[Doodski]

to see if its too cheesy to mess with mods & upgrades ? I am not a tech or anything but I figured it wouldnt be too complicated

Anything electronic is very sophisticated and can be very complex working on it. The Dayton Audio HTA200 is no different.

 

[JSmith]

Unless it's for fun/hobby, just buy a normal solid state amp and forget about tube rolling/"upgrades".


JSmith

 

[gentlejax]

Anything electronic is very sophisticated and can be very complex working on it. The Dayton Audio HTA200 is no different.

ive repaired a few amps before. I was just meaning I am not an engineer trying to modify the design. Im talking caps and simple things most people who can solder might do. done it before.

 

[gentlejax]

Unless it's for fun/hobby, just buy a normal solid state amp and forget about tube rolling/"upgrades".


JSmith

well if it were not for fun then why would anyone do most anything?

ive had more amps than I can remember ..not sure why you thought I needed another. Being this is ASR I thought there might be some others who have used it and thought about improving it since as is its pretty cheap and certainly made with the cheapest parts to keep the cost down.

the response surprises me as I didnt say I was trying to redesign the circuitry or something requiring so much effort that it outweighed the cost or result.

There are people here on this site who make a living selling amps made by hand after they sourced parts that allowed them to do so . they could have just never attempted that either and bought another amp already assembled. I made a few myself with the same parts . for the fun of it.

I guess I should go to DIY audio or some other place for this kind of idea

 

[fpitas]

were not for fun then why would anyone do most anything

You might be surprised how many people come here and ask about DIY speakers in connection with saving money. Have fun though! I agree DIY Audio will be more sympathetic.

 

[gentlejax]

You might be surprised how many people come here and ask about DIY speakers in connection with saving money. Have fun though! I agree DIY Audio will be more sympathetic.

Sometimes its like that. When i asked about doing something simple on my Lexus i was told by the stiffs that i needed to buy a different car . But it came from someone who obviously had no idea what i was talking about. I get it. Not everyone has a tinkering side.

Speaking of speakers , i have parts iid love to make into functioning speakers. Thanks for reminder

 

[mhardy6647]

For something along the lines of the HTA-200, I would not bother.

100 watts x 2. Yah, sure, you betcha.

 

[fpitas]

For something along the lines of the HTA-200, I would not bother.

100 watts x 2. Yah, sure, you betcha.

I *think* it's just an SS output, class AB. So it might do that. The transformers on deck must be the power transformers.

 

[mhardy6647]

I *think* it's just an SS output, class AB. So it might do that. The transformers on deck must be the power transformers.

I thought it was class D and (most likely) 100 wpc into 4 ohms at 1 kHz and at 10 % THD. Could be AB, but even if so, I am pretty sure it's more like 30 wpc in terms of anything like "hifi" performance.
I mean, I guess we could get one drop-shipped to @amirm

I realized when I posted, though, I should offer the OP (@gentlejax) an alternative.
Here's food for thinking*:

Why not build a nice little amplifier consisting of a cathode follower (buffer) input stage using a good triode (or twin triode) tube at its proper operating points, feeding a pair of good quality Class D mono power amp modules? This would use a vacuum tube (one 12AU7 or 12AX7 could suffice for both audio channels) for something worthwhile and would probably result in a good sounding hifi component.

Something like this for the input:
http://www.valvewizard.co.uk/accf.html

Use a SMPS or go linear

EDIT: Not to put too fine a point on it, but amplifiers like the titular Parts Express item and its ilk are junk. They are designed to have tubes -- but not for any good reason. The tubes are, if anything, a disadvantage in an amplifier like this (these).

There are even worse examples -- I have one here, in fact!

I believe PartsExpress (still) sells a variant of this abomination, too.
EDIT: only the aforementioned '200 watt' and a '100 watt' variant:

Home

Dayton Audio HTA100 Integrated Stereo Hybrid Tube Amplifier 100 WattsDayton Audio HTA100 Hybrid Tube AmplifierThe perfect solution to bring the rich sound of a tube amplifier to your home audio setup; the innovative design of the HTA100 combines the best of both worlds – the classic sound of...

www.parts-express.com

Monprice does still sell it (more or less): more "features" at an even lower price - one may draw one's own conclusions.

https://www.monoprice.com/product?p_id=38360

PS I don't think that the PE amp under discussion can be reasonably compared to a Lexus in any way, shape, or form. More like a Yugo. This being said, I am sure that there are folks who resto-mod Yugos. I am not going to google the topic.

_________________
* "Food for thinking" was a phrase used by an long-ago boss of mine; a VP of R&D for whom English wasn't his first language.

 

[mhardy6647]

Re: Tube rolling and the HTA-200:

Like most of these Asian-sourced amplifiers, the tube types are Chinese types that often have no direct Western substitute. Sometimes there are Russian (or, earlier Soviet) substitutes.
Brent Jessee has a good page on possible substitutes for fringe-y tubes like these:

Russian and Chinese Tube Substitutes

Let's start with that 6K4:

TDSL Tube search [6K4]

The 6K4 appears to be a (power) pentode not a triode. t may (???) be wired as a triode in the circuit. It may be wired as anything in the circuit, including merely using the heater element as a resistor. This was known to be the case in some of the progenitor versions of this amplifier:

I actually have to go do something useful for a while... but we'll look into the other tubes anon.

 

[fpitas]

Re: Tube rolling and the HTA-200:

View attachment 324918

Like most of these Asian-sourced amplifiers, the tube types are Chinese types that often have no direct Western substitute. Sometimes there are Russian (or, earlier Soviet) substitutes.
Brent Jessee has a good page on possible substitutes for fringe-y tubes like these:

Russian and Chinese Tube Substitutes

Let's start with that 6K4:

TDSL Tube search [6K4]

The 6K4 appears to be a (power) pentode not a triode. t may (???) be wired as a triode in the circuit. It may be wired as anything in the circuit, including merely using the heater element as a resistor. This was known to be the case in some of the progenitor versions of this amplifier:

View attachment 324921


View attachment 324920



I actually have to go do something useful for a while... but we'll look into the other tubes anon.

You're badly overthinking this. But I am too: the 13P1P pentode with less noise than it's SS equivalent has me head-scratching.

 

[Doodski]

ive repaired a few amps before. I was just meaning I am not an engineer trying to modify the design. Im talking caps and simple things most people who can solder might do. done it before.

Yes, swapping capacitors, rolling OP amps and other easily swapped parts is not rocket science but it is very sophisticated what is occurring at the circuitry level even if you think you are doing basic simple stuff. I'm all for rolling OP amps and swapping caps when discussing newbies getting their feet wet in electronics PCB working and handling parts and a soldering iron because everybody started somewhere before they became more expert at electronics. I started by soldering entire amps, swapping caps and playing with mechanisms. I ended up studying electronics formally and worked as a technician for about 15 years before I went off into industrial stuff.

 

[fpitas]

My experience rolling op-amps is that they seldom have anything valuable in their pockets.

?What?

 

[Doodski]

My experience rolling op-amps is that they seldom have anything valuable in their pockets.

?What?

After a thorough formal study in OP amps I realized that they are application specific and the designer calculated the circuit parameters for the one in use. I think swapping OP amps is a exercise in futility but it is what it is for newbies and that's practice doing electronics stuff and that might lead them to more serious electronic stuff and maybe even a formal study.

 

[fpitas]

After a thorough formal study in OP amps I realized that they are application specific and the designer calculated the circuit parameters for the one in use. I think swapping OP amps is a exercise in futility but it is what it is for newbies and that's practice doing electronics stuff and that might lead them to more serious electronic stuff and maybe even a formal study.

They won't burn down the house, and yeah they might actually learn what they're doing some day. But it gives me the willies since as you allude to, I calculate everything and model the circuit. Just tossing in another op amp gives me heart palpitations.

 

[mhardy6647]

My experience rolling op-amps is that they seldom have anything valuable in their pockets.

?What?

I am rolling on the floor here.

But it gives me the willies since as you allude to, I calculate everything and model the circuit. Just tossing in another op amp gives me heart palpitations.

.... and that's why you're not an audiophile, Grasshopper...

That said -- you should see the things folks do with those hyper-cheap Asian "tube preamps".

FX Audio 6j1 tube preamp - a $31 wonder

I've been spellbound by the tiny FX for several weeks now. If you follow the TPA3116 thread you know I'm not the only one who has fallen for this pint sized beauty. There's so much buzz in the other thread after pairing it with the class d Volt+D I thought it deserved a thread of it's own. The...

audiokarma.org

 

[fpitas]

.... and that's why you're not an audiophile...

That, and my brain still functions.

 

[fpitas]

That said -- you should see the things folks do with those hyper-cheap Asian "tube preamps".

It is amazing they work at all.

 

[gentlejax]

Well. You guys have just about taken the fun out of it.

I dont have one anymore it was just a thought